Moderators: richierich, ua900, hOMSaR

 
abcgogo
Topic Author
Posts: 29
Joined: Wed Mar 18, 2020 4:57 am

Why do aviation safety agencies overlook obvious safety deficiencies ?

Wed Mar 18, 2020 7:04 am

Hello everyone, I have been a long time lurker but decided to register on airliners.net now. I am not an insider of the aviation industry but am an extremely curious aviation-enthusiast (avgeek). Apologies if I make any mistakes/misunderstandings in any of my post, because I am a noob/average on technical matters. With that said, let me start with the topic at hand.

I have noticed the following shortfalls in aviation safety and wondered why have the various aviation authorities/safety-agencies overlooked them and allowed the manufacturers to get away with them. The list are as follows:--
------------------------------

1) Lack of fuel-dumping systems on small aircraft, especially the business-jets and even on the RJs and narrowbody airliners like A320-family and 737-family. Even the latest long-range large business-jets like Gulfstream's G650ER, G700 and Bombardier's Global-7500 lack this safety feature. Check out this video, where the pilot of a fully loaded Global-6000 tells the ATC that he needs to burn fuel for 5 hours just to reach Maximum-Landing-Weight (MLW).
https://youtu.be/_2YsabrDEug?t=250

Is it possible to land safely with 99% or even 80% fuel load (even if it may lead to requiring lots of intensive maintenance after landing) ? I was under the impression that the maximum safest landing can be done only when the aircraft is just above Maximum-Landing-Weight (MLW), say 20% above MLW....otherwise, it would lead to a crash landing where the landing gear would collapse (unable to handle the weight) and the heavily loaded full tanks in the wings would burst open causing a fireball explosion that could severely-injure/kill everybody on board.....something like the DC-10 crash at Sioux-City.

https://youtu.be/b6JW4NuI5GM?t=2620
------------------------------

2) Why aren't light-jets equipped with thrust reversers or a suitable alternative ? All airliners and the medium size (& above) business jets have it, giving them three ways of slowing down (thrust reversers, wheel brakes, spoilers), whereas the very-light & light-jets are restricted to just two ways of slowing down (wheel brakes, spoilers) which seems to be risky considering the high landing speeds of the jet aircaft. If the brakes fail for any reasons, then only God can save the occupants of the light-jets. Landing on contaminated runways (ice, water, snow, oil, etc.) is risky if we don't have reverse thrust, after all if it was unnecessary the airlines would be the first one to make do without them just to save costs.
------------------------------

3) Why aren't active-feedback joysticks present in aircraft ? Only recently we have seen Gulfstream install "active-sidesticks" which move in-sync with each other giving the pilots feedback of what the other pilot (& autopilot too, if i'm not mistaken) is doing. Even the trainer versions of the Cold-War era fighter aircraft had joysticks which were connected. I understand that fly-by-wire is a different beast, but how am I supposed to accept the argument that companies who could program computers to fly airplanes, could not program the joysticks to move in-sync and give feedback to pilots ? It's shocking that no agency across the world had raised objections to Airbus and other manufacturers offering only ordinary joysticks which is a safety hazard IMHO. Check out these two videos, one of the MiG-23UB instructor's cockpit and of the Gulfstream sidesticks.
https://youtu.be/MRNk6SvrDAk?t=48
https://youtu.be/vXhCJYWvwd0?t=45
------------------------------

4) Why aren't Enhanced-Vision-System, Sythetic-Vision-System or the best of both worlds, Combined-Vision-Systems, made mandatory on all aircraft right from helicopters to propellor-aircraft to large airliners ? Such an important feature (CVS) would greatly benefit safety of aviation. Recently, we saw the news of Kobe-Bryant's unfortunate crash. Maybe crashes like this could have been avoided had the safety agencies enforced mandatory installation of CVS, just like how ADS-B Out has been made mandatory (if i'm not mistaken).
------------------------------

5) Why aren't aircraft equipped with runflat or bulletproof tyres (if that is possible), to ensure that even in case of a puncture the aircraft is still under control and safely comes to a halt rather than skidding off the runway or worse ?
------------------------------

6) Why aren't all airliners equipped with inbuilt airstairs (like on Ryanair-aircraft and ACJ/BBJ) so that they do not have to depend on airport airstairs ? Such a mandatory feature would increase the versatility of airliners usage where in an urgent situation (not emergency), the passengers & crew can quickly embark/disembark instead of damaging the aircraft by using the emergency slides. An example of this is the evacuation of civillians in Yemen done by Air-India (at behest of the Govt-of-India) which sent two A321 aircraft. Luckily for AI, there were stairs available at the war-stricken airport, had it been damaged/destroyed, then there would have been no way for Air-India to be able to board it's aircraft and the civillians would have been left stranded in Yemen. Check out this picture, if they had inbuilt airstairs, then that would have been an additional peace-of-mind factor for them. We have seen many such evacuations where by sheer luck or good planning, there have always been airstairs available, but what if one day the luck/planning runs out and there are no airstairs ? How are civillians going to be evacuated then ?
https://1ep6sa1jro642bl0n01shxzi-wpengi ... EN-FLT.jpg
https://www.airliners.net/photo/Ryanair ... /1277441/L
------------------------------

7) It is a well known safety-measure and/or regulation that cabin lights must be dimmed just-before, during and just-after takeoff-&-landing when the flight is operating in low/no sunlight hours. This is to ensure that in case of any emergency, the passengers & crew can be more aware of their surroundings and their eyes can easily adjust to the dull/dark surroundings which will help them escape instead of being "blinded" (for lack of a better term) by the darkness in case cabin lights are kept bright. Inspite of this being known, I have observed quite a few airlines and business jets operating with cabin lights at 70-100% brightness in low/no sunlight conditions. Why isn't any agency cracking down on such unsafe behaviour ? Check out these videos where you can see this irresponsible behaviour.
https://youtu.be/V3L3mYwgoGI?t=142
https://youtu.be/ejypZ7oSKSg?t=503
------------------------------

8) Why don't aircraft have proximity sensors installed on their outermost parts (such as nosecone, winglets, tails, etc) and on various parts of their fuselage ? These sensors can function similar to parking-sensors in cars (but actively rather than passive) where one of the Multi-Function-Display's (MFD) in the cockpit can show the aircraft diagram and all the sensors readings just like how infotainment systems in cars show the diagram of the car and proximity of objects based on sensor reading. Installing such equipment can ensure incidents like one aircraft's wingtip hitting another aircraft's tail are avoided because the sensors in both planes will start beeping loudly in the cockpit warning the crew of both aircraft of possible collision. All sorts of advanced technology are fitted on aircraft yet something so basic cannot be done ? I am surprised. Check out these luxury cars, they actively monitor their surroundings and starts beeping whenever anything gets too close to the car (even in traffic). Why can't this be done by any aircraft manufacturer ?
https://youtu.be/mERCXWIJFnE?t=97
https://youtu.be/8LY8Rz5aM6A?t=41
------------------------------

9) Why aren't small aircraft mandatorily equipped with autoland and parachutes (like Cirrus, Piper aircraft) when it is well known that pilots of such aircraft tend to be hobbyists rather than full time professional pilots who don't have the vast experience to deal with emergencies or mistakes they might face ? It might increase the costs slightly but it also increases the safety a lot more, thereby reducing crashes. Also, the costs might be reduced due to the "economies-of-scale" factor.
https://youtu.be/gBCUQlF3MMU
https://youtu.be/IcVuubU4BTU
------------------------------

10) Why aren't all airports and aircraft equipped with CAT-3B safety feauture ? Even the famous Gulfstream-G650 does not have it. Isn't it a bit too dangeorous to depend only on EVS/SVS/CVS, instead of the much more safer and more important CAT-3B ? If all airports and aircraft have this feature, a lot of diversions, "Controlled-Flight-Into-Terrain" (CFIT) might be avoided due to pilots being more confident in the aircraft making a safe landing.
------------------------------

11) Why do aviation authorities & safety agencies not take any preventive action, instead only taking reactive action ? Nobody bothered with so many obvious flaws in various aircraft over the years, reacting only when a crash (or two or more) happened. In USA, the FAA wakes up only after something goes wrong, in India the DGCA doesn't care inspite of the numerous engine-failures on Indigo's A320neo (Pratt-&-Whitney engines), and globally nobody raised any of the above 10-points I have mentioned. Why such a lax attitude to safety ? In one of India's languages "Hindi", we have a phrase for this careless/carefree attitude called "Chalta-hai"-attitude. Another term/phrase from Hindi, "Jugaad" (quick fix), is also soemthing I can apply to the aviation agencies of the world who only want to do some face-saving, quick-fix measures after a disaster has happened.
https://www.quora.com/What-is-chalta-hai
http://en.wikipedia.org/wiki/Jugaad
------------------------------

I am sure there are more problems, mistakes, oversights, etc. which I might not know about but industry insider would know. Again, apologies for any mistakes/misunderstandings but please do correct me instead of hating.

Thanks in Advance,
abcgogo
 
benjjk
Posts: 381
Joined: Fri Aug 08, 2014 4:29 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 7:31 am

There's a lot here! The bottom line is that a lot of it comes down to cost. A fact of aviation, and life really, is that there will always be some risk. The risk is currently extremely low, and investing billions and tripling the cost of airfares just to reduce that risk a tiny bit more is not a feasible option.

You might be better off asking some of the questions in the tech/ops forum. But I'll briefly have my say:

1) Your understanding is incorrect. Aircraft are certified to land at their maximum takeoff weight. Landing above the maximum landing weight requires a specific inspection. It has been done many times with not one major structural failure. See the article from Boeing on page 15 of this magazine: https://www.skybrary.aero/bookshelf/books/4370.pdf

2) Reverse thrust is only effective at high speeds. Most of the time they are stowed at 60-80kts. If you hit a wall at that speed you're still in trouble. The solution is redundancy in the wheel braking system to ensure that situation doesn't arise.

3) There has been debate on here about this. Both viewpoints are valid, it's not a black and white issue.

4) That system alone probably costs as much as the whole plane I fly, and is not infallible: https://www.flightsafetyaustralia.com/2 ... ng-things/. It is becoming more and more common though, but you'll find that this encourages pilots to push the boundaries more, and try flying in conditions that they really shouldn't. IFR flight has been safely conducted for decades without these systems so all things considered why make it mandatory instead of just recommended?

5) I do not see how it's possible for a punctured tyre to result in a fatality (Concorde-style situation excluded).

6) Cost, and aircraft are not certified with warzone evacuations in mind. Militaries should be responsible for that.

7) Agencies don't have unlimited resources, and in the big list of safety priorities this isn't that high up there.

8) Sensors are already in the important places, e.g. for tailstrike detection. Otherwise the system relies on pre-flight inspections, ground crews, and passengers going "holy cow the wingtip just hit another plane". Airlines consider more sensors would be an unnecessary cost (and your car doesn't go from -50C to +35C in half an hour, the sensors must be built tough).

9) Increased cost, increased pilot complacency, and costly to certify/prove that it won't accidentally deploy. Becoming more and more common though.

10) Most airports in my country (Australia) never experience conditions requiring CAT3B. The single large-ish airport that might only has it for about 3-4 hours a day, a few days a week, for about 3 months. Some flight delays during these periods are preferred to the cost of installation, maintenance and crew training. The bigger airports worldwide that regularly have these conditions would already have it in place.

11) A pre-requisite of ICAO membership is to take preventative action. The vast majority of an authorities actions are preventative, they just don't make the headlines. Occasionally some things fall through the cracks, but when that happens it is addressed and a recurrence is hopefully prevented.
 
peterinlisbon
Posts: 1742
Joined: Wed Feb 01, 2006 3:37 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 8:13 am

There always has to be a balance between cost and safety. In the end no matter how much money you spend flying is never going to be 100% safe. Accidents will happen, because flying through the air at high speed inherently involves some element of risk. Just like no ship is unsinkable. If every plane cost a billion dollars nobody would be able to fly anywhere and there would be no industry left to regulate.
 
User avatar
Antaras
Posts: 528
Joined: Thu Aug 15, 2019 6:18 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 8:37 am

abcgogo wrote:
1) Lack of fuel-dumping systems on small aircraft, especially the business-jets and even on the RJs and narrowbody airliners like A320-family and 737-family.

Last year I went on a A321neo. Seems like it is dumping fuel. Have a look a this picture (sorry for the bad quality as I was seating on the aisle-seat, alongside with HAN's foggy weather at that moment).
Look, you may see a light-brown liquid flying from the position of the wing:
Image
[sorry, even I can't even see it :(]
About the 737, have a look at this fancy picture of Jetstar Pacific's 737-400

Well I believe that airframe was dumping fuel :roll:
Edit signature
This is a block of text that can be added to posts you make. There is a 255 character limit.
 
KDAL
Posts: 57
Joined: Mon Aug 26, 2019 3:40 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 8:55 am

Antaras wrote:
abcgogo wrote:
1) Lack of fuel-dumping systems on small aircraft, especially the business-jets and even on the RJs and narrowbody airliners like A320-family and 737-family.

Last year I went on a A321neo. Seems like it is dumping fuel. Have a look a this picture (sorry for the bad quality as I was seating on the aisle-seat, alongside with HAN's foggy weather at that moment).
Look, you may see a light-brown liquid flying from the position of the wing:
Image
[sorry, even I can't even see it :(]
About the 737, have a look at this fancy picture of Jetstar Pacific's 737-400

Well I believe that airframe was dumping fuel :roll:

abcgogo is correct. No aircraft in the B737 or A320 family are equipped with fuel dumping capabilities.

If I recall correctly, the reasoning they aren't equipped with it is that it's just not worth the weight or expense on such a small airframe. Plus even at MTOW, they don't need nearly the same runway length to stop that a widebody would.
All opinions and views expressed are my own and not representative of those of Southwest Airlines Co., its subsidiaries, or affiliates.
 
citationjet
Posts: 2544
Joined: Sun Mar 09, 2003 2:26 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 9:06 am

Antaras wrote:
Well I believe that airframe was dumping fuel :roll:


737s cannot dump fuel. You were seeing air vortices coming off the wing.

https://aviation.stackexchange.com/questions/9393/why-doesnt-the-737-have-a-fuel-dump-nozzle
Boeing Flown: 701,702,703;717;720;721,722;731,732,733,734,735,73G,738,739;741,742,743,744,747SP;752,753;762,763;772,773,788.
 
mxaxai
Posts: 1638
Joined: Sat Jun 18, 2016 7:29 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 9:43 am

Antaras wrote:
abcgogo wrote:
1) Lack of fuel-dumping systems on small aircraft, especially the business-jets and even on the RJs and narrowbody airliners like A320-family and 737-family.

Last year I went on a A321neo. Seems like it is dumping fuel. Have a look a this picture (sorry for the bad quality as I was seating on the aisle-seat, alongside with HAN's foggy weather at that moment).
Look, you may see a light-brown liquid flying from the position of the wing:
Well I believe that airframe was dumping fuel :roll:

That's water :smile: If it looks brown that's most likely due to the light conditions.
Wingtips, but also flap edges, elevators and delta wings, create vortices. The air pressure inside these vortices is much lower than the ambient pressure, which leads to a drop in temperature. If the relative humidity is high enough, water vapor will condense. Sometimes the regular pressure drop over the wings is enough to cause condensation.


Fuel dumping is through dedicated outlets; these are usually (but not always) integrated into the flap fairings. Interestingly, fuel looks white as well.
 
User avatar
Ty134A
Posts: 520
Joined: Wed Apr 02, 2008 11:21 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 10:11 am

2) Thrust reversers are not an essential feature, but very common. Imagine a very cold country, with lots of snow and ice and loooong winters. And then imagine that this country is a great aircraft building nation. Surely they would make use of thrust reversers. But then again, check for the reversers on Yak-42. It’s a large airliner and has none, flies in Russia and has no problems with the conditions there. A380 was intended without reversers, but then got 2. Does the Fokker 28MK1000-4000 have reversers? Comets? Tu-104? Do328jet? Seems to be the same with slats. There seems a way around them, if designed so. IL-62 lacks slats, i believe DC-8 as well. Did all 707s and DC8s have reversers?

Hard to get to your conclusions.
flown on: TU3,TU5,T20,IL8,IL6,ILW,IL9,I14,YK4,YK2,AN2,AN4,A26,A28,A38,A40,A81,SU9,L4T,L11,D1C,M11,M80,M87,
AB4,AB6,318,313,342,343,345,346,712,703,722,732,735,741,742,743,74L,744,752,753,763,772,77W,J31,F50,F70,100,ATP,
142,143,AR8,AR1,SF3,S20,D38,MIH...
 
mxaxai
Posts: 1638
Joined: Sat Jun 18, 2016 7:29 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 10:27 am

abcgogo wrote:
1) Is it possible to land safely with 99% or even 80% fuel load (even if it may lead to requiring lots of intensive maintenance after landing?
Yes. The two questions this can be split into are "Can the landing gear carry the weight of an aircraft landing at MTOW?" (it can) and "Is the runway long enough to stop, considering the higher required approach speed?", which depends on the airport. For narrowbodies, most airports have runways that are far longer than what an A320 or 737 needs because these airports are designed around heavy widebodies. Even widebodies can usually return to their departure airport at MTOW but dumping fuel will improve margins against a slightly long landing or reduced grip on the runway surface.

abcgogo wrote:
2) Why aren't light-jets equipped with thrust reversers or a suitable alternative ?
Thrust reversers are heavy. Light jets usually use the same runways as larger jets so spoilers + wheel brakes are sufficient. Light jets also have more leeway at reducing approach speed by using different wing parameters.

abcgogo wrote:
3) Why aren't active-feedback joysticks present in aircraft ?
That's a design choice. Basically, the pilot is forced to look at the instruments to see what the plane is doing. The sidestick or yoke serves purely as a command input. Whether this philosophy is good or not can be discussed but it's not as obvious as you may think.

abcgogo wrote:
5) Why aren't aircraft equipped with runflat or bulletproof tyres (if that is possible), to ensure that even in case of a puncture the aircraft is still under control and safely comes to a halt rather than skidding off the runway or worse ?
Tbh I can't recall a case where that happened. The aircraft's inertia is usually enough to keep it on the runway. Most large aircraft also have two or more tyres per bogey, so a single deflated tyre won't cause much friction anyway.

abcgogo wrote:
7) Why aren't all airliners equipped with inbuilt airstairs (like on Ryanair-aircraft and ACJ/BBJ) so that they do not have to depend on airport airstairs ?
Virtually all airports that are certified for passenger operations have airstairs. The weight of inbuilt airstairs usually isn't justified by the few situations where an airport might not have stairs (unless you're Ryanair). If you really, really need to bring a large number of people to or from a place without airstairs, I'd highly recommend a C-17, A400M or similar.

abcgogo wrote:
8) Why don't aircraft have proximity sensors installed on their outermost parts (such as nosecone, winglets, tails, etc) and on various parts of their fuselage ?
Taxiways should be clear of obstacles anyway. The only situations that can be critical are at a gate or in a hangar, but it's much cheaper to have a wing walker look at stuff.

abcgogo wrote:
9) Why aren't small aircraft mandatorily equipped with autoland and parachutes (like Cirrus, Piper aircraft) when it is well known that pilots of such aircraft tend to be hobbyists rather than full time professional pilots who don't have the vast experience to deal with emergencies or mistakes they might face ?
-----------------------
4) Why aren't Enhanced-Vision-System, Sythetic-Vision-System or the best of both worlds, Combined-Vision-Systems, made mandatory on all aircraft right from helicopters to propellor-aircraft to large airliners ?
When it comes to small aircraft (<20 seats), and especially general and business aviation, acquisition cost becomes very important. Small aircraft and cars are very similar: Some safety features (on cars: airbags, safety belts) are mandatory but many others are optional or only on high-end vehicles (on cars: braking assistants, ESP, fire extinguishers). The owner either "feels" safe enough without them or simply can't afford them.

If I could choose, I'd want the full envelope protection of modern digital FBW systems on each and any aircraft but the cost of those systems is higher than the base cost of a light aircraft.

abcgogo wrote:
10) Why aren't all airports and aircraft equipped with CAT-3B safety feauture ?
ILS systems need to be maintained and calibrated; CAT-3 ILS also requires that no vehicles are within a certain distance from the runway. Pilots further need extra training to do full auto-landings. As such, CAT-3B is not a safety feature but just reduces the likelyhood of a diversion. So it becomes an economic trade-off "how much does CAT-3B cost" vs "how much does a diversion cost, and how many diversions can I expect". You will never have a situation where all airports are stuck in dense fog.

abcgogo wrote:
11) Why do aviation authorities & safety agencies not take any preventive action, instead only taking reactive action ?
Aircraft and engines are very complex systems. Not even the engineering experts, let alone authorities can predict all possible failure modes, and they sometimes even make mistakes or overlook certain things. The certification documents of a passenger aircraft are thousands of pages long. There are also plenty of preventative actions when things are discovered during routine maintenance, for example some 737 were found to have cracks in a certain part and need to be fixed before returning to service.
 
tommy1808
Posts: 12481
Joined: Thu Nov 21, 2013 3:24 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 10:46 am

Ty134A wrote:
2) Thrust reversers are not an essential feature, but very common. Imagine a very cold country, with lots of snow and ice and loooong winters. And then imagine that this country is a great aircraft building nation. Surely they would make use of thrust reversers. But then again, check for the reversers on Yak-42. It’s a large airliner and has none, flies in Russia and has no problems with the conditions there. A380 was intended without reversers, but then got 2. Does the Fokker 28MK1000-4000 have reversers? Comets? Tu-104? Do328jet? Seems to be the same with slats. There seems a way around them, if designed so. IL-62 lacks slats, i believe DC-8 as well. Did all 707s and DC8s have reversers?

Hard to get to your conclusions.


Iirc Crossair paid Embraer extra to get their ERJ without reversers to safe on maintenance, which consequently became an option.
Swiss made the news with those twice for not stopping, 1x HAJ, 1x NUE.

abcgogo wrote:
Landing on contaminated runways (ice, water, snow, oil, etc


You have to be able to land and stop without thrust reversers, since you only find out if they work or not when you deploy them. So the sort of condition where you can't safely land without them would close the runway for you anyways.
Now does it improve safety margins, for example when contamination goes unnoticed, very probably yes, is it always the best investment of weight to improve safety... not so sure.

Best regards
Thomas
Well, there is prophecy in the bible after all: 2 Timothy 3:1-6
 
mmo
Posts: 1963
Joined: Thu Apr 18, 2013 3:04 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 11:13 am

To be honest, and to answer most of your observations, it boils down to cost vs. benefit. Engineers could design an aircraft that would never crash, but the cost would be prohibitive and no one would ever be able to afford it. During the safety analysis, cost vs benefit (lives saved) is a big issue. While having a "fool" proof aircraft is great, just how much will it cost to get there.

Your first comment leaves me a little confused. Every flight does not go with full tanks. Part of the certification process is to make sure the aircraft (transport category) can land at its max takeoff weight. Its max landing weight is for normal operations, in the event of an engine failure on takeoff, the aircraft can come right back and land. So, your first point is a non-issue.

Your comments about autoland/parachute and having Cat IIIB at every airport. Again the cost is a major issue due to the certification requirements of the aircraft and airport. In addition, not every airport can have a CATIII approach due to not being suitable due to terrain or obstacles so CAT II might be the only approach available.

Finally, in a perfect world, every regulatory body would be harmonized with each other. In reality, it doesn't work like that and your complaint about cabin lights is a perfect example. Some regulatory bodies allow it and some don't.
If we weren't all crazy we'd all go insane!
 
11C
Posts: 128
Joined: Mon Jun 17, 2019 2:25 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 1:55 pm

abcgogo wrote:
Hello everyone, I have been a long time lurker but decided to register on airliners.net now. I am not an insider of the aviation industry but am an extremely curious aviation-enthusiast (avgeek). Apologies if I make any mistakes/misunderstandings in any of my post, because I am a noob/average on technical matters. With that said, let me start with the topic at hand.

I have noticed the following shortfalls in aviation safety and wondered why have the various aviation authorities/safety-agencies overlooked them and allowed the manufacturers to get away with them. The list are as follows:--
------------------------------

1) Lack of fuel-dumping systems on small aircraft, especially the business-jets and even on the RJs and narrowbody airliners like A320-family and 737-family. Even the latest long-range large business-jets like Gulfstream's G650ER, G700 and Bombardier's Global-7500 lack this safety feature. Check out this video, where the pilot of a fully loaded Global-6000 tells the ATC that he needs to burn fuel for 5 hours just to reach Maximum-Landing-Weight (MLW).
https://youtu.be/_2YsabrDEug?t=250

Is it possible to land safely with 99% or even 80% fuel load (even if it may lead to requiring lots of intensive maintenance after landing) ? I was under the impression that the maximum safest landing can be done only when the aircraft is just above Maximum-Landing-Weight (MLW), say 20% above MLW....otherwise, it would lead to a crash landing where the landing gear would collapse (unable to handle the weight) and the heavily loaded full tanks in the wings would burst open causing a fireball explosion that could severely-injure/kill everybody on board.....something like the DC-10 crash at Sioux-City.

https://youtu.be/b6JW4NuI5GM?t=2620
------------------------------

2) Why aren't light-jets equipped with thrust reversers or a suitable alternative ? All airliners and the medium size (& above) business jets have it, giving them three ways of slowing down (thrust reversers, wheel brakes, spoilers), whereas the very-light & light-jets are restricted to just two ways of slowing down (wheel brakes, spoilers) which seems to be risky considering the high landing speeds of the jet aircaft. If the brakes fail for any reasons, then only God can save the occupants of the light-jets. Landing on contaminated runways (ice, water, snow, oil, etc.) is risky if we don't have reverse thrust, after all if it was unnecessary the airlines would be the first one to make do without them just to save costs.
------------------------------

3) Why aren't active-feedback joysticks present in aircraft ? Only recently we have seen Gulfstream install "active-sidesticks" which move in-sync with each other giving the pilots feedback of what the other pilot (& autopilot too, if i'm not mistaken) is doing. Even the trainer versions of the Cold-War era fighter aircraft had joysticks which were connected. I understand that fly-by-wire is a different beast, but how am I supposed to accept the argument that companies who could program computers to fly airplanes, could not program the joysticks to move in-sync and give feedback to pilots ? It's shocking that no agency across the world had raised objections to Airbus and other manufacturers offering only ordinary joysticks which is a safety hazard IMHO. Check out these two videos, one of the MiG-23UB instructor's cockpit and of the Gulfstream sidesticks.
https://youtu.be/MRNk6SvrDAk?t=48
https://youtu.be/vXhCJYWvwd0?t=45
------------------------------

4) Why aren't Enhanced-Vision-System, Sythetic-Vision-System or the best of both worlds, Combined-Vision-Systems, made mandatory on all aircraft right from helicopters to propellor-aircraft to large airliners ? Such an important feature (CVS) would greatly benefit safety of aviation. Recently, we saw the news of Kobe-Bryant's unfortunate crash. Maybe crashes like this could have been avoided had the safety agencies enforced mandatory installation of CVS, just like how ADS-B Out has been made mandatory (if i'm not mistaken).
------------------------------

5) Why aren't aircraft equipped with runflat or bulletproof tyres (if that is possible), to ensure that even in case of a puncture the aircraft is still under control and safely comes to a halt rather than skidding off the runway or worse ?
------------------------------

6) Why aren't all airliners equipped with inbuilt airstairs (like on Ryanair-aircraft and ACJ/BBJ) so that they do not have to depend on airport airstairs ? Such a mandatory feature would increase the versatility of airliners usage where in an urgent situation (not emergency), the passengers & crew can quickly embark/disembark instead of damaging the aircraft by using the emergency slides. An example of this is the evacuation of civillians in Yemen done by Air-India (at behest of the Govt-of-India) which sent two A321 aircraft. Luckily for AI, there were stairs available at the war-stricken airport, had it been damaged/destroyed, then there would have been no way for Air-India to be able to board it's aircraft and the civillians would have been left stranded in Yemen. Check out this picture, if they had inbuilt airstairs, then that would have been an additional peace-of-mind factor for them. We have seen many such evacuations where by sheer luck or good planning, there have always been airstairs available, but what if one day the luck/planning runs out and there are no airstairs ? How are civillians going to be evacuated then ?
https://1ep6sa1jro642bl0n01shxzi-wpengi ... EN-FLT.jpg
https://www.airliners.net/photo/Ryanair ... /1277441/L
------------------------------

7) It is a well known safety-measure and/or regulation that cabin lights must be dimmed just-before, during and just-after takeoff-&-landing when the flight is operating in low/no sunlight hours. This is to ensure that in case of any emergency, the passengers & crew can be more aware of their surroundings and their eyes can easily adjust to the dull/dark surroundings which will help them escape instead of being "blinded" (for lack of a better term) by the darkness in case cabin lights are kept bright. Inspite of this being known, I have observed quite a few airlines and business jets operating with cabin lights at 70-100% brightness in low/no sunlight conditions. Why isn't any agency cracking down on such unsafe behaviour ? Check out these videos where you can see this irresponsible behaviour.
https://youtu.be/V3L3mYwgoGI?t=142
https://youtu.be/ejypZ7oSKSg?t=503
------------------------------

8) Why don't aircraft have proximity sensors installed on their outermost parts (such as nosecone, winglets, tails, etc) and on various parts of their fuselage ? These sensors can function similar to parking-sensors in cars (but actively rather than passive) where one of the Multi-Function-Display's (MFD) in the cockpit can show the aircraft diagram and all the sensors readings just like how infotainment systems in cars show the diagram of the car and proximity of objects based on sensor reading. Installing such equipment can ensure incidents like one aircraft's wingtip hitting another aircraft's tail are avoided because the sensors in both planes will start beeping loudly in the cockpit warning the crew of both aircraft of possible collision. All sorts of advanced technology are fitted on aircraft yet something so basic cannot be done ? I am surprised. Check out these luxury cars, they actively monitor their surroundings and starts beeping whenever anything gets too close to the car (even in traffic). Why can't this be done by any aircraft manufacturer ?
https://youtu.be/mERCXWIJFnE?t=97
https://youtu.be/8LY8Rz5aM6A?t=41
------------------------------

9) Why aren't small aircraft mandatorily equipped with autoland and parachutes (like Cirrus, Piper aircraft) when it is well known that pilots of such aircraft tend to be hobbyists rather than full time professional pilots who don't have the vast experience to deal with emergencies or mistakes they might face ? It might increase the costs slightly but it also increases the safety a lot more, thereby reducing crashes. Also, the costs might be reduced due to the "economies-of-scale" factor.
https://youtu.be/gBCUQlF3MMU
https://youtu.be/IcVuubU4BTU
------------------------------

10) Why aren't all airports and aircraft equipped with CAT-3B safety feauture ? Even the famous Gulfstream-G650 does not have it. Isn't it a bit too dangeorous to depend only on EVS/SVS/CVS, instead of the much more safer and more important CAT-3B ? If all airports and aircraft have this feature, a lot of diversions, "Controlled-Flight-Into-Terrain" (CFIT) might be avoided due to pilots being more confident in the aircraft making a safe landing.
------------------------------

11) Why do aviation authorities & safety agencies not take any preventive action, instead only taking reactive action ? Nobody bothered with so many obvious flaws in various aircraft over the years, reacting only when a crash (or two or more) happened. In USA, the FAA wakes up only after something goes wrong, in India the DGCA doesn't care inspite of the numerous engine-failures on Indigo's A320neo (Pratt-&-Whitney engines), and globally nobody raised any of the above 10-points I have mentioned. Why such a lax attitude to safety ? In one of India's languages "Hindi", we have a phrase for this careless/carefree attitude called "Chalta-hai"-attitude. Another term/phrase from Hindi, "Jugaad" (quick fix), is also soemthing I can apply to the aviation agencies of the world who only want to do some face-saving, quick-fix measures after a disaster has happened.
https://www.quora.com/What-is-chalta-hai
http://en.wikipedia.org/wiki/Jugaad
------------------------------

I am sure there are more problems, mistakes, oversights, etc. which I might not know about but industry insider would know. Again, apologies for any mistakes/misunderstandings but please do correct me instead of hating.

Thanks in Advance,
abcgogo


For all the reasons people have listed, none of the items you cite are “obvious safety deficiencies,” with the possible exception of the cabin lights example. They are all informed choices, essentially, risk management. Risk is the element that cannot be eliminated from the equation. But informed decisions have to be informed by foreseeing as many risks as possible, and that’s why a voice like yours is always needed. I’m surprised you didn’t mention the design choice that Boeing made with the AOA sensors on the Max. As to the proactive nature, or lack thereof, inherent in our regulatory agencies, I’ll leave that one for someone else.
 
GalaxyFlyer
Posts: 5282
Joined: Fri Jan 01, 2016 4:44 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 2:03 pm

1/. There was no need to remain airborne for 5 hours to burn down to MLW. FAR 25 certification requires landing capability at MTOGW at reduced sink rate. Just an overweight inspection.
 
CriticalPoint
Posts: 988
Joined: Thu Jan 19, 2017 5:01 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 2:03 pm

Antaras wrote:
abcgogo wrote:
1) Lack of fuel-dumping systems on small aircraft, especially the business-jets and even on the RJs and narrowbody airliners like A320-family and 737-family.

Last year I went on a A321neo. Seems like it is dumping fuel. Have a look a this picture (sorry for the bad quality as I was seating on the aisle-seat, alongside with HAN's foggy weather at that moment).
Look, you may see a light-brown liquid flying from the position of the wing:
Image
[sorry, even I can't even see it :(]
About the 737, have a look at this fancy picture of Jetstar Pacific's 737-400

Well I believe that airframe was dumping fuel :roll:


That’s condensation......if you do t know what you are talking about then please refrain from comment.
 
User avatar
nighthawk
Posts: 4879
Joined: Sun Sep 16, 2001 2:33 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 3:05 pm

For each point that you claim is a safety issue, please give one example where it resulted in an accident in the last 10 years. Better yet, one that claimed a fatality. If you can't then it isn't a safety issue.
 
VSMUT
Posts: 3966
Joined: Mon Aug 08, 2016 11:40 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 3:54 pm

abcgogo wrote:
1) Lack of fuel-dumping systems on small aircraft, especially the business-jets and even on the RJs and narrowbody airliners like A320-family and 737-family. Even the latest long-range large business-jets like Gulfstream's G650ER, G700 and Bombardier's Global-7500 lack this safety feature.

Is it possible to land safely with 99% or even 80% fuel load (even if it may lead to requiring lots of intensive maintenance after landing) ? I was under the impression that the maximum safest landing can be done only when the aircraft is just above Maximum-Landing-Weight (MLW), say 20% above MLW....otherwise, it would lead to a crash landing where the landing gear would collapse (unable to handle the weight) and the heavily loaded full tanks in the wings would burst open causing a fireball explosion that could severely-injure/kill everybody on board.....something like the DC-10 crash at Sioux-City.


As others touched on, aircraft are certified to land at MTOM, it just isn't guaranteed that the aircraft won't sustain minor damage or fatigue if you do so.

Landing overweight does not result on Sioux-City style crashes. That crash was caused because the aircraft was barely under control. It struck with the wing first, spilling out fuel which ignited. The aircraft then cartwheeled and broke apart. Besides, the DC-10 does have fuel dump. I think it should also be noted that the fuel vapors in an empty tank are more flammable than jet fuel in its liquid form.


abcgogo wrote:
2) Why aren't light-jets equipped with thrust reversers or a suitable alternative ? All airliners and the medium size (& above) business jets have it, giving them three ways of slowing down (thrust reversers, wheel brakes, spoilers), whereas the very-light & light-jets are restricted to just two ways of slowing down (wheel brakes, spoilers) which seems to be risky considering the high landing speeds of the jet aircaft. If the brakes fail for any reasons, then only God can save the occupants of the light-jets. Landing on contaminated runways (ice, water, snow, oil, etc.) is risky if we don't have reverse thrust, after all if it was unnecessary the airlines would be the first one to make do without them just to save costs.


Brakes aren't as simple as you suggest. I can only speak for my own plane, but it seems pretty common. The brakes can't "just" fail. We have 4 main wheels, each with their own brake. Each brake can be run off of 2 separate hydraulic systems, one of which contains a pressurized reservoir with enough pressure and hydraulic fluid to brake the aircraft even if all the remaining hydraulic fluid is gone. There are layers upon layers of redundancy.


abcgogo wrote:
4) Why aren't Enhanced-Vision-System, Sythetic-Vision-System or the best of both worlds, Combined-Vision-Systems, made mandatory on all aircraft right from helicopters to propellor-aircraft to large airliners ? Such an important feature (CVS) would greatly benefit safety of aviation. Recently, we saw the news of Kobe-Bryant's unfortunate crash. Maybe crashes like this could have been avoided had the safety agencies enforced mandatory installation of CVS, just like how ADS-B Out has been made mandatory (if i'm not mistaken).


Because they are an expensive distraction that takes away the pilots focus if he isn't trained and disciplined enough. More systems aren't necessarily safer. All the systems you noted are related to landing in poor visibility conditions. The safest and simplest method in such conditions is to simply divert somewhere else where the weather is better.

KISS: Keep It Simple, Stupid.


abcgogo wrote:
5) Why aren't aircraft equipped with runflat or bulletproof tyres (if that is possible), to ensure that even in case of a puncture the aircraft is still under control and safely comes to a halt rather than skidding off the runway or worse?


I am pretty sure aircraft tires are already of a better quality than any automotive runflat tire. There are a couple of reasons why we don't have runflat tires however:

Runflat tires are severely restricted in speed. Not very useful to have an 80 km/h speed restriction on a plane that lands at 200 km/h.

Tires that burst on landing often completely disintegrate. There won't be enough wheel left to run flat on.

Almost all commercial aircraft have wheels set in pairs of 2, 4 or 6. If one bursts, the remaining wheels can and will take the load.

And finally, the best remedy to burst tires is to replace them before they get too worn out.


abcgogo wrote:
6) Why aren't all airliners equipped with inbuilt airstairs (like on Ryanair-aircraft and ACJ/BBJ) so that they do not have to depend on airport airstairs ? Such a mandatory feature would increase the versatility of airliners usage where in an urgent situation (not emergency), the passengers & crew can quickly embark/disembark instead of damaging the aircraft by using the emergency slides. An example of this is the evacuation of civillians in Yemen done by Air-India (at behest of the Govt-of-India) which sent two A321 aircraft. Luckily for AI, there were stairs available at the war-stricken airport, had it been damaged/destroyed, then there would have been no way for Air-India to be able to board it's aircraft and the civillians would have been left stranded in Yemen. Check out this picture, if they had inbuilt airstairs, then that would have been an additional peace-of-mind factor for them. We have seen many such evacuations where by sheer luck or good planning, there have always been airstairs available, but what if one day the luck/planning runs out and there are no airstairs ? How are civillians going to be evacuated then?


That is not really a safety deficiency, is it?

If you need to evacuate at the gate, you pop the slides.

Air India coordinated before the Yemeni evacuation flight to ensure that steps were available.


abcgogo wrote:
7) It is a well known safety-measure and/or regulation that cabin lights must be dimmed just-before, during and just-after takeoff-&-landing when the flight is operating in low/no sunlight hours. This is to ensure that in case of any emergency, the passengers & crew can be more aware of their surroundings and their eyes can easily adjust to the dull/dark surroundings which will help them escape instead of being "blinded" (for lack of a better term) by the darkness in case cabin lights are kept bright. Inspite of this being known, I have observed quite a few airlines and business jets operating with cabin lights at 70-100% brightness in low/no sunlight conditions.


This is actually a valid point. I have also noted that US airlines allow passengers to have the blinds closed during takeoff and landing.


abcgogo wrote:
8) Why don't aircraft have proximity sensors installed on their outermost parts (such as nosecone, winglets, tails, etc) and on various parts of their fuselage ? These sensors can function similar to parking-sensors in cars (but actively rather than passive) where one of the Multi-Function-Display's (MFD) in the cockpit can show the aircraft diagram and all the sensors readings just like how infotainment systems in cars show the diagram of the car and proximity of objects based on sensor reading. Installing such equipment can ensure incidents like one aircraft's wingtip hitting another aircraft's tail are avoided because the sensors in both planes will start beeping loudly in the cockpit warning the crew of both aircraft of possible collision. All sorts of advanced technology are fitted on aircraft yet something so basic cannot be done ? I am surprised. Check out these luxury cars, they actively monitor their surroundings and starts beeping whenever anything gets too close to the car (even in traffic). Why can't this be done by any aircraft manufacturer?


We don't have it, because there shouldn't be anything on the maneuver area to begin with. If we need it, there are several layers that already failed at their job.


abcgogo wrote:
9) Why aren't small aircraft mandatorily equipped with autoland and parachutes (like Cirrus, Piper aircraft) when it is well known that pilots of such aircraft tend to be hobbyists rather than full time professional pilots who don't have the vast experience to deal with emergencies or mistakes they might face ? It might increase the costs slightly but it also increases the safety a lot more, thereby reducing crashes.


Parachutes are actually really restrictive in their use. I've been told that the parachute in the Cirrus only works when the aircraft faces upright and is almost completely straight and level. Open it at any other attitude, and the aircraft will only become entangled in it. It was actually fitted only as a means to certify it because it inhibits really poor spin characteristics. There is also a lot of evidence that pilots flying parachute equipped aircraft take more unnecessary risks because they trust the parachute to save them, that result in way more fatal accidents than normal aircraft.


abcgogo wrote:
10) Why aren't all airports and aircraft equipped with CAT-3B safety feauture ? Even the famous Gulfstream-G650 does not have it. Isn't it a bit too dangeorous to depend only on EVS/SVS/CVS, instead of the much more safer and more important CAT-3B ? If all airports and aircraft have this feature, a lot of diversions, "Controlled-Flight-Into-Terrain" (CFIT) might be avoided due to pilots being more confident in the aircraft making a safe landing.


Like point no. 4, CAT-III is complex and requires regular training. By far the safest option is to not land. Go somewhere where it is safe. KISS.
 
WayexTDI
Posts: 1704
Joined: Fri Sep 21, 2018 4:38 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 5:01 pm

abcgogo wrote:
6) Why aren't all airliners equipped with inbuilt airstairs (like on Ryanair-aircraft and ACJ/BBJ) so that they do not have to depend on airport airstairs ? Such a mandatory feature would increase the versatility of airliners usage where in an urgent situation (not emergency), the passengers & crew can quickly embark/disembark instead of damaging the aircraft by using the emergency slides. An example of this is the evacuation of civillians in Yemen done by Air-India (at behest of the Govt-of-India) which sent two A321 aircraft. Luckily for AI, there were stairs available at the war-stricken airport, had it been damaged/destroyed, then there would have been no way for Air-India to be able to board it's aircraft and the civillians would have been left stranded in Yemen. Check out this picture, if they had inbuilt airstairs, then that would have been an additional peace-of-mind factor for them. We have seen many such evacuations where by sheer luck or good planning, there have always been airstairs available, but what if one day the luck/planning runs out and there are no airstairs ? How are civillians going to be evacuated then ?
https://1ep6sa1jro642bl0n01shxzi-wpengi ... EN-FLT.jpg
https://www.airliners.net/photo/Ryanair ... /1277441/L

The 737 built-in airstair is a heavy (from memory, 300 lbs or so), expensive ($1/4 million) and maintenance intensive (as it wasn't meant to be used 10 times or so per day) piece of equipment.
Furthermore, they are slow to deploy and require electrical power (AC or DC, DC is even slower).

Emergency Evacuation Slides take just a few seconds to deploy, can (must) work in case of power failure and in extreme cold. During deployment, you do not damage the aircraft or the slide; slides are tested regularly and repacked on a calendar basis. Repacking is rather cheap (less than $10K per slide).
Lastly, slides are much quicker at evacuating passengers, are able to evacuate physically disabled passengers (they just slide down and don't have to walk down the stairs) and can double as rafts in case of water landing.
 
User avatar
Revelation
Posts: 23446
Joined: Wed Feb 09, 2005 9:37 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 5:53 pm

I would add that the manufacturers have made the larger planes more safe via higher levels of redundancy and added features such as fuel dump because the larger planes carry more people for longer periods of time thus create higher risk.

The distinction is now more blurred because what used to be thought of as smaller shorter ranged aircraft such as A320 or 737 are now crossing oceans and making flights approaching 8 hours and > 3000 mi routinely.
Wake up to find out that you are the eyes of the world
The heart has its beaches, its homeland and thoughts of its own
Wake now, discover that you are the song that the morning brings
The heart has its seasons, its evenings and songs of its own
 
blockski
Posts: 682
Joined: Wed Jun 15, 2016 8:30 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 5:56 pm

I would agree with the comments about cost/benefit. I would also note that there's a difference between a 'safety' agency with safety as their sole focus (like the NTSB) and a regulatory one with a broader mandate (like the FAA).
 
Wacker1000
Posts: 204
Joined: Tue Jan 07, 2014 6:36 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Thu Apr 09, 2020 6:10 pm

None of these are safety deficiencies - that is why they are ok.

There could be an argument made that some are operational limitations but that comes down to what operators are willing to pay for.
 
abcgogo
Topic Author
Posts: 29
Joined: Wed Mar 18, 2020 4:57 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 6:55 am

I logged in after a long time and was surprised to see so many updates on my thread which I thought was missed out by the community. Thanks a lot to all the members who have replied to my thread, I learnt a lot of the reasoning behind why the decisions to overlook points I mentioned have been made ! :)

Now I would like to make some clarifications regarding my original post.

1) I was curious to know if aircraft could safely land even if they are well above MLW. I came across that youtube video of the Vistajet Global-6000 pilot telling ATC that he needed 5 hours to burn fuel just to reach MLW. This along with seeing various instances of aircaft choosing to fly circuits and dump fuel instead of landing ASAP made me wonder if it was impossible or unsafe to land at say MTOW. I was under the assumption that in case an aircraft tries to land at MTOW (or well above MLW), it's landing gear would be unable to bear the weight and would collapse, which could damage the wings, cause fuel leaks and hence a Sioux-City style fireball. I know aircraft have landed without landing gears, but those were planned landings (meaning gear was not in lowered-position before touchdown), unlike the "gear-collapsed" idea what I am considering where the gear collapses and rips massive holes into the wings and fuel tanks.

2) Yes I know at some point cost is an issue. But if we look at it that way, a lot of the older generation aircraft were/are quite simple in their features relative to modern aircraft. Isn't safety a more important focus at least 95% of the time ? If a person/organization is really worried about cost they can probably purchase the used older simple aircraft or can simply buy used versions of the modern-aircraft. Not sure about the economics of it all since I am no insider in Aviation-business so please excuse my mistakes if any.

3) I noticed incidents of wing-strike (where one aircraft's wingtips hit another aircraft) happens way too many times inspite of their being so many established procedures and experience at airports. Hence my idea for this "aircraft-parking-sensor" which although sounds silly, is just another layer of protection for the aircraft & people in it. After all, even if mistakes are made by wing-walkers or others, it does not have to end so badly (aircraft unusable, costly repairs, etc.) when it can be prevented with such simple solution. Aircraft have such complex systems on board, so I think it must be simple for them to install parking-sensors type of system.

4) Regarding airstairs, the issue in the Yemen-evacuation was that the Indian-Govt could not send military cargo aircraft like C-17, Il-76, etc. because it was clearly warned by the Houthis & Saudis (IIRC) that these aircraft could be mistaken as military aircraft of Saudi/UAE/USA and hence be fired upon. Houthis would assume it was a Saudi/UAE/USA aircraft that is their enemy and could attack it. Hence the Indian-Govt sent AI aircraft, that too it could not send the widebodies like 777 or 747 because (I assume) the ground-airstairs were not capable of handling the tall aircraft. Please see this video, where an official explains why they couldn't use military cargo aircraft (he talks about C-17 but same concept applies to all IAF-cargo aircraft since they have same livery & look very similar to non-avgeeks).
https://youtu.be/MonsK7AEbBI?t=243

I know private airlines might not find it feasible to install airstairs, but the national-carriers (Air-India, Singapore-Airlines, Lufthansa, Air-China, JAL/ANA, etc.) should have it IMHO because they might have to evacuate their citizens at any time due to any issue (as we saw in Gulf-War and now Coronavirus pandemic). The reason I mention airstairs is because unlike evacuation slides which are "one-way" (meant only for rapid-disembarking), the airstairs are "two-way" meaning they can be used to embark/disembark passengers which is a useful feature in evacuation zones.

5) The tire issue is because I have observed the nose-gear has only two-tyres at most and sometimes even there is a possibility of multiple tyre failures (due to puncture or very hard landing or anything really) in main landing gear. Just think if the nose-gear tyres fail, then the aircraft steering capabilities are lost at low/medium/slightly-high speeds which means the aircraft might not be able to turn on the ground and careen into an obstacle (wing-strike, head on collision, etc.). If this happens when the aircraft is turning into a gate or is turning on a taxiway near other aircraft or airport-equipment, then even emergency braking might not be enough to stop the aircraft in time. Also, if the entire left main landing gear tyres fail, then the aircraft might have a tendency to veer to the left even though the nose & right landing gear tyres are alright. I know these are edge cases with low chance of occurring, but there is a possibility of such things happening and hence my question to know whether it was possible or not to improve tire safety.

6) Yes I know I called even the regulatory agencies (like FAA, DGCA, etc.) as Safety-Agencies (like NTSB) but what is the point of mere regulations if all they end up doing is certifying unsafe aircraft ? The 737-MAX was certified by many such agencies across the world and what good did that do for everyone ? The concept of "Prevention-is-better-than-cure" is very important and I know it is difficult to go through diagrams, manuals, etc of these complex machines. But I as a layman with litle avgeek knowledge have pointed out such obvious things, so surely the experts would know much better. Quite a few of the "regulations-were-written-in-blood" could have been avoided I suppose, but then again what do I know (not being sarcastic here, but genuinely wondering).

7) Another point I would like to raise is why don't helicopters have two tail rotors for redundancy ? We have seen helicopters spinning due to tail rotor failure, so is there no way to prevent this problem ? Does installing two tail rotors add too much weight and/or complexity such that it becomes unusable helicopter ? Maybe they can have two rotors vertically stacked on the same side (one on upper tailfin, one on lower tailfin) and one of the rotors can be kept at idle power while other does the regular job. In case the running rotor fails or gets damaged, they can shut down the damaged rotor and quickly power up the second rotor to prevent any spin/rotation (not sure what it is called) problems.
 
VSMUT
Posts: 3966
Joined: Mon Aug 08, 2016 11:40 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 8:14 am

abcgogo wrote:
I was under the assumption that in case an aircraft tries to land at MTOW (or well above MLW), it's landing gear would be unable to bear the weight and would collapse, which could damage the wings, cause fuel leaks and hence a Sioux-City style fireball. I know aircraft have landed without landing gears, but those were planned landings (meaning gear was not in lowered-position before touchdown), unlike the "gear-collapsed" idea what I am considering where the gear collapses and rips massive holes into the wings and fuel tanks.


Which of course won't happen, because the gear could bear the weight prior to takeoff.


abcgogo wrote:
2) Yes I know at some point cost is an issue. But if we look at it that way, a lot of the older generation aircraft were/are quite simple in their features relative to modern aircraft. Isn't safety a more important focus at least 95% of the time ? If a person/organization is really worried about cost they can probably purchase the used older simple aircraft or can simply buy used versions of the modern-aircraft. Not sure about the economics of it all since I am no insider in Aviation-business so please excuse my mistakes if any.


Old aircraft are more costly to run and require more maintenance. In Europe, thanks to EU261, skimping on maintenance is not worth it, because every technical delay over 3 hours means paying out at least €250 to each passenger.

But I challenge your notion that simple is more unsafe. Simple is more safe. Every time you put a fancy new gadget in an airplane, it means one more thing the pilots must learn to use and train with on a regular basis. What is most unsafe, a CAT I aircraft only flown under CAT I conditions, or a CAT II aircraft flown under CAT II conditions with a crew that isn't proficient in it?


abcgogo wrote:
3) I noticed incidents of wing-strike (where one aircraft's wingtips hit another aircraft) happens way too many times inspite of their being so many established procedures and experience at airports. Hence my idea for this "aircraft-parking-sensor" which although sounds silly, is just another layer of protection for the aircraft & people in it. After all, even if mistakes are made by wing-walkers or others, it does not have to end so badly (aircraft unusable, costly repairs, etc.) when it can be prevented with such simple solution. Aircraft have such complex systems on board, so I think it must be simple for them to install parking-sensors type of system.


Take a look at this video:
https://www.youtube.com/watch?v=SpLd-t1tcJU

The CRJ pushed back into the path of an A380. How much time do you think a parking sensor would have given the A380 pilots to bring the aircraft to a halt? My guess is, not enough.

In one way or another, many strikes involve shut-down aircraft being towed around. How would the sensor work when the aircraft is off?

If all the procedures with wing-walkers etc. failed, why would a procedure involving parking sensors be any better?

Statistically these incidents are very rare. You may think you see a lot, but reality is that this is out of a global fleet of over 25.000 aircraft.


abcgogo wrote:
4) Regarding airstairs, the issue in the Yemen-evacuation was that the Indian-Govt could not send military cargo aircraft like C-17, Il-76, etc. because it was clearly warned by the Houthis & Saudis (IIRC) that these aircraft could be mistaken as military aircraft of Saudi/UAE/USA and hence be fired upon. Houthis would assume it was a Saudi/UAE/USA aircraft that is their enemy and could attack it. Hence the Indian-Govt sent AI aircraft, that too it could not send the widebodies like 777 or 747 because (I assume) the ground-airstairs were not capable of handling the tall aircraft. Please see this video, where an official explains why they couldn't use military cargo aircraft (he talks about C-17 but same concept applies to all IAF-cargo aircraft since they have same livery & look very similar to non-avgeeks).

I know private airlines might not find it feasible to install airstairs, but the national-carriers (Air-India, Singapore-Airlines, Lufthansa, Air-China, JAL/ANA, etc.) should have it IMHO because they might have to evacuate their citizens at any time due to any issue (as we saw in Gulf-War and now Coronavirus pandemic). The reason I mention airstairs is because unlike evacuation slides which are "one-way" (meant only for rapid-disembarking), the airstairs are "two-way" meaning they can be used to embark/disembark passengers which is a useful feature in evacuation zones.


Define "national"? Lufthansa isn't owned by the German state. The Indian government is looking to privatize Air India. ANA certainly isn't state owned and I don't think JAL is either. Why should some privately held companies be forced to carry heavy and expensive equipment when others should not?

Moving on, how often has it actually been a problem that you couldn't find a functional stair or ladder at a functional airport? The Air India evacuation from Yemen actually worked, didn't it?

Lets play with the idea that for some reason the Saudi coalition had decided to bomb the [completely worthless to any military or resistance movement] airstairs:
Getting in contact with a local welder to put something together is way cheaper and faster.
Or just send something that already has built-in stairs, like a 737, ATR, CRJ, Dash-8 or MD-80.

You are looking for an issue where there is none. What do you think will be bombed first, the stairs or the runway?


abcgogo wrote:
Just think if the nose-gear tyres fail, then the aircraft steering capabilities are lost at low/medium/slightly-high speeds which means the aircraft might not be able to turn on the ground and careen into an obstacle (wing-strike, head on collision, etc.). If this happens when the aircraft is turning into a gate or is turning on a taxiway near other aircraft or airport-equipment, then even emergency braking might not be enough to stop the aircraft in time.


Trust me, an aircraft without wheels on one or more of the gears stops very fast.


abcgogo wrote:
Also, if the entire left main landing gear tyres fail, then the aircraft might have a tendency to veer to the left even though the nose & right landing gear tyres are alright.


That would also happen on run-flat wheels.


abcgogo wrote:
6) Yes I know I called even the regulatory agencies (like FAA, DGCA, etc.) as Safety-Agencies (like NTSB) but what is the point of mere regulations if all they end up doing is certifying unsafe aircraft ? The 737-MAX was certified by many such agencies across the world and what good did that do for everyone ? The concept of "Prevention-is-better-than-cure" is very important and I know it is difficult to go through diagrams, manuals, etc of these complex machines. But I as a layman with litle avgeek knowledge have pointed out such obvious things, so surely the experts would know much better. Quite a few of the "regulations-were-written-in-blood" could have been avoided I suppose, but then again what do I know (not being sarcastic here, but genuinely wondering).


Not every regulatory agency in the world is as useless as the FAA during the 737MAX development. They are supposed to follow up on the design and be critical. Up until about 10 years ago, the world knew they could trust the FAA, that is why EASA all the national CAAs trusted the FAA to certify it. Unfortunately, issues are often only uncovered when something bad happens.


abcgogo wrote:
7) Another point I would like to raise is why don't helicopters have two tail rotors for redundancy ? We have seen helicopters spinning due to tail rotor failure, so is there no way to prevent this problem ? Does installing two tail rotors add too much weight and/or complexity such that it becomes unusable helicopter ? Maybe they can have two rotors vertically stacked on the same side (one on upper tailfin, one on lower tailfin) and one of the rotors can be kept at idle power while other does the regular job. In case the running rotor fails or gets damaged, they can shut down the damaged rotor and quickly power up the second rotor to prevent any spin/rotation (not sure what it is called) problems.


I can think of a few reasons.

First, look at what causes tail rotor failures. It is either internally in the gear-boxes, so would impact both rotors regardless. Alternatively it is because the pilot impacts something, which lets face it, would probably break both rotors and/or the internal axles and gear boxes too.
Second, you don't "just" keep the rotor on idle power. It is mechanically connected. That would require a clutch, and in this case it would mean clutching-in the rotor while the engines are running at power. You will still have a damaged rotor spinning about, possibly out of balance and spewing wreckage around, which could damage your remaining rotor.

To sum it up, the technical challenges are impossible and the benefits are close to nil. The single biggest safety benefit of such a system would be to make helicopters so expensive to fly, that almost nobody is going to do it.
 
mmo
Posts: 1963
Joined: Thu Apr 18, 2013 3:04 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 9:30 am

I am not sure what you are getting at in your first topic, overweight landings. If the PIC exercises his "emergency authority" he is allowed to land at MTOW (Structural), assuming he has the go-around capability. There are instances where there is a minor problem that does not require the declaration of an emergency where there is no option but to burn off/dump fuel. However, I think you will find most airlines would back the PIC in declaring an emergency to land sooner rather than dumping or burning off fuel. As long as all the parameters are not exceeded all that is required is an overweight landing inspection which takes about 15 minutes. The landing gear, tires, brakes and structure are all good up to the structural limit.

The crash of SwissAir 111, is a good example where the crew should have landed ASAP, but the PIC became fixated in dumping down to MLW.

I have been lucky to work for airlines where the management rarely second-guessed the pilots. If you screwed up, you knew about it but management made it clear just what they expected from their Captains and as long as you complied there was no issue.

Item 4 about airstairs and national carriers. Having worked for SIA, I can assure you Singapore Airlines is not a "national carrier". It is a publicly-traded company and Tameseck Investments, the government sovereign wealth fund is the largest shareholder, SQ would be dropped in an instant if it, during normal operations, had a string of no profits.

Item 5 is very puzzling!! I think you are making a problem where there isn't one. Tell me of one single incident/accident which has been caused by your scenario. On transport type aircraft, it just isn't a problem and I can't think of one single incident which has occured.
If we weren't all crazy we'd all go insane!
 
abcgogo
Topic Author
Posts: 29
Joined: Wed Mar 18, 2020 4:57 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 10:03 am

Thanks for the clarifications and explanations. :)

1) Regarding nose gear tyre failure, I had in mind skids caused due to flat/burst tyres. Something like how cars without ABS cannot turn and brake at same time and just head straight towards the object (see first-link below). However, points by members have made me realize that it was an unnecessary concern. No such incidents have occurred, but there's always a first time for everything which is why I asked about this. The second link below shows a sudden veering of an aircraft (due to nose-gear steering failure) on the runway after landing. Similar veering can happen if all tyres of left/right MLG are burst hence my question whether runflats would help, but members again clarified that regardless of runflats such veering will occur. I learnt that aircraft have an anti-skid system (see third-link) which they use for wet-runways, but my situation was about skids due to tyre-failure during taxiing.
https://youtu.be/hwwXukJaTlM?t=11
https://youtu.be/d9nmrcHbQ8g?t=21
https://youtu.be/tyVwiBUuplk

2) I knew that these airlines are private but had assumed that all the famous carriers of respective nations are asked to serve during times of crisis just like how Air-India and El-Al are frequently used for evacuations by India and Israel respectively. It was from that POV I wondered why these airlines never bothered to install airstairs when they know they could be called upon anytime to evacuate their citizens. I know that runways are usually first targets, but in cases like Yemen we see the airport infrastructure is damaged/destroyed leaving only the runway intact hence the possibility of having airstairs (in any future evacuations) cannot be taken for granted. The reason I mentioned only narrowbody and widebody airliners instead of the regional jets/turboprops is because airliners can carry more people so it is easier to evacuate more people in much lesser time. It is IMHO more risky to run 3-4 flights over a period of 5 days compared to just 1-2 flights over a period 1-2 days. This is because the exposure to risk and chances of things going wrong increases by every few hours in conflict/disaster-zones. Hence IMHO it is better to use largest aircraft possible that can be handled by that airport-runway to evacuate as many people as possible ASAP. But, members here have made good points regarding unnecessary weight and increased costs so I stand corrected.
 
User avatar
lightsaber
Moderator
Posts: 19277
Joined: Wed Jan 19, 2005 10:55 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 1:16 pm

abcgogo wrote:
Thanks for the clarifications and explanations. :)

1) Regarding nose gear tyre failure, I had in mind skids caused due to flat/burst tyres. Something like how cars without ABS cannot turn and brake at same time and just head straight towards the object (see first-link below). However, points by members have made me realize that it was an unnecessary concern. No such incidents have occurred, but there's always a first time for everything which is why I asked about this. The second link below shows a sudden veering of an aircraft (due to nose-gear steering failure) on the runway after landing. Similar veering can happen if all tyres of left/right MLG are burst hence my question whether runflats would help, but members again clarified that regardless of runflats such veering will occur. I learnt that aircraft have an anti-skid system (see third-link) which they use for wet-runways, but my situation was about skids due to tyre-failure during taxiing.
https://youtu.be/hwwXukJaTlM?t=11
https://youtu.be/d9nmrcHbQ8g?t=21
https://youtu.be/tyVwiBUuplk

2) I knew that these airlines are private but had assumed that all the famous carriers of respective nations are asked to serve during times of crisis just like how Air-India and El-Al are frequently used for evacuations by India and Israel respectively. It was from that POV I wondered why these airlines never bothered to install airstairs when they know they could be called upon anytime to evacuate their citizens. I know that runways are usually first targets, but in cases like Yemen we see the airport infrastructure is damaged/destroyed leaving only the runway intact hence the possibility of having airstairs (in any future evacuations) cannot be taken for granted. The reason I mentioned only narrowbody and widebody airliners instead of the regional jets/turboprops is because airliners can carry more people so it is easier to evacuate more people in much lesser time. It is IMHO more risky to run 3-4 flights over a period of 5 days compared to just 1-2 flights over a period 1-2 days. This is because the exposure to risk and chances of things going wrong increases by every few hours in conflict/disaster-zones. Hence IMHO it is better to use largest aircraft possible that can be handled by that airport-runway to evacuate as many people as possible ASAP. But, members here have made good points regarding unnecessary weight and increased costs so I stand corrected.

Everything proposed has a cost. Usually in unneeded weight too.

There is no reason to make flying so expensive it becomes more rare.

Those asking do realize that the risk has to be absurdly low to certify commercial aircraft? Transit needs to fix pedestrian deaths and automobile safety.

1) Any one tire may fail safely (redundancy), unless one tire.. Tires have short allowed service lives for a reason and pressure is checked often. Why add weight?

Most airports have ladder trucks. The weight of stairs doesn't pay off. From a safety standpoint, one can always evacuate by the emergency rope or consume a slide.

Lightsaber
IM messages to mods on warnings and bans will be ignored and nasty ones will result in a ban.
 
blockski
Posts: 682
Joined: Wed Jun 15, 2016 8:30 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 1:36 pm

abcgogo wrote:
6) Yes I know I called even the regulatory agencies (like FAA, DGCA, etc.) as Safety-Agencies (like NTSB) but what is the point of mere regulations if all they end up doing is certifying unsafe aircraft ? The 737-MAX was certified by many such agencies across the world and what good did that do for everyone ? The concept of "Prevention-is-better-than-cure" is very important and I know it is difficult to go through diagrams, manuals, etc of these complex machines. But I as a layman with litle avgeek knowledge have pointed out such obvious things, so surely the experts would know much better. Quite a few of the "regulations-were-written-in-blood" could have been avoided I suppose, but then again what do I know (not being sarcastic here, but genuinely wondering).


The point of regulations is to make things safer. There is always going to be some trade-off on the margins. The only way to make aviation 100% safe with zero risk would be to ban it all together (the ultimate safety regulation!) but that's obviously absurd.

If you can't discuss the trade-offs, then there's not a lot else to discuss. You cannot eliminate risk, but you can manage it. And the critical question to ask is: "is this worth it?"

The 737 MAX is actually a great illustration of that. There are lots of regulatory failures there, but when the failures came into focus, the FAA and others had little choice but to ground the aircraft
 
mxaxai
Posts: 1638
Joined: Sat Jun 18, 2016 7:29 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 1:42 pm

abcgogo wrote:
Thanks for the clarifications and explanations. :)

1) Regarding nose gear tyre failure, I had in mind skids caused due to flat/burst tyres. Something like how cars without ABS cannot turn and brake at same time and just head straight towards the object (see first-link below). However, points by members have made me realize that it was an unnecessary concern. No such incidents have occurred, but there's always a first time for everything which is why I asked about this. The second link below shows a sudden veering of an aircraft (due to nose-gear steering failure) on the runway after landing. Similar veering can happen if all tyres of left/right MLG are burst hence my question whether runflats would help, but members again clarified that regardless of runflats such veering will occur. I learnt that aircraft have an anti-skid system (see third-link) which they use for wet-runways, but my situation was about skids due to tyre-failure during taxiing.
https://youtu.be/hwwXukJaTlM?t=11
https://youtu.be/d9nmrcHbQ8g?t=21
https://youtu.be/tyVwiBUuplk

Burst tyres do happen, and it can be a serious threat if the friction between the rim and the runway creates enough heat to start a fire. Your point regarding cars without ABS is actually a good comparison: An aircraft with burst tyres will keep heading in a straight line - straight down the runway. An aircraft turning on a taxiway is slow enough that it will stop within a few meters if a tyre fails.

Check out a few reports of burst aircraft tyres here: http://avherald.com/h?search_term=burst ... search.y=0 Note that all cases remained controllable.

Also consider the failure mechanism of car and aircraft tyres. A runflat tyre protects against deflation of the tyre. This can happen with car tyres when they are pierced by sharp objects. The runflat tyre will get your car to the closest mechanic. Aircraft tyres that fail on landing or takeoff will often disintegrate completely, and the load is transferred to other tyres, the rims or the gear strut. A runflat tyre won't last much longer than a regular tyre. Image
 
WayexTDI
Posts: 1704
Joined: Fri Sep 21, 2018 4:38 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 3:08 pm

mxaxai wrote:
abcgogo wrote:
Thanks for the clarifications and explanations. :)

1) Regarding nose gear tyre failure, I had in mind skids caused due to flat/burst tyres. Something like how cars without ABS cannot turn and brake at same time and just head straight towards the object (see first-link below). However, points by members have made me realize that it was an unnecessary concern. No such incidents have occurred, but there's always a first time for everything which is why I asked about this. The second link below shows a sudden veering of an aircraft (due to nose-gear steering failure) on the runway after landing. Similar veering can happen if all tyres of left/right MLG are burst hence my question whether runflats would help, but members again clarified that regardless of runflats such veering will occur. I learnt that aircraft have an anti-skid system (see third-link) which they use for wet-runways, but my situation was about skids due to tyre-failure during taxiing.
https://youtu.be/hwwXukJaTlM?t=11
https://youtu.be/d9nmrcHbQ8g?t=21
https://youtu.be/tyVwiBUuplk

Burst tyres do happen, and it can be a serious threat if the friction between the rim and the runway creates enough heat to start a fire. Your point regarding cars without ABS is actually a good comparison: An aircraft with burst tyres will keep heading in a straight line - straight down the runway. An aircraft turning on a taxiway is slow enough that it will stop within a few meters if a tyre fails.

Check out a few reports of burst aircraft tyres here: http://avherald.com/h?search_term=burst ... search.y=0 Note that all cases remained controllable.

Also consider the failure mechanism of car and aircraft tyres. A runflat tyre protects against deflation of the tyre. This can happen with car tyres when they are pierced by sharp objects. The runflat tyre will get your car to the closest mechanic. Aircraft tyres that fail on landing or takeoff will often disintegrate completely, and the load is transferred to other tyres, the rims or the gear strut. A runflat tyre won't last much longer than a regular tyre. Image

One notable example of burst tire on take-off did end very poorly (AF4590, a.k.a. THE Concorde Crash). I agree this was an isolated case due to the design of the aircraft, but to say "all cases [of burst tires] remained controllable" if incorrect; something dramatic could still happen since you never know how dramatically a tire could fail.
 
FGITD
Posts: 752
Joined: Wed Jun 15, 2016 1:44 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 3:28 pm

WayexTDI wrote:
One notable example of burst tire on take-off did end very poorly (AF4590, a.k.a. THE Concorde Crash). I agree this was an isolated case due to the design of the aircraft, but to say "all cases [of burst tires] remained controllable" if incorrect; something dramatic could still happen since you never know how dramatically a tire could fail.



worth noting however that concorde was an unfortunate perfect example of the Swiss cheese problem. A number of individually controllable issues lined up perfectly to end up in disaster.

Your point remains however, even a seemingly minor issue can become something major, regardless of preparation and barriers in place
 
User avatar
Starlionblue
Posts: 19783
Joined: Fri Feb 27, 2004 9:54 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon Apr 20, 2020 11:30 pm

Might I suggest you make one topic for each of these? It is hard to discuss multiple unrelated subjects in one thread.

In general on all of your points, the "deficiencies" only seem so. For every risk, there are mitigations in place. Equipment isn't everything. Procedures and training are a large part of the equation. For example, we don't, as you noted, have proximity sensors. We do, however, have ground controllers, parking position markings, marshallers, taxiway centerlines, and we keep a good lookout.

An exaggeration perhaps, but I'd feel safer in a DC-3 flown by a competent and well-trained crew than in a 787 operated by a startup airline regulated by an agency that is not up to par.


1. Fuel dumping. Any airliner or business jet can land at max takeoff weight. This is a certification requirement. If you have an emergency that requires you to land immediately, e.g. uncontrollable cargo fire, you land immediately regardless of weight. If the emergency is something like an engine failure but the engine is secure, you burn off fuel.

Fuel dumping capability to smaller aircraft would add complexity and weight for very little benefit.

2. Thrust reversers on smaller jets. The majority of braking comes from the brakes. Reversers are a bonus and not even included in performance calculations except on contaminated runways. You could have larger airliners without reversers but you start running into brake temperature issues on short turns.

3. Active-feedback joysticks. (No one on the industry calls them "joysticks".) There is debate on this, for sure, but I'll take this from an Airbus pilot perspective. We don't have moving sidesticks on Airbus because we don't need them and they would add complexity. Airliners are flown based on instruments, not on force feedback. Going a bit deeper, resistance on the Airbus sidestick increases proportionally with deflection, which is perfectly in line with the load factor being proportional to deflection. What would the force "tell" the pilots? Aerodynamic force on the surfaces is not the basis for the control law, so that would be inaccurate feedback. There is no evidence that the absence of force feedback has been detrimental to safety.

4. Enhanced/synthetic vision. This is definitely coming, but we aren't there yet. The benefits for airliners that fly to well equipped airports are marginal at best because we have so many other systems (e.g. ILS) giving situational awareness already. The Kobe Bryant crash was different, as they were flying close to terrain in marginal conditions. Not really where airliners and most business jets spend their time.

5. Run flat tyres. A puncture will not lead to the aircraft skiddding off the runway out of control. The pilots would simply bring it to a stop.

6 . Inbuilt airstairs. These add a lot of weight which now has to be carried on every flight.The evacuation flights you mention are all one off events. Apart from safety related items, you don't carry around a heavy and complex piece of kit for the remote possibility that you might use it once in twenty years.

7. Dimming the cabin. Different countries and operators have different requirements.

8. Proximity sensors. Ground collisions between aircraft are very rare. We have other ways of checking alignment, e.g. taxiway centerline. The installation of sensors would not be cost effective. Cars, on the other hand, are constantly maneuvering in close proximity, and in "uncontrolled" environments.

9. Small aircraft with autoland and parachutes. Autoland is a very expensive piece of kit, and up until a few years ago would be prohibitively expensive to design and install for a small aircraft. Parachutes are heavy and costly, and in the vast majority of cases you're safer trying to fly the plane to the ground.

10) Cat IIIB on all aircraft and airports. Most airports only have CAT IIIB conditions very very rarely. If you have such conditions a few hours a years, it is not worth the very great expense of Cat IIIB capability. For those hours, you simply don't have traffic. And the same goes for aircraft. CFIT is not really related to approach capability. As in, having CAT IIIB capability on the aircraft doesn't make you safe from flying into a hill.

11) Preventive action from authorities. In most countries, authorities take preventive action all the time, through certification, regulation, and inspection. However, the press like to focus on reaction.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
GalaxyFlyer
Posts: 5282
Joined: Fri Jan 01, 2016 4:44 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue Apr 21, 2020 1:19 am

CVS installations, at transport category certification, are very expensive ($500,000) and do not add much in the way of operational advantage, minimums are the same when you’re at airline airports, for example. SVS is similar in cost and no operational advantage. The safety advantage is also not great. You cannot fly in clouds based on SVS, for example, so no help getting Kobe to the game but might have helped the escape maneuver. Mind you, the Pilot still has to able to fly instruments.
 
abcgogo
Topic Author
Posts: 29
Joined: Wed Mar 18, 2020 4:57 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon May 11, 2020 7:55 pm

Ok so got some more ideas/questions which I'd like to know why they were/are not implemented in aviation industry.

1) Why don't aircraft cockpits have a big-size "Level-Checking-Vial" like the one used in level-measurement-tools ? Those bottles with green color liquid that move based on gravity (& hence indiciate whether surface is level or not) is a good idea for aircraft in case instruments have failed or are having errors because it gives the pilot the most basic idea of whether their aircraft is levelled or not . This is especially useful at cloudy & night operations too where it is difficult/impossible to tell which way the aircraft is rolling/pitching due to spatial-disorientation. This seems to be a a quick, error-free (depends on gravity), maintenance-free, system-independent tool. To further make it useful, it can be placed on the dashboard of the cockpit right behind the centre beam (not sure what it is called) which separates the left & right forward cockpit windows and can have a LED (powered by independent battery cell like in a flashlight) so that it is easily visible even at night time. Check out this video of how the bubble in the vial moves when the bottle tilts to left/right, same way it can tell up/down pitch of the aircraft (if placed in vertical position instead of horizontal as shown in video), also see the lava-lamp video (Link-3) to understand my lighting idea.
https://youtu.be/1Hgseq9s6cw?t=588
https://youtu.be/wMJVsRDmHuo?t=155
https://youtu.be/_eA67rfLaL4?t=115

2) Why don't pilots wear Night-Vision goggles at night just like how soldiers wear for their night-operations ? Many times we have seen in past where pilots got spatial-disorientation or confused (usually in addition to instrument problems) and ended up crashing (accident or CFIT). If they had night vision goggles they could at least be able to tell apart things like sea, mountains, trees, etc. The reason I am suggesting this is because many members here have highlighted that installing EVS/SVS/CVS systems is complex and expensive and cannot/will-not be done for older aircraft. The night vision goggle method works for pilots of all types of aircrafts be it balloons, helicopters, airplanes, etc., is cheaper than any EVS/SVS/CVS and is much more lightweight. Sure they pilots might get a bit uncomfortable initially, but with time they might get used to it just like how people who start wearing spectacles feel uncomfortable but eventually get used to it. Check out these videos showing some night vision goggles, pilots can be made to wear them with a headband (see Link-4).
https://youtu.be/d-I4KkxsqYg?t=81
https://youtu.be/dYJ9GWmDq8g?t=290
https://youtu.be/I_nSeS8qMRg?t=276
https://youtu.be/TCdTn7NAL48?t=72

3) Why don't business jet manufacturers extend the fuselage of their aircraft ahead of the front-door to make the cockpit area more spacious so that a comfortable seat can be installed (instead of jumpseat) which can be used by flight-attendant or third-pilot ? In the long-range bizjets (Global-6000/6500/7500, G550/650/600/700, Falcon-7X/8X) there is only 1 crew rest area seat (next to the galley) and the other person (either third-pilot or flight-attendant) has to use the uncomfortable jumpseat (which is suited only for short flights that too for use by instructors/senior-pilots who are training/supervising the trainees/junior-pilots). In the old-days, airliner cockpits had 3-crew and so 3-proper seats were fitted with good space in the cockpit. Now with 2-crew airliners, that seat is replaced by a normal jumpseat & cockpit space is reduced. If the bizjet manufacturers extend the fuselage ahead of the door, they can provide a more spacious (lengthwise) cockpit area where a good 3rd seat can be installed. If manufacturers can extend the fuselage for cabin-purposes (like Challenger->CRJ; Global-6000->Global-7500; G500->G600->G700) then they can certainly do a (relatively) small extension ahead of the front door to make cockpit more spacious (lengthwise) so that a comfortable side-facing seat & storage-space can be installed. It may not be lie-flat seat due to width issues but a nice comfortable recliner seat (like regional business/first-class) is much better than the current jumpseat. Check out the jumpseat at 0:19 (on left side, it is folded) and the single crew-rest seat at 0:49 in the below video (Link-1). Check out pics of current jumpseats in bizjets (Link-2,3). Why doesn't any bizjet manufacturer take the initiative to improve crew-comfort ?
https://youtu.be/6Z6rJ1ooQgo?t=21
https://www.bombardier.com/content/dam/ ... 0.570.jpeg
http://www.jba.aero/wp-content/uploads/ ... mpseat.jpg
 
VSMUT
Posts: 3966
Joined: Mon Aug 08, 2016 11:40 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon May 11, 2020 9:10 pm

abcgogo wrote:
1) Why don't aircraft cockpits have a big-size "Level-Checking-Vial" like the one used in level-measurement-tools ? Those bottles with green color liquid that move based on gravity (& hence indiciate whether surface is level or not) is a good idea for aircraft in case instruments have failed or are having errors because it gives the pilot the most basic idea of whether their aircraft is levelled or not . This is especially useful at cloudy & night operations too where it is difficult/impossible to tell which way the aircraft is rolling/pitching due to spatial-disorientation. This seems to be a a quick, error-free (depends on gravity), maintenance-free, system-independent tool.


No, these are completely useless because of centrifugal forces. I could literally make a bubble level indicate straight and level while banking 90 degrees.


abcgogo wrote:
2) Why don't pilots wear Night-Vision goggles at night just like how soldiers wear for their night-operations ? Many times we have seen in past where pilots got spatial-disorientation or confused (usually in addition to instrument problems) and ended up crashing (accident or CFIT).


Most cases of spatial disorientation happen when you are in or above a cloud layer. Night vision goggles will do nothing to aid you there.



abcgogo wrote:
3) Why don't business jet manufacturers extend the fuselage of their aircraft ahead of the front-door to make the cockpit area more spacious so that a comfortable seat can be installed (instead of jumpseat) which can be used by flight-attendant or third-pilot?


First, it is not a safety deficiency.

Second, it is really expensive, makes no money and provides no benefits to the owner.
 
GalaxyFlyer
Posts: 5282
Joined: Fri Jan 01, 2016 4:44 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon May 11, 2020 9:28 pm

While certainly used on long legs, the average Global flight sector is under 3 hours, fleet wide.
 
User avatar
Moose135
Posts: 3117
Joined: Mon Oct 04, 2004 11:27 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon May 11, 2020 9:41 pm

VSMUT wrote:
abcgogo wrote:
1) Why don't aircraft cockpits have a big-size "Level-Checking-Vial" like the one used in level-measurement-tools ? Those bottles with green color liquid that move based on gravity (& hence indiciate whether surface is level or not) is a good idea for aircraft in case instruments have failed or are having errors because it gives the pilot the most basic idea of whether their aircraft is levelled or not . This is especially useful at cloudy & night operations too where it is difficult/impossible to tell which way the aircraft is rolling/pitching due to spatial-disorientation. This seems to be a a quick, error-free (depends on gravity), maintenance-free, system-independent tool.


No, these are completely useless because of centrifugal forces. I could literally make a bubble level indicate straight and level while banking 90 degrees.


That would be a turn and slip indicator or turn coordinator, a basic flight instrument.

Image
KC-135 - Passing gas and taking names!
 
User avatar
Starlionblue
Posts: 19783
Joined: Fri Feb 27, 2004 9:54 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon May 11, 2020 11:23 pm

abcgogo wrote:
Ok so got some more ideas/questions which I'd like to know why they were/are not implemented in aviation industry.

1) Why don't aircraft cockpits have a big-size "Level-Checking-Vial" like the one used in level-measurement-tools ? Those bottles with green color liquid that move based on gravity (& hence indiciate whether surface is level or not) is a good idea for aircraft in case instruments have failed or are having errors because it gives the pilot the most basic idea of whether their aircraft is levelled or not . This is especially useful at cloudy & night operations too where it is difficult/impossible to tell which way the aircraft is rolling/pitching due to spatial-disorientation. This seems to be a a quick, error-free (depends on gravity), maintenance-free, system-independent tool. To further make it useful, it can be placed on the dashboard of the cockpit right behind the centre beam (not sure what it is called) which separates the left & right forward cockpit windows and can have a LED (powered by independent battery cell like in a flashlight) so that it is easily visible even at night time. Check out this video of how the bubble in the vial moves when the bottle tilts to left/right, same way it can tell up/down pitch of the aircraft (if placed in vertical position instead of horizontal as shown in video), also see the lava-lamp video (Link-3) to understand my lighting idea.
https://youtu.be/1Hgseq9s6cw?t=588
https://youtu.be/wMJVsRDmHuo?t=155
https://youtu.be/_eA67rfLaL4?t=115



As mentioned above, a level would not tell you anything useful because the platform is constantly moving and accelerating/decelerating in various directions.

A "roll level" would still indicate level in a coordinated turn. Which is how a slip indicator works, incidentally. A "pitch level" would be affected by acceleration.


Either way, the multiple gyroscopic instruments installed, in the form of artificial horizons, already do an excellent job of telling us whether we are level or not. Think of them as levels that compensate for acceleration.

Spatial disorientation is not caused by instrument error. It is by using the instruments as a reference, that the threat spatial disorientation is managed.
Last edited by Starlionblue on Mon May 11, 2020 11:34 pm, edited 1 time in total.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
User avatar
Starlionblue
Posts: 19783
Joined: Fri Feb 27, 2004 9:54 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon May 11, 2020 11:31 pm

abcgogo wrote:
Ok so got some more ideas/questions which I'd like to know why they were/are not implemented in aviation industry.


2) Why don't pilots wear Night-Vision goggles at night just like how soldiers wear for their night-operations ? Many times we have seen in past where pilots got spatial-disorientation or confused (usually in addition to instrument problems) and ended up crashing (accident or CFIT). If they had night vision goggles they could at least be able to tell apart things like sea, mountains, trees, etc. The reason I am suggesting this is because many members here have highlighted that installing EVS/SVS/CVS systems is complex and expensive and cannot/will-not be done for older aircraft. The night vision goggle method works for pilots of all types of aircrafts be it balloons, helicopters, airplanes, etc., is cheaper than any EVS/SVS/CVS and is much more lightweight. Sure they pilots might get a bit uncomfortable initially, but with time they might get used to it just like how people who start wearing spectacles feel uncomfortable but eventually get used to it. Check out these videos showing some night vision goggles, pilots can be made to wear them with a headband (see Link-4).
https://youtu.be/d-I4KkxsqYg?t=81
https://youtu.be/dYJ9GWmDq8g?t=290
https://youtu.be/I_nSeS8qMRg?t=276
https://youtu.be/TCdTn7NAL48?t=72


In airline and business jet operations, we have multiple warning systems for terrain already, in the form of EGPWS. We also have strict navigation procedures that keep us away from the cumulus granitus.

Night vision goggles do weird things to depth perception. Everything becomes flat, which would make matters worse. The only reason the military uses night vision is because they sometimes want to operate without emitting light.

Besides as VSMUT says, spatial disorientation typically happens above cloud, so you wouldn't see the terrain anyway.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
User avatar
Starlionblue
Posts: 19783
Joined: Fri Feb 27, 2004 9:54 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Mon May 11, 2020 11:33 pm

abcgogo wrote:
Ok so got some more ideas/questions which I'd like to know why they were/are not implemented in aviation industry.


3) Why don't business jet manufacturers extend the fuselage of their aircraft ahead of the front-door to make the cockpit area more spacious so that a comfortable seat can be installed (instead of jumpseat) which can be used by flight-attendant or third-pilot ? In the long-range bizjets (Global-6000/6500/7500, G550/650/600/700, Falcon-7X/8X) there is only 1 crew rest area seat (next to the galley) and the other person (either third-pilot or flight-attendant) has to use the uncomfortable jumpseat (which is suited only for short flights that too for use by instructors/senior-pilots who are training/supervising the trainees/junior-pilots). In the old-days, airliner cockpits had 3-crew and so 3-proper seats were fitted with good space in the cockpit. Now with 2-crew airliners, that seat is replaced by a normal jumpseat & cockpit space is reduced. If the bizjet manufacturers extend the fuselage ahead of the door, they can provide a more spacious (lengthwise) cockpit area where a good 3rd seat can be installed. If manufacturers can extend the fuselage for cabin-purposes (like Challenger->CRJ; Global-6000->Global-7500; G500->G600->G700) then they can certainly do a (relatively) small extension ahead of the front door to make cockpit more spacious (lengthwise) so that a comfortable side-facing seat & storage-space can be installed. It may not be lie-flat seat due to width issues but a nice comfortable recliner seat (like regional business/first-class) is much better than the current jumpseat. Check out the jumpseat at 0:19 (on left side, it is folded) and the single crew-rest seat at 0:49 in the below video (Link-1). Check out pics of current jumpseats in bizjets (Link-2,3). Why doesn't any bizjet manufacturer take the initiative to improve crew-comfort ?
https://youtu.be/6Z6rJ1ooQgo?t=21
https://www.bombardier.com/content/dam/ ... 0.570.jpeg
http://www.jba.aero/wp-content/uploads/ ... mpseat.jpg


That would cost a lot of money. Improving crew comfort is rarely the priority for the manufacturer or the purchaser. We're are not the customer. :)
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
JayinKitsap
Posts: 2060
Joined: Sat Nov 26, 2005 9:55 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 12:13 am

Airplane safety is based on risk analysis, depending on the consequences of failure, the time between failures is adjusted. Wings breaking basically have a safety factor of 1.5 on any conceivable realistic failures, very rarely happens. One big failure in planes is maximum speed, an upset at altitude can cause a steep dive where maximum speed is exceeded. As a plane approaches mach 1, turbulence will destroy the wing unless designed for it. But planes regularly fly near mach 1. The 779 just did a period at mach 0.89 just fine. Similarly a steep dive often would require high G maneuvers to recover, can the plane survive 7G, likely but not 10G. What is the right standard?

Planes flying outside of diversion airports nearby follow ETOPS, the highest level is 330 minutes to an airfield. That takes special maintenance protocols where only one engine can be worked on in a period. Probably adds 10% to the maintenance cost, but it ensures safety. Basically it places the chance of a second failure within the 330 minutes to be 1/ 10 Billion (just recalling, may be off). This could be done on all planes but not worth the cost if the plane can divert to a nearby airport, probably 95% of narrow bodies are not ETOPS.

Safety would be improved if there were 20 exits and every passenger has a parachute, but pushing grannie out the door with a chute at 10,000 feet, 200 knots and -40F conditions might save her from a crash, but would certainly have a 90% chance of heart attach. Maybe we should do ejection seats for everyone but that would increase the cost of a 737 by about 25 million and cut the payload in half. Evacuation doors are established where it is required by test that it can be evacuated in 90 seconds with half of the exits blocked. The A380 evacuated 873 in 90 seconds in the dark. A 60 second evacuation would save more lives but the 90 seconds is a balance.


Jetblue landing with turned front wheel.
https://www.youtube.com/watch?v=epKrA8KjYvg

A landing without gear extended.
https://www.youtube.com/watch?v=Jl5n8ircdPg
 
JayinKitsap
Posts: 2060
Joined: Sat Nov 26, 2005 9:55 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 12:23 am

Moose135 wrote:
VSMUT wrote:
abcgogo wrote:
1) Why don't aircraft cockpits have a big-size "Level-Checking-Vial" like the one used in level-measurement-tools ? Those bottles with green color liquid that move based on gravity (& hence indiciate whether surface is level or not) is a good idea for aircraft in case instruments have failed or are having errors because it gives the pilot the most basic idea of whether their aircraft is levelled or not . This is especially useful at cloudy & night operations too where it is difficult/impossible to tell which way the aircraft is rolling/pitching due to spatial-disorientation. This seems to be a a quick, error-free (depends on gravity), maintenance-free, system-independent tool.


No, these are completely useless because of centrifugal forces. I could literally make a bubble level indicate straight and level while banking 90 degrees.


That would be a turn and slip indicator or turn coordinator, a basic flight instrument.

Image


Yes those are present in all aircraft. With helicopters flying in VFR conditions that degrade into IFR conditions are very, very dangerous. However, an IFR equipped helicopter is very expensive to purchase, operate and maintain. This is primarily because the rules from aircraft are brought over and they don't fit well. Possibly having a terrain radar where the ground can be seen if visuals degrade might be the most effective, that should be an instrument on all helicopters. Spatial disorientation loses all sense of what is up. As noted above, banking and other maneuvers can have accelerations exceeding multiple G's, very complex to do as an autopilot as most instruments cannot 'sense' the true gravity direction among the other accelerations.
 
User avatar
Starlionblue
Posts: 19783
Joined: Fri Feb 27, 2004 9:54 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 2:03 am

JayinKitsap wrote:
Moose135 wrote:
VSMUT wrote:

No, these are completely useless because of centrifugal forces. I could literally make a bubble level indicate straight and level while banking 90 degrees.


That would be a turn and slip indicator or turn coordinator, a basic flight instrument.

Image


Yes those are present in all aircraft. With helicopters flying in VFR conditions that degrade into IFR conditions are very, very dangerous. However, an IFR equipped helicopter is very expensive to purchase, operate and maintain. This is primarily because the rules from aircraft are brought over and they don't fit well. Possibly having a terrain radar where the ground can be seen if visuals degrade might be the most effective, that should be an instrument on all helicopters. Spatial disorientation loses all sense of what is up. As noted above, banking and other maneuvers can have accelerations exceeding multiple G's, very complex to do as an autopilot as most instruments cannot 'sense' the true gravity direction among the other accelerations.



Attitude indicators have been around since the 1920s. They are extremely reliable and have no problems with maneuvers. For obvious reasons, they are specifically designed with maneuvering in mind.

They don't need to "sense the true gravity direction". A gyroscopic attitude indicator simply stays in the same orientation as the aircraft moves around it. An intertial reference based attitude indicator is a bit more complex but, again, extremely reliable.


The problem of disorientation does not stem from the instruments. It is a human factors issue. If your senses are telling you one thing and the instruments are telling you another, trust the instruments.

If you don't have an attitude indicator, a terrain radar won't help. The first priority is to know your attitude, which is why the attitude indicator is typically the most centrally placed instrument.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
abcgogo
Topic Author
Posts: 29
Joined: Wed Mar 18, 2020 4:57 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 5:19 am

Ok I agree that the "level-checking-vial" is a bit strange idea and the gyroscope instruments members have mentioned seems to be better idea. However, these "analogue, old-school" type of instruments are going the way of the Dodo and newer aircraft cockpits are all digital (A350, 787, Global-5000/6000/7500, G550/650/500/600/700, Falcon-7X/8X) meaning they do not have these instruments (I went through pics of their cockpits and did not see any such instrument). The only cockpits where I have seen these type of instruments is on older aircraft (airliners & bizjets alike).

We have seen in past instrument problems faced by crew like in Aeroperu-603, Air-France-447, Air-Asia-8501 & maybe some others which I may have forgotten or do not know about. This makes it difficult to trust instruments in low-visibility and/or night conditions. Hence my question about the "level-checking-vials" and "night-vision-goggles" because they seem to at-least provide some basic awareness to the pilot in cloudy/dark-conditions about aircraft's position (is it levelled or not). Ok, maybe night-vision goggles won't help in low-visibility conditions (clouds, fog, etc.) but at least in night time (clear or partially clear skies) they might help (especially during takeoff/landing situations when runway visibility is most important) ? If these ideas are impractical, then why aren't regulators forcing manufacturers to include old-school analogue gyroscopes in their cockpits as a backup-measure ? There seems to be enough space in the cockpits to include at least 2 such gyroscopes (1 for each pilot). I understand they cannot force installation of EVS/SVS/CVS due to cost/complexity factors but at-least the gyroscopes can be installed I suppose ?

JayinKitsap wrote:
Airplane safety is based on risk analysis, depending on the consequences of failure, the time between failures is adjusted. Wings breaking basically have a safety factor of 1.5 on any conceivable realistic failures, very rarely happens. One big failure in planes is maximum speed, an upset at altitude can cause a steep dive where maximum speed is exceeded. As a plane approaches mach 1, turbulence will destroy the wing unless designed for it. But planes regularly fly near mach 1. The 779 just did a period at mach 0.89 just fine. Similarly a steep dive often would require high G maneuvers to recover, can the plane survive 7G, likely but not 10G. What is the right standard?

Planes flying outside of diversion airports nearby follow ETOPS, the highest level is 330 minutes to an airfield. That takes special maintenance protocols where only one engine can be worked on in a period. Probably adds 10% to the maintenance cost, but it ensures safety. Basically it places the chance of a second failure within the 330 minutes to be 1/ 10 Billion (just recalling, may be off). This could be done on all planes but not worth the cost if the plane can divert to a nearby airport, probably 95% of narrow bodies are not ETOPS.

Safety would be improved if there were 20 exits and every passenger has a parachute, but pushing grannie out the door with a chute at 10,000 feet, 200 knots and -40F conditions might save her from a crash, but would certainly have a 90% chance of heart attach. Maybe we should do ejection seats for everyone but that would increase the cost of a 737 by about 25 million and cut the payload in half. Evacuation doors are established where it is required by test that it can be evacuated in 90 seconds with half of the exits blocked. The A380 evacuated 873 in 90 seconds in the dark. A 60 second evacuation would save more lives but the 90 seconds is a balance.


Jetblue landing with turned front wheel.
https://www.youtube.com/watch?v=epKrA8KjYvg

A landing without gear extended.
https://www.youtube.com/watch?v=Jl5n8ircdPg


I had mentioned in my previous posts on this thread that

1) I meant about gear collapsing upon landing (because aircraft is heavier than MLW) which could break into the wings & fuel tanks thereby starting a huge fireball. Planned gear collapse/malfunction landings do not count because the gear's status was known before landing (either down or not down). Other members addressed those questions though.

2) Regarding evacuations I had in mind "getting people on the plane" (like evacuations done by Air-India and El-Al in conflict-zones) for which airstairs might be necessary not the usual "getting people off the plane" (for which the exit doors & emergency slides are more than enough (as you too have pointed out).
 
VSMUT
Posts: 3966
Joined: Mon Aug 08, 2016 11:40 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 6:26 am

abcgogo wrote:
Ok I agree that the "level-checking-vial" is a bit strange idea and the gyroscope instruments members have mentioned seems to be better idea. However, these "analogue, old-school" type of instruments are going the way of the Dodo and newer aircraft cockpits are all digital (A350, 787, Global-5000/6000/7500, G550/650/500/600/700, Falcon-7X/8X) meaning they do not have these instruments (I went through pics of their cockpits and did not see any such instrument). The only cockpits where I have seen these type of instruments is on older aircraft (airliners & bizjets alike).


The gyros are still there. The difference is, now it displays the data on a screen rather than a ball inside a gauge. Most aircraft should have 3 separate gyros. The advantage is that if one gyro and/or screen fails, we can still pull up the information from one of the other gyros or display it on a different screen.
 
User avatar
Starlionblue
Posts: 19783
Joined: Fri Feb 27, 2004 9:54 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 7:23 am

VSMUT wrote:
abcgogo wrote:
Ok I agree that the "level-checking-vial" is a bit strange idea and the gyroscope instruments members have mentioned seems to be better idea. However, these "analogue, old-school" type of instruments are going the way of the Dodo and newer aircraft cockpits are all digital (A350, 787, Global-5000/6000/7500, G550/650/500/600/700, Falcon-7X/8X) meaning they do not have these instruments (I went through pics of their cockpits and did not see any such instrument). The only cockpits where I have seen these type of instruments is on older aircraft (airliners & bizjets alike).


The gyros are still there. The difference is, now it displays the data on a screen rather than a ball inside a gauge. Most aircraft should have 3 separate gyros. The advantage is that if one gyro and/or screen fails, we can still pull up the information from one of the other gyros or display it on a different screen.


I’ll add that modern display based attitude indicator and solid state gyros are far more reliable than their mechanical counterparts.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
User avatar
Starlionblue
Posts: 19783
Joined: Fri Feb 27, 2004 9:54 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 7:25 am

abcgogo wrote:
Ok I agree that the "level-checking-vial" is a bit strange idea and the gyroscope instruments members have mentioned seems to be better idea. However, these "analogue, old-school" type of instruments are going the way of the Dodo and newer aircraft cockpits are all digital (A350, 787, Global-5000/6000/7500, G550/650/500/600/700, Falcon-7X/8X) meaning they do not have these instruments (I went through pics of their cockpits and did not see any such instrument). The only cockpits where I have seen these type of instruments is on older aircraft (airliners & bizjets alike).

We have seen in past instrument problems faced by crew like in Aeroperu-603, Air-France-447, Air-Asia-8501 & maybe some others which I may have forgotten or do not know about. This makes it difficult to trust instruments in low-visibility and/or night conditions. Hence my question about the "level-checking-vials" and "night-vision-goggles" because they seem to at-least provide some basic awareness to the pilot in cloudy/dark-conditions about aircraft's position (is it levelled or not). Ok, maybe night-vision goggles won't help in low-visibility conditions (clouds, fog, etc.) but at least in night time (clear or partially clear skies) they might help (especially during takeoff/landing situations when runway visibility is most important) ? If these ideas are impractical, then why aren't regulators forcing manufacturers to include old-school analogue gyroscopes in their cockpits as a backup-measure ? There seems to be enough space in the cockpits to include at least 2 such gyroscopes (1 for each pilot). I understand they cannot force installation of EVS/SVS/CVS due to cost/complexity factors but at-least the gyroscopes can be installed I suppose ?

JayinKitsap wrote:
Airplane safety is based on risk analysis, depending on the consequences of failure, the time between failures is adjusted. Wings breaking basically have a safety factor of 1.5 on any conceivable realistic failures, very rarely happens. One big failure in planes is maximum speed, an upset at altitude can cause a steep dive where maximum speed is exceeded. As a plane approaches mach 1, turbulence will destroy the wing unless designed for it. But planes regularly fly near mach 1. The 779 just did a period at mach 0.89 just fine. Similarly a steep dive often would require high G maneuvers to recover, can the plane survive 7G, likely but not 10G. What is the right standard?

Planes flying outside of diversion airports nearby follow ETOPS, the highest level is 330 minutes to an airfield. That takes special maintenance protocols where only one engine can be worked on in a period. Probably adds 10% to the maintenance cost, but it ensures safety. Basically it places the chance of a second failure within the 330 minutes to be 1/ 10 Billion (just recalling, may be off). This could be done on all planes but not worth the cost if the plane can divert to a nearby airport, probably 95% of narrow bodies are not ETOPS.

Safety would be improved if there were 20 exits and every passenger has a parachute, but pushing grannie out the door with a chute at 10,000 feet, 200 knots and -40F conditions might save her from a crash, but would certainly have a 90% chance of heart attach. Maybe we should do ejection seats for everyone but that would increase the cost of a 737 by about 25 million and cut the payload in half. Evacuation doors are established where it is required by test that it can be evacuated in 90 seconds with half of the exits blocked. The A380 evacuated 873 in 90 seconds in the dark. A 60 second evacuation would save more lives but the 90 seconds is a balance.


Jetblue landing with turned front wheel.
https://www.youtube.com/watch?v=epKrA8KjYvg

A landing without gear extended.
https://www.youtube.com/watch?v=Jl5n8ircdPg


I had mentioned in my previous posts on this thread that

1) I meant about gear collapsing upon landing (because aircraft is heavier than MLW) which could break into the wings & fuel tanks thereby starting a huge fireball. Planned gear collapse/malfunction landings do not count because the gear's status was known before landing (either down or not down). Other members addressed those questions though.

2) Regarding evacuations I had in mind "getting people on the plane" (like evacuations done by Air-India and El-Al in conflict-zones) for which airstairs might be necessary not the usual "getting people off the plane" (for which the exit doors & emergency slides are more than enough (as you too have pointed out).


Again, conflict zones and such are once in a lifetime events. You don’t want to carry around all that extra weight just in case.

If you’re in a hurry or there are no stairs available, just use the slides.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
SAAFNAV
Posts: 598
Joined: Wed Mar 17, 2010 5:41 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 7:58 am

abcgogo wrote:
Ok so got some more ideas/questions which I'd like to know why they were/are not implemented in aviation industry.

1) Why don't aircraft cockpits have a big-size "Level-Checking-Vial" like the one used in level-measurement-tools ? Those bottles with green color liquid that move based on gravity (& hence indiciate whether surface is level or not) is a good idea for aircraft in case instruments have failed or are having errors because it gives the pilot the most basic idea of whether their aircraft is levelled or not . This is especially useful at cloudy & night operations too where it is difficult/impossible to tell which way the aircraft is rolling/pitching due to spatial-disorientation. This seems to be a a quick, error-free (depends on gravity), maintenance-free, system-independent tool. To further make it useful, it can be placed on the dashboard of the cockpit right behind the centre beam (not sure what it is called) which separates the left & right forward cockpit windows and can have a LED (powered by independent battery cell like in a flashlight) so that it is easily visible even at night time. Check out this video of how the bubble in the vial moves when the bottle tilts to left/right, same way it can tell up/down pitch of the aircraft (if placed in vertical position instead of horizontal as shown in video), also see the lava-lamp video (Link-3) to understand my lighting idea.
https://youtu.be/1Hgseq9s6cw?t=588
https://youtu.be/wMJVsRDmHuo?t=155
https://youtu.be/_eA67rfLaL4?t=115

2) Why don't pilots wear Night-Vision goggles at night just like how soldiers wear for their night-operations ? Many times we have seen in past where pilots got spatial-disorientation or confused (usually in addition to instrument problems) and ended up crashing (accident or CFIT). If they had night vision goggles they could at least be able to tell apart things like sea, mountains, trees, etc. The reason I am suggesting this is because many members here have highlighted that installing EVS/SVS/CVS systems is complex and expensive and cannot/will-not be done for older aircraft. The night vision goggle method works for pilots of all types of aircrafts be it balloons, helicopters, airplanes, etc., is cheaper than any EVS/SVS/CVS and is much more lightweight. Sure they pilots might get a bit uncomfortable initially, but with time they might get used to it just like how people who start wearing spectacles feel uncomfortable but eventually get used to it. Check out these videos showing some night vision goggles, pilots can be made to wear them with a headband (see Link-4).
https://youtu.be/d-I4KkxsqYg?t=81
https://youtu.be/dYJ9GWmDq8g?t=290
https://youtu.be/I_nSeS8qMRg?t=276
https://youtu.be/TCdTn7NAL48?t=72

3) Why don't business jet manufacturers extend the fuselage of their aircraft ahead of the front-door to make the cockpit area more spacious so that a comfortable seat can be installed (instead of jumpseat) which can be used by flight-attendant or third-pilot ? In the long-range bizjets (Global-6000/6500/7500, G550/650/600/700, Falcon-7X/8X) there is only 1 crew rest area seat (next to the galley) and the other person (either third-pilot or flight-attendant) has to use the uncomfortable jumpseat (which is suited only for short flights that too for use by instructors/senior-pilots who are training/supervising the trainees/junior-pilots). In the old-days, airliner cockpits had 3-crew and so 3-proper seats were fitted with good space in the cockpit. Now with 2-crew airliners, that seat is replaced by a normal jumpseat & cockpit space is reduced. If the bizjet manufacturers extend the fuselage ahead of the door, they can provide a more spacious (lengthwise) cockpit area where a good 3rd seat can be installed. If manufacturers can extend the fuselage for cabin-purposes (like Challenger->CRJ; Global-6000->Global-7500; G500->G600->G700) then they can certainly do a (relatively) small extension ahead of the front door to make cockpit more spacious (lengthwise) so that a comfortable side-facing seat & storage-space can be installed. It may not be lie-flat seat due to width issues but a nice comfortable recliner seat (like regional business/first-class) is much better than the current jumpseat. Check out the jumpseat at 0:19 (on left side, it is folded) and the single crew-rest seat at 0:49 in the below video (Link-1). Check out pics of current jumpseats in bizjets (Link-2,3). Why doesn't any bizjet manufacturer take the initiative to improve crew-comfort ?
https://youtu.be/6Z6rJ1ooQgo?t=21
https://www.bombardier.com/content/dam/ ... 0.570.jpeg
http://www.jba.aero/wp-content/uploads/ ... mpseat.jpg


My thought is a bit of weird one, but maybe you can try it: Why don't you first try to understand aviation, before you picket to change rules?
There are various means to obtain the above information, and just because you don't see a C172-type instrument in a new airliner, doesn't mean the underlying principles aren't used.

It is actually because our CAA is filled up by people who have never seen an aircraft, that we have issues like we do in our country.
L-382 Loadmaster; ex C-130B Navigator
 
mmo
Posts: 1963
Joined: Thu Apr 18, 2013 3:04 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 10:39 am

To the OP, I appreciate your enthusiasm. However, in order to have some grasp of what you are proposing as "improvements", you might want to get some more basic knowledge of airline operations and how the current generation instruments are integrated into the cockpit.

For example, you have tried to push NVG as a solution for a problem that doesn't really exist. You are trying to justify your position by reverting to more and more useless proposals. For example, your last EVS proposal was for "clear or partially clear skies". Well, when was the last commercial aircraft accident in those situations? I can't remember. There isn't a problem in those situations. NVGs don't work well in restricted visibility. If you look at the last series fo CFIT during an approach, they were accidents, in my opinion, which would have occurred if you put every available sensor into the cockpit. The pilots busted minimums and I hate to say it, there will always be pilots who do that.

You have mentioned AF 447 several times. Boeing and Airbus have a checklist to handle "Unreliable Airspeed". It is a very basic checklist but it works. That was never referenced in that situation. The problem wasn't the lack of sensors it was the lack of knowledge, in my opinion.
If we weren't all crazy we'd all go insane!
 
JayinKitsap
Posts: 2060
Joined: Sat Nov 26, 2005 9:55 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 1:08 pm

Starlionblue wrote:
JayinKitsap wrote:
Moose135 wrote:

That would be a turn and slip indicator or turn coordinator, a basic flight instrument.

Image


Yes those are present in all aircraft. With helicopters flying in VFR conditions that degrade into IFR conditions are very, very dangerous. However, an IFR equipped helicopter is very expensive to purchase, operate and maintain. This is primarily because the rules from aircraft are brought over and they don't fit well. Possibly having a terrain radar where the ground can be seen if visuals degrade might be the most effective, that should be an instrument on all helicopters. Spatial disorientation loses all sense of what is up. As noted above, banking and other maneuvers can have accelerations exceeding multiple G's, very complex to do as an autopilot as most instruments cannot 'sense' the true gravity direction among the other accelerations.



Attitude indicators have been around since the 1920s. They are extremely reliable and have no problems with maneuvers. For obvious reasons, they are specifically designed with maneuvering in mind.

They don't need to "sense the true gravity direction". A gyroscopic attitude indicator simply stays in the same orientation as the aircraft moves around it. An intertial reference based attitude indicator is a bit more complex but, again, extremely reliable.


The problem of disorientation does not stem from the instruments. It is a human factors issue. If your senses are telling you one thing and the instruments are telling you another, trust the instruments.

If you don't have an attitude indicator, a terrain radar won't help. The first priority is to know your attitude, which is why the attitude indicator is typically the most centrally placed instrument.


I alway appreciate your experience and knowledge of aviation, I can tell it came from a career in it. My career is designing buildings including a lot of Navy projects, so just a geek around aviation. Yes gyro attitude indicators have been around forever. I recall reading something that a real compass and some other critical gauges were still required separate from the CRT's in case they go down and a last resort is needed, sort of back to canvas bi planes.

I was bringing up the IFR rules for helicopters having problems like Kobe's crash occur far too frequently, The IRF rules are prudent for aircraft, but as helicopters fly to lots of places not airports different rules are needed. It could be some simple additions to the VFR instrumentation, but less than what is currently identified for IFR in helicopters. I was shocked to read how few helo IFR instructors have flow more than a dozen hours in real IRF conditions. Spatial Disorientation is the cause of far too many rotocraft.

https://www.verticalmag.com/features/he ... nt-safety/
 
User avatar
Starlionblue
Posts: 19783
Joined: Fri Feb 27, 2004 9:54 pm

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 1:22 pm

JayinKitsap wrote:
Starlionblue wrote:
JayinKitsap wrote:

Yes those are present in all aircraft. With helicopters flying in VFR conditions that degrade into IFR conditions are very, very dangerous. However, an IFR equipped helicopter is very expensive to purchase, operate and maintain. This is primarily because the rules from aircraft are brought over and they don't fit well. Possibly having a terrain radar where the ground can be seen if visuals degrade might be the most effective, that should be an instrument on all helicopters. Spatial disorientation loses all sense of what is up. As noted above, banking and other maneuvers can have accelerations exceeding multiple G's, very complex to do as an autopilot as most instruments cannot 'sense' the true gravity direction among the other accelerations.



Attitude indicators have been around since the 1920s. They are extremely reliable and have no problems with maneuvers. For obvious reasons, they are specifically designed with maneuvering in mind.

They don't need to "sense the true gravity direction". A gyroscopic attitude indicator simply stays in the same orientation as the aircraft moves around it. An intertial reference based attitude indicator is a bit more complex but, again, extremely reliable.


The problem of disorientation does not stem from the instruments. It is a human factors issue. If your senses are telling you one thing and the instruments are telling you another, trust the instruments.

If you don't have an attitude indicator, a terrain radar won't help. The first priority is to know your attitude, which is why the attitude indicator is typically the most centrally placed instrument.


I alway appreciate your experience and knowledge of aviation, I can tell it came from a career in it. My career is designing buildings including a lot of Navy projects, so just a geek around aviation. Yes gyro attitude indicators have been around forever. I recall reading something that a real compass and some other critical gauges were still required separate from the CRT's in case they go down and a last resort is needed, sort of back to canvas bi planes.

I was bringing up the IFR rules for helicopters having problems like Kobe's crash occur far too frequently, The IRF rules are prudent for aircraft, but as helicopters fly to lots of places not airports different rules are needed. It could be some simple additions to the VFR instrumentation, but less than what is currently identified for IFR in helicopters. I was shocked to read how few helo IFR instructors have flow more than a dozen hours in real IRF conditions. Spatial Disorientation is the cause of far too many rotocraft.

https://www.verticalmag.com/features/he ... nt-safety/


The Kobe Bryant crash has not been conclusively investigated yet, but most indications was that it was CFIT due to disorientation. Not an instrument problem.

More IFR training and awareness would probably save a lot of lives, in both fixed and rotary wing.
"There are no stupid questions, but there are a lot of inquisitive idiots." - John Ringo
 
JayinKitsap
Posts: 2060
Joined: Sat Nov 26, 2005 9:55 am

Re: Why do aviation safety agencies overlook obvious safety deficiencies ?

Tue May 12, 2020 1:25 pm

abcgogo wrote:
JayinKitsap wrote:
Airplane safety is based on risk analysis, depending on the consequences of failure, the time between failures is adjusted. Wings breaking basically have a safety factor of 1.5 on any conceivable realistic failures, very rarely happens. One big failure in planes is maximum speed, an upset at altitude can cause a steep dive where maximum speed is exceeded. As a plane approaches mach 1, turbulence will destroy the wing unless designed for it. But planes regularly fly near mach 1. The 779 just did a period at mach 0.89 just fine. Similarly a steep dive often would require high G maneuvers to recover, can the plane survive 7G, likely but not 10G. What is the right standard?

Planes flying outside of diversion airports nearby follow ETOPS, the highest level is 330 minutes to an airfield. That takes special maintenance protocols where only one engine can be worked on in a period. Probably adds 10% to the maintenance cost, but it ensures safety. Basically it places the chance of a second failure within the 330 minutes to be 1/ 10 Billion (just recalling, may be off). This could be done on all planes but not worth the cost if the plane can divert to a nearby airport, probably 95% of narrow bodies are not ETOPS.

Safety would be improved if there were 20 exits and every passenger has a parachute, but pushing grannie out the door with a chute at 10,000 feet, 200 knots and -40F conditions might save her from a crash, but would certainly have a 90% chance of heart attach. Maybe we should do ejection seats for everyone but that would increase the cost of a 737 by about 25 million and cut the payload in half. Evacuation doors are established where it is required by test that it can be evacuated in 90 seconds with half of the exits blocked. The A380 evacuated 873 in 90 seconds in the dark. A 60 second evacuation would save more lives but the 90 seconds is a balance.


Jetblue landing with turned front wheel.
https://www.youtube.com/watch?v=epKrA8KjYvg

A landing without gear extended.
https://www.youtube.com/watch?v=Jl5n8ircdPg


I had mentioned in my previous posts on this thread that

1) I meant about gear collapsing upon landing (because aircraft is heavier than MLW) which could break into the wings & fuel tanks thereby starting a huge fireball. Planned gear collapse/malfunction landings do not count because the gear's status was known before landing (either down or not down). Other members addressed those questions though.

2) Regarding evacuations I had in mind "getting people on the plane" (like evacuations done by Air-India and El-Al in conflict-zones) for which airstairs might be necessary not the usual "getting people off the plane" (for which the exit doors & emergency slides are more than enough (as you too have pointed out).


1) Early in the thread you were quite excited about bursting tires, well if a nose gear turned 90 grinding all the tires up, then about 8" of the gear leg indicated that planes can land with burst tires, if the 2nd tire of the pair can't carry it, the metal of the gear can. Landing gear collapses, but they are surprisingly rare.

2) Boarding a plane in a conflict zone is best with a real airstair not some ricketety built in stairway. that replaces a slide which is far safer. If bullets are flying any one thru the hull will kill the pressurization. If one cannot get an airstair to the plane because of bullets flying, one needs a security force as there is probably FOD everywhere on the runway. American Airlines flies like 4,000 flights a day, they may have been hit by stray bullets flying over Baltimore but unlikely at any airport they fly.

If the air stair is needed, shouldn't the hull be more resistant. The KC-46 has a thicker skin than other 767's to stop basic rifle rounds, it was like a 1/2 mm.

Who is online

Users browsing this forum: Flow2706 and 47 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos