frmrCapCadet wrote:

My point, a small independent GPS showing ground speed, heading, location, elevations (for aviation) seems to me essential for any sort of transportation.

For navigational purposes, I would agree, and the Max has it. But for airplane handling? No, because GPS give ground speed, and airplanes fly with ground speed. The problem is wind... That's why Airbus rely on BUSS when the ADRs get drunk, and use AOA instead of airspeed.

amishfarmer wrote:

Can anyone enlighten me on this pertaining to the 737? If this has been addressed already sorry for repeating it.

737NGs and MAXs, just change ADC to ADR, and you got a similar way to deal with it when in the air. The question here is, did they manage to isolate the faulty ADR or not?

Zeke wrote:

I could believe Airbus training the JT crew for their A330s, however not for the 737s.

The training is under Airbus partnership with Lion Air. Even the pilot recruitment requirements are "set by Airbus"...
This did cause a bit of a fuss early 2017 when we had fresh CPLMEIRs being rejected by Lion after the Airbus side of the partnership started to get Lion to accept their recruitment new standards. However, this is no guarantee that you'd still get bad apples coming in.

salttee wrote:

No, ADS-B is not exclusively GPS-derived.

In Indonesia, a GPS-based ADS-B is now mandatory in RVSM airspace since end of May 2017. Non GPS-Based ADS-B has caused enough problems over here by transmitting erroneous/inaccurate positions with defeats the purpose. I've seen non GPS-based ADS-B equipped aircraft transmitting ADSB positions that are more than 0.5NM away. We're better off getting them switched off when it's not GPS-based.

salttee wrote:

Is it true that there are many ADS-B features that are not used by all aircraft or all customers?

True. Unfortunately, I cannot discuss them in the open like this without checking my NDA on the subject. However, I can say that freely available literature is out there. You can get a LOT of stuff from ADS-B, provided it's done correctly.

sccutler wrote:

A poster above seems to believe ADS-B out data somehow includes pitot/static-derived data; it does not. The location, speed and altitude information transmitted by ADS-B units (whether 1090ES or the 978UAT) is exclusively GPS-derived.

The basic data is. When not GPS based, those basic data will be IRS or FMC based... which can be visually toxic when displayed in a crowded aispace. However the pitot-static derived data exist and is transmitted, provided the aircraft has that version. 737Max ADSB, at least the ones that fly here, has them.

osiris30 wrote:

With the correct software you could calculate a lot of data off engine performance for example These software changes add no weight and little long term cost.

Good news for you, A350 has that, in the extremely unlikely event your ISIS gets screwed up too. However, it has it's limitations. I have yet to read the detailed literature on it though. Am not sure if this is standard or an option.

mandala499 wrote:

- Initial FDR analysis will take 1-2 weeks.
- CVR pings are reported to be "in and out" through this afternoon's search dives.

One thing puzzles me. This plane was produced this year 2018. Type certificate is little older. Still:

The memory chips for the FDR and CVR seem to be contained in two different crash and fire resistant units. Each with its own pinger with 30 days pinger battery.

How can that be so? We are writing 2018 today. Are there other plane types, which are produced today with similar recorder configuration?

I refuse to accept that 737MAX flies with the same tape recorders as the 737-200 fifty years ago.

prebennorholm wrote:

mandala499 wrote:

- Initial FDR analysis will take 1-2 weeks.
- CVR pings are reported to be "in and out" through this afternoon's search dives.

One thing puzzles me. This plane was produced this year 2018. Type certificate is little older. Still:

The memory chips for the FDR and CVR seem to be contained in two different crash and fire resistant units. Each with its own pinger with 30 days pinger battery.

How can that be so? We are writing 2018 today. Are there other plane types, which are produced today with similar recorder configuration?

I refuse to accept that 737MAX flies with the same tape recorders as the 737-200 fifty years ago.

Where are you seeing anything about a tape FDR/CVR?

osiris30 wrote:

Starlionblue wrote:

osiris30 wrote:

Not arguing with you as the physics make perfect sense but am curious why it seems to go wrong so often? (relatively speaking). In aviation we are always trying to improve from best practices. Given today's tech we should be able to better safeguard planes. Even an auto pitch and power button. Something.

Because, as mentioned by INFINITI329, pitot damage can be hard to spot. If a bunch of hornets have decided this would be a neat nesting location you won't see them on a walkaround. And that's one of the reasons some kind of valid airspeed check is done on take-off in everything from a light piston to an airliner.

Pitots by their nature have to be tubes pointed into the wind, and there's crap flying around that can lodge in them, plus icing. If you think about it, the pitot-static system feels a bit agricultural in concept compared to all the solid state tech wizardry we have on board. It is century old tech. Way upthread is a reference to a project developing airspeed measurement without the need for a pitot tube, through some sort of solid state sensing. That would be massively useful.

An auto pitch and power function is an idea. However this would have to be pilot initiated, and if the pilots are going to do something they might as well set pitch and power themselves.

Speaking of automatic backup speed measurement, aircraft like the (newer) 320 and 330 have backup speed scale. If the ADIRUs disagree, the speed scale will revert from pitot-static to a pure AoA scale taken from the AoA vanes. You might not know your exact speed but you know that your AoA is "safe". A great feature. On even newer aircraft like the 350, if the ADIRUs are considered unreliable, the system automatically switches to ISIS data, and if even that is unreliable the system switches to the engine air data system. Yes, engines have their own air data systems.

See those systems are what I am talking about The continuous improvement of systems. As you know that is why aviation is so safe today. I don't accept (nor do I think we should accept) that something is too uncommon to try and fiz provided the fix is reasonable.

With the correct software you could calculate a lot of data off engine performance for example These software changes add no weight and little long term cost.

Not say this is an end of the world thing but I do think we can do better. TY for the constructive discussion.

Agreed; however, this extra software on many modern aircraft would require some heftier processing power (hardware), but with transistors being smaller these days, there might even be a weight savings compared to the "current" 1988 A320 or 1997 737NG/MAX avionics.

For instance, not sure the old Intel 80186's and and Motorola 68000's on the A320 could handle it alone, and the ancient AM29f CPU's on the brand new 763 freighters would certainly have a fit.

estorilm wrote:

SO many crashes and incidents lately are in some way related to unreliable airspeed, pitot static failures, etc..

MANY (if not all) have significant issues and failures leading to the events, but aviation safety has always been about removing that "link" in the chain which causes the highest number of failure events to continue towards tragedy.

With this in mind (and I was just having a conversation with someone about this the other day) I can easily see AoA sensors and some sort of integration into PFD to provide a SIMPLE visual method for safe flight in the event of any of these failures to become a top priority and requirement for future / new aircraft. The pile of incidents that would be directly impacted and potentially altered by this technology is growing quickly. Reminds me of TCAS and GPWS incidents before those systems were installed - and look how much safer aviation has become in the wake of those technologies.

Absolutely spot on! There has been too many fatal accidents related to airspeed. On top of AoA, ground doppler can be a cue - it is off by wind speed but is a help.

I'll just add: Both manufacturers need to address this in the aircraft firmware. The computer systems should be able to recognize unreliable airspeed and altitude. Inertial disagreement with airspeed changes, radar altimeter vs. barometric, etc.. can be cues of a problem. Both warning that airspeed is unreliable AND stopping the frequent, contradictory, warnings would help reduce the confusion.

estorilm wrote:

I think it needs to be looked at as a requirement for new model certifications.

Did the 737MAX get a new certificate, or is it still legacy?

I still can't believe when the problem already occured on the last 4 flights and yet the plane still has a green light to be operational. It makes me wonder how the airline in Indonesia as a whole dealing with maintenance issue and CRM pilot training. My car's engine didnt sound right last week and I immediately stop using it and have tech made repair before I could use it again.

gia777 wrote:

I still can't believe when the problem already occured on the last 4 flights and yet the plane still has a green light to be operational. It makes me wonder how the airline in Indonesia as a whole dealing with maintenance issue and CRM pilot training. My car's engine didnt sound right last week and I immediately stop using it and have tech made repair before I could use it again.

The FDR indicated a problem for the last four flights. We don't know if the pilots on the previous flights reported the problem or even noticed the issue inflight yet.

Correct.
Knowing whether it was reported, and whether any other maintenance was conducted on the additional two preceding flights is important.

mandala499 wrote:

sccutler wrote:

A poster above seems to believe ADS-B out data somehow includes pitot/static-derived data; it does not. The location, speed and altitude information transmitted by ADS-B units (whether 1090ES or the 978UAT) is exclusively GPS-derived.

The basic data is. When not GPS based, those basic data will be IRS or FMC based... which can be visually toxic when displayed in a crowded aispace. However the pitot-static derived data exist and is transmitted, provided the aircraft has that version. 737Max ADSB, at least the ones that fly here, has them.

The data block from ADS-B on airliners includes the GPS position, speed, altitude etc, the mode control panel information, and indicated air data. The indicated air data is used in places like LHR and DXB where the NATS etc send airlines monthly reports on speed compliance on final approach. The read the aircraft position and speed and score that against the published requirements. Airlines are ranked against each other.

In Europe they also use the ADS-B mode control panel (MCP) data against the ATC clearance. For example if ATC cleared a climb to FL350 and pilots set FL330 in the MCP, it appears on the radar with an alert which is normally promptly followed by another instruction by ATC to FL350.

The basic data block on a GA aircraft is far less populated.

Aprently the the Pilots had reported the problem with caculating air speed issue on previous flight and the maintenance crew did nothing about it. See article below for full details.

Quote from NPR article:
“Lion Air reportedly knew that the plane — a brand-new Boeing 737 MAX 8, which the low-cost carrier had been using for only a few months — had malfunctioned on its second-to-last flight. That flight on Oct. 28 was just hours before the fatal flight the next morning.

Indonesian Airliner Crashes With 189 Aboard, Minutes After Takeoff
ASIA
Indonesian Airliner Crashes With 189 Aboard, Minutes After Takeoff
On Oct. 31, a Lion Air spokesman told Bloomberg that pilots had reported an issue calculating airspeed during that Oct. 28 flight. The spokesman said the instruments were examined by a maintenance crew between the penultimate and final flights. Reuters spoke to a pilot and an airport authority official who confirmed that a problem with the plane had been indicated in a radio alert.”

https://www.npr.org/2018/11/05/66431110 ... -data-show

sonic67 wrote:

Aprently the the Pilots had reported the problem with caculating air speed issue on previous flight and the maintenance crew did nothing about it. See article below for full details.

Quote from NPR article:
“Lion Air reportedly knew that the plane — a brand-new Boeing 737 MAX 8, which the low-cost carrier had been using for only a few months — had malfunctioned on its second-to-last flight. That flight on Oct. 28 was just hours before the fatal flight the next morning.

Indonesian Airliner Crashes With 189 Aboard, Minutes After Takeoff
ASIA
Indonesian Airliner Crashes With 189 Aboard, Minutes After Takeoff
On Oct. 31, a Lion Air spokesman told Bloomberg that pilots had reported an issue calculating airspeed during that Oct. 28 flight. The spokesman said the instruments were examined by a maintenance crew between the penultimate and final flights. Reuters spoke to a pilot and an airport authority official who confirmed that a problem with the plane had been indicated in a radio alert.”

https://www.npr.org/2018/11/05/66431110 ... -data-show

The maintenance log reposted several times here does indicate they flushed the tubes. This would be doing something, just clearly not the corrective action needed to resolve the issue.

sonic67 wrote:

Aprently the the Pilots had reported the problem with caculating air speed issue on previous flight and the maintenance crew did nothing about it. See article below for full details.

Can you point out where in the article that said the maintenance crew did nothing about the problems? I can't seem to find that part...

MatthewDB wrote:

Absolutely spot on! There has been too many fatal accidents related to airspeed. On top of AoA, ground doppler can be a cue - it is off by wind speed but is a help.

I'll just add: Both manufacturers need to address this in the aircraft firmware. The computer systems should be able to recognize unreliable airspeed and altitude.

Unreliable or loss of airspeed has been happening since planes started flying with pitot tubes. The computer systems in modern planes do recognise it, disable the autopilot and alert the crew to the condition.

While not yet knowing what happened here, in other cases what has happened is that crew are not following SOP to deal with and recover from the situation. There are arguments that modern crew are too reliant on automation and don't have enough basic flying skills to fly the plane manually when errors occur. When that does happen, a situation from which it is relatively simple to recover, quickly escalates to the overloaded situation that turns into a disaster.

Side note:

Just watched a news report on the crash and it showed an AirAsia A320..... ??!

1989worstyear wrote:

osiris30 wrote:

Starlionblue wrote:

Because, as mentioned by INFINITI329, pitot damage can be hard to spot. If a bunch of hornets have decided this would be a neat nesting location you won't see them on a walkaround. And that's one of the reasons some kind of valid airspeed check is done on take-off in everything from a light piston to an airliner.

Pitots by their nature have to be tubes pointed into the wind, and there's crap flying around that can lodge in them, plus icing. If you think about it, the pitot-static system feels a bit agricultural in concept compared to all the solid state tech wizardry we have on board. It is century old tech. Way upthread is a reference to a project developing airspeed measurement without the need for a pitot tube, through some sort of solid state sensing. That would be massively useful.

An auto pitch and power function is an idea. However this would have to be pilot initiated, and if the pilots are going to do something they might as well set pitch and power themselves.

Speaking of automatic backup speed measurement, aircraft like the (newer) 320 and 330 have backup speed scale. If the ADIRUs disagree, the speed scale will revert from pitot-static to a pure AoA scale taken from the AoA vanes. You might not know your exact speed but you know that your AoA is "safe". A great feature. On even newer aircraft like the 350, if the ADIRUs are considered unreliable, the system automatically switches to ISIS data, and if even that is unreliable the system switches to the engine air data system. Yes, engines have their own air data systems.

See those systems are what I am talking about The continuous improvement of systems. As you know that is why aviation is so safe today. I don't accept (nor do I think we should accept) that something is too uncommon to try and fiz provided the fix is reasonable.

With the correct software you could calculate a lot of data off engine performance for example These software changes add no weight and little long term cost.

Not say this is an end of the world thing but I do think we can do better. TY for the constructive discussion.

Agreed; however, this extra software on many modern aircraft would require some heftier processing power (hardware), but with transistors being smaller these days, there might even be a weight savings compared to the "current" 1988 A320 or 1997 737NG/MAX avionics.

For instance, not sure the old Intel 80186's and and Motorola 68000's on the A320 could handle it alone, and the ancient AM29f CPU's on the brand new 763 freighters would certainly have a fit.

Well the 186s and 68ks both have off the shelf upgrades that are instruction level compatible that could be used. the 29k are trickier for sure but I am willing to bet amd would be happy to fab some on a newer process at high clock speeds if Boeing was paying.

Erebus wrote:

Amiga500 wrote:

Or deploying (in a similar manner to the RAT) a drag chute and measure the load on the cable. Both could be deployed and retracted from the cockpit and provide vital sanity checks to PS data.

That's an interesting concept. Can the RAT itself be modified in any way to derive airpseed data as a backup?

It certainly could - wouldn't be exact - same as the other approaches I have proposed, but then, we aren't looking or needing exact.


One issue would be high speed deployment, if you look at AF447, then the pilots might believe they are in a high Mach environment, where deployment in itself might be considered dangerous. Also, measuring airspeed from propellors at high Mach is very challenging due to supersonic effects.


**However**, it has gave me another thought. We don't necessarily need to even know airspeed, we need to know actual angle of attack. So have a hung vane on the side of the aircraft (similar to the guide vane you see at the tail of a wind turbine or anemometer, example below) - looking at it now - it probably should be a standard continuous feedback instrument and not merely warning of approaching stall via the shaker/audible alarm.

So the pilots have attitude indicator, they have throttle and they have real angle of attack. That should be all they need to fly the plane safely straight and level until they can get on top of the problem(s).

Amiga500 wrote:

Erebus wrote:

Amiga500 wrote:

**However**, it has gave me another thought. We don't necessarily need to even know airspeed, we need to know actual angle of attack. So have a hung vane on the side of the aircraft (similar to the guide vane you see at the tail of a wind turbine or anemometer, example below) - looking at it now - it probably should be a standard continuous feedback instrument and not merely warning of approaching stall via the shaker/audible alarm.

You mean this thing:
https://goo.gl/images/fvj858

Which is allready on every (modern) airplane.

Amiga500 wrote:

**However**, it has gave me another thought. We don't necessarily need to even know airspeed, we need to know actual angle of attack. So have a hung vane on the side of the aircraft (similar to the guide vane you see at the tail of a wind turbine or anemometer, example below) - looking at it now - it probably should be a standard continuous feedback instrument and not merely warning of approaching stall via the shaker/audible alarm.

So the pilots have attitude indicator, they have throttle and they have real angle of attack. That should be all they need to fly the plane safely straight and level until they can get on top of the problem(s).

I believe you just described the Airbus Backup Speed Scale system. (BUSS) that has been discussed here.

I'm not familiar with how the Airbus BUSS system works, but I assume it involves measuring angle of attack by determining the angle of the streamline with the wing. (cough - by definition that would be angle of attack ) Probably have naca scoops on the wing or some other method. I may post in the technical forum about this topic just to get a better understanding personally.

trnswrld wrote:

prebennorholm wrote:

One thing puzzles me. This plane was produced this year 2018. Type certificate is little older. Still:

The memory chips for the FDR and CVR seem to be contained in two different crash and fire resistant units. Each with its own pinger with 30 days pinger battery.

How can that be so? We are writing 2018 today. Are there other plane types, which are produced today with similar recorder configuration?

I refuse to accept that 737MAX flies with the same tape recorders as the 737-200 fifty years ago.

Where are you seeing anything about a tape FDR/CVR?

I maybe wrong but I think prebennorholm is on to something here. Back in the old days, the bulky nature of the recording device meant that the FDR and CVR had to be housed in two separate boxes. With the level of miniaturization we see today using electronics and memory chips, it should be possible to house both in one box. Maybe retain the second combined FDR/CVR box for redundancy in another location of the aircraft in case data from one of them is unrecoverable or is incomplete (as in the case of National Airlines 102).

Erebus wrote:

trnswrld wrote:

prebennorholm wrote:

One thing puzzles me. This plane was produced this year 2018. Type certificate is little older. Still:

The memory chips for the FDR and CVR seem to be contained in two different crash and fire resistant units. Each with its own pinger with 30 days pinger battery.

How can that be so? We are writing 2018 today. Are there other plane types, which are produced today with similar recorder configuration?

I refuse to accept that 737MAX flies with the same tape recorders as the 737-200 fifty years ago.

Where are you seeing anything about a tape FDR/CVR?

I maybe wrong but I think prebennorholm is on to something here. Back in the old days, the bulky nature of the recording device meant that the FDR and CVR had to be housed in two separate boxes. With the level of miniaturization we see today using electronics and memory chips, it should be possible to house both in one box. Maybe retain the second combined FDR/CVR box for redundancy in another location of the aircraft in case data from one of them is unrecoverable or is incomplete (as in the case of National Airlines 102).

Here is a link to a 737NG FDR located above the aft galley ceiling, with the underwater metallic beacon visible:
https://www.facebook.com/737handbook/ph ... =3&theater

You guys go and certify something new that does the same job as something that already exists on aircraft and works fine. Good luck pitching the business case on that. Without regulatory pressure you won't see a change.

Erebus wrote:

I maybe wrong but I think prebennorholm is on to something here. Back in the old days, the bulky nature of the recording device meant that the FDR and CVR had to be housed in two separate boxes. With the level of miniaturization we see today using electronics and memory chips, it should be possible to house both in one box. Maybe retain the second combined FDR/CVR box for redundancy in another location of the aircraft in case data from one of them is unrecoverable or is incomplete (as in the case of National Airlines 102).

Don't want to derail the topic but the subject of the blackbox technology has come up a few times. Aerospace electronics are always several generations behind consumer electronics. For example the F-35 uses PowerPC processors similar to the one that debuted in the iMac G4 sixteen years ago, the processor in even the cheapest Android phone available now would run circles around it. The primary reasons for this are:

1. Aerospace isn't going to touch anything that hasn't been proven reliable by years of use (most people would probably be very surprised at number of "errata" issued for consumer processors where the processors don't perform as specified, the industry just quietly handles these in software and bios updates).
2. The environmental conditions require radiation hardened electronics with greater temperature, vibration, air pressure, etc. ranges.
3. The market for these components is orders of magnitude smaller than commercial components so companies like IBM and Intel can't afford to invest in a design that might not sell or release upgrades at the same pace.
4. The manufacturer also has to commit to supporting the chip/component and providing spares for a reasonable lifespan by aerospace terms, not commercial terms (decades).
5. While Dell can drop the latest version of the i7 into a new desktop with a modest amount of validation, Airbus/Boeing/etc. would have to re-certify everything dependent on that chip and its output (which on a modern fly-by-wire aircraft might as well be everything).

So even after a component has been proven reliable over several years in general commercial use it still has to go through a another design and fabrication phase, then be proven reliable again and then the aerospace companies have to wait for a point in their products life cycle where the impact of the design and validation of a new component using that chip can be justified. The end result is product release cycles and lifespans that are measured in decades, not years.

I'm sure I'm leaving things out, I follow aerospace electronics as a hobby not professionally but the end result is that aerospace, out of necessity and caution, is general 10-20+ years behind "state of the art". That's a good thing but it often leaves people not familiar with the process baffled as to why they have a phone that fits in their pocket that can record 4k video and easily handle all the data points a plane would generate but a "black box" is a clunky device better suited to a 90's recording studio.

sandbender wrote:

Erebus wrote:

I maybe wrong but I think prebennorholm is on to something here. Back in the old days, the bulky nature of the recording device meant that the FDR and CVR had to be housed in two separate boxes. With the level of miniaturization we see today using electronics and memory chips, it should be possible to house both in one box. Maybe retain the second combined FDR/CVR box for redundancy in another location of the aircraft in case data from one of them is unrecoverable or is incomplete (as in the case of National Airlines 102).

Don't want to derail the topic but the subject of the blackbox technology has come up a few times. Aerospace electronics are always several generations behind consumer electronics. For example the F-35 uses PowerPC processors similar to the one that debuted in the iMac G4 sixteen years ago, the processor in even the cheapest Android phone available now would run circles around it. The primary reasons for this are:

1. Aerospace isn't going to touch anything that hasn't been proven reliable by years of use (most people would probably be very surprised at number of "errata" issued for consumer processors where the processors don't perform as specified, the industry just quietly handles these in software and bios updates).
2. The environmental conditions require radiation hardened electronics with greater temperature, vibration, air pressure, etc. ranges.
3. The market for these components is orders of magnitude smaller than commercial components so companies like IBM and Intel can't afford to invest in a design that might not sell or release upgrades at the same pace.
4. The manufacturer also has to commit to supporting the chip/component and providing spares for a reasonable lifespan by aerospace terms, not commercial terms (decades).
5. While Dell can drop the latest version of the i7 into a new desktop with a modest amount of validation, Airbus/Boeing/etc. would have to re-certify everything dependent on that chip and its output (which on a modern fly-by-wire aircraft might as well be everything).

So even after a component has been proven reliable over several years in general commercial use it still has to go through a another design and fabrication phase, then be proven reliable again and then the aerospace companies have to wait for a point in their products life cycle where the impact of the design and validation of a new component using that chip can be justified. The end result is product release cycles and lifespans that are measured in decades, not years.

I'm sure I'm leaving things out, I follow aerospace electronics as a hobby not professionally but the end result is that aerospace, out of necessity and caution, is general 10-20+ years behind "state of the art". That's a good thing but it often leaves people not familiar with the process baffled as to why they have a phone that fits in their pocket that can record 4k video and easily handle all the data points a plane would generate but a "black box" is a clunky device better suited to a 90's recording studio.

Well, the F-35 has been in development / production for about 20 years. Makes sense that they have technology that old in them

sandbender wrote:

Aerospace electronics are always several generations behind consumer electronics. For example the F-35 uses PowerPC processors similar to the one that debuted in the iMac G4 sixteen years ago, the processor in even the cheapest Android phone available now would run circles around it.

I agree that mass produced industrial electronics are less focused on power and performance and more about durability and efficiency than the usual consumer grade versions. This is also very evident in space applications where even the latest rovers have specs that would seem like from the '90s. That's a whole other topic but as far as combined CVR/FDR go, the technology exists today as CVDR (Cockpit Voice and Data Recorder).

https://www.seaerospace.com/sales/product/L3%20Technologies/FA2100%20CVDR

spacecadet wrote:

frmrCapCadet wrote:

For some strange bureaucratic reasoning RRs don't have GPS in locomotives - they rely on computers and central control from a person thousands of miles away.

Trains run on tracks on the ground. It's a one-dimensional mode of transportation. GPS is not really necessary.

On the surface, you'd think so ... but those with RR experience know differently.

A train is not a finite object on a track.

It's a moving object that weighs (for a freight train) as much as a small ship. Freight locomotives, alone, weigh as much as a large fully laden jetliner. Not including the 200 cars of coal behind them, weighing (themselves) as much as a smaller fully laden jetliner ... each.

That moving object is moving on a 3 dimensional track. It has curves. It has hills. There is perhaps TWO MILES of train stretched behind you across all of this.

Knowing exactly where you are, and what's ahead of you, and what your current and approaching speed restrictions are, is crucial to safe operation of your train. Knowing where the OTHER trains are, perhaps isn't your problem, but it sure as heck is the dispatcher's problem, and GPS would only help there.

Okay, so let's say this crash was caused by confusion on airspeed. Is the argument valid regarding newer pilots relying on technology too much? I remember my uncle in law who was a 747 Captain on Northwest telling me that the old stick and rudder pilots are a dying breed.

I still have a hard time believing that airspeed alone could cause such a horrific accident. I am going to guess there was enough daylight so the crew could see terrain, and sky?

prebennorholm wrote:

mandala499 wrote:

- Initial FDR analysis will take 1-2 weeks.
- CVR pings are reported to be "in and out" through this afternoon's search dives.

One thing puzzles me. This plane was produced this year 2018. Type certificate is little older. Still:

The memory chips for the FDR and CVR seem to be contained in two different crash and fire resistant units. Each with its own pinger with 30 days pinger battery.

How can that be so? We are writing 2018 today. Are there other plane types, which are produced today with similar recorder configuration?

I refuse to accept that 737MAX flies with the same tape recorders as the 737-200 fifty years ago.

I imagine this is probably a type certificate thing for the 737 in general, where it's certified for a FDR and a CVR.

for sure many newer planes, like the 787, carry combined data recorders, where each recorder does a mirror image of both the fdr and the cvr data.

prebennorholm wrote:

mandala499 wrote:

- Initial FDR analysis will take 1-2 weeks.
- CVR pings are reported to be "in and out" through this afternoon's search dives.

One thing puzzles me. This plane was produced this year 2018. Type certificate is little older. Still:

The memory chips for the FDR and CVR seem to be contained in two different crash and fire resistant units. Each with its own pinger with 30 days pinger battery.

How can that be so? We are writing 2018 today. Are there other plane types, which are produced today with similar recorder configuration?

I refuse to accept that 737MAX flies with the same tape recorders as the 737-200 fifty years ago.

The FDR & CVR on the 737MAX bare very little resemblance to those on the 737-200. They have been continually upgraded with more capablity and survivability. Because they don't happen to be in the same box doesn't mean they can't perform their required function. They're probably not in the same box because 1) there is no requirement and 2) the airlines buying the 737MAX want to be able to use the same boxes they have on their next gens.

F9Animal wrote:

I still have a hard time believing that airspeed alone could cause such a horrific accident.

It won't have been airspeed (or loss of airspeed measurement to be more precise) alone that caused this tragedy. That may have been the first in a line of dominoes that eventually fell. Look at AF447 for an example of how badly things can go sideways - a disaster that should have been a non-event.

On a side note ......

I just watched a news report on the crash and it showed the wreckage underwater and then a photo of an AirAsia A320..... ?!?!

litz wrote:

prebennorholm wrote:

mandala499 wrote:

- Initial FDR analysis will take 1-2 weeks.
- CVR pings are reported to be "in and out" through this afternoon's search dives.

One thing puzzles me. This plane was produced this year 2018. Type certificate is little older. Still:

The memory chips for the FDR and CVR seem to be contained in two different crash and fire resistant units. Each with its own pinger with 30 days pinger battery.

How can that be so? We are writing 2018 today. Are there other plane types, which are produced today with similar recorder configuration?

I refuse to accept that 737MAX flies with the same tape recorders as the 737-200 fifty years ago.

I imagine this is probably a type certificate thing for the 737 in general, where it's certified for a FDR and a CVR.

for sure many newer planes, like the 787, carry combined data recorders, where each recorder does a mirror image of both the fdr and the cvr data.

I doubt it's part of the type certificate.

scbriml wrote:

F9Animal wrote:

I still have a hard time believing that airspeed alone could cause such a horrific accident.

It won't have been airspeed (or loss of airspeed measurement to be more precise) alone that caused this tragedy. That may have been the first in a line of dominoes that eventually fell. Look at AF447 for an example of how badly things can go sideways - a disaster that should have been a non-event.

An accident is almost never caused by a single event, rather a chain of events...any one of which, if properly dealt with, would have prevented the accident.

An accident, as others have said here, is not by a mere thing, but a chain of errors, mistakes and miscomprehensions that result in deadly or serious consecuences.

Dumb non-pilot question: if the pilots recognize that they have unreliable speed indication, is it better to be fast than slow?

D L X wrote:

Dumb non-pilot question: if the pilots recognize that they have unreliable speed indication, is it better to be fast than slow?

Push comes to shove, in level or semi-level flight, you’d rather be fast than slow. But of course that has a limit. And if you are too fast, you are likely in a dive and you don’t realize it.

I managed to get bits of the previous post flight maintenance reports from various sources. It looks like the unreliable airspeed indications from the last 4 flights may not have been caused by a single generated warning/fault on the sensor detection (ie: not purely a pitot issue).Am now getting info (which needs confirmation) that over the past week, whenever a problem occur, it would appear, get rectified according to the FIM and TSM, then fly again, get the same warning, fix it again, then the aircraft would generate a different problem. If this is true then the guys on the ground had little chance to pick up on them as a "repetitive problem" (which would require a different kind of troubleshooting). When taking a step back, it does appear that this may be an ADR issue (not a sensor input to the ADR, but the ADR itself). The major problem with this, is the STS (Speed Trim System)... which if taking erroneous ADR feeds, could lead to...

So, this morning we had a shocker... if true then... (Am still trying to get to the depths of it)
https://www.bloomberg.com/news/articles ... 7-max-jets
"erroneous readings from a flight-monitoring system can cause the planes to aggressively dive"

and now... this too:
https://theaircurrent.com/aviation-safe ... air-crash/

I guess this is going to be a looooooong case for everyone to deal with...

mandala499 wrote:

I managed to get bits of the previous post flight maintenance reports from various sources. It looks like the unreliable airspeed indications from the last 4 flights may not have been caused by a single generated warning/fault on the sensor detection (ie: not purely a pitot issue).Am now getting info (which needs confirmation) that over the past week, whenever a problem occur, it would appear, get rectified according to the FIM and TSM, then fly again, get the same warning, fix it again, then the aircraft would generate a different problem. If this is true then the guys on the ground had little chance to pick up on them as a "repetitive problem" (which would require a different kind of troubleshooting). When taking a step back, it does appear that this may be an ADR issue (not a sensor input to the ADR, but the ADR itself). The major problem with this, is the STS (Speed Trim System)... which if taking erroneous ADR feeds, could lead to...

So, this morning we had a shocker... if true then... (Am still trying to get to the depths of it)
https://www.bloomberg.com/news/articles ... 7-max-jets
"erroneous readings from a flight-monitoring system can cause the planes to aggressively dive"

and now... this too:
https://theaircurrent.com/aviation-safe ... air-crash/

I guess this is going to be a looooooong case for everyone to deal with...

Wow

Sent from my SM-T810 using Tapatalk

Interesting development. Question I have is, if such issues have surfaced on other MAXes flying even if they were not immediately detected, or if this particular Lion Air aircraft presented the first known instance of such a problem.

Question for pilots only - this new revelation by Boeing that erroneous readings in the speed trim system can lead to a steep dive is quite shocking.
Suppose the plane is at a low height like at 5000 ft while taking off or landing , will you have enough time to react ?
Because assuming a cruising speed of around 700 ft per sec of the plane , it will take a plane just 7 secs approx to reach ground level from 5000 ft .

Wow is correct.

This is the first I've heard of automatic AoA protection on a Boeing. Is it new to the Max? And is it as comprehensive as the Airbus logic?

mandala499 wrote:

I managed to get bits of the previous post flight maintenance reports from various sources. It looks like the unreliable airspeed indications from the last 4 flights may not have been caused by a single generated warning/fault on the sensor detection (ie: not purely a pitot issue).Am now getting info (which needs confirmation) that over the past week, whenever a problem occur, it would appear, get rectified according to the FIM and TSM, then fly again, get the same warning, fix it again, then the aircraft would generate a different problem. If this is true then the guys on the ground had little chance to pick up on them as a "repetitive problem" (which would require a different kind of troubleshooting). When taking a step back, it does appear that this may be an ADR issue (not a sensor input to the ADR, but the ADR itself). The major problem with this, is the STS (Speed Trim System)... which if taking erroneous ADR feeds, could lead to...

So, this morning we had a shocker... if true then... (Am still trying to get to the depths of it)
https://www.bloomberg.com/news/articles ... 7-max-jets
"erroneous readings from a flight-monitoring system can cause the planes to aggressively dive"

and now... this too:
https://theaircurrent.com/aviation-safe ... air-crash/

I guess this is going to be a looooooong case for everyone to deal with...

Wow, and here we have the counter argument to relying on automation. In a Cessna 172 I fly... you fly the freaking plane. lol.

benjjk wrote:

Wow is correct.

This is the first I've heard of automatic AoA protection on a Boeing. Is it new to the Max? And is it as comprehensive as the Airbus logic?

I dont think so. This is from a 737NG training slide

It's hard to imagine what the pilots would be thinking as the plane forcibly steers itself into the ground, possibly just a matter of seconds to an unrecoverable dive. Terrible. Would like to see the DFMEA on this system, I would ope that the engineers would not allow a single failure to cause that.

By the way, hi guys. Long time engineer, systems prototyper, not a pilot.

So basically Boeing has been adding elements of the envelope protection to the 737MAX which if given errorneous inputs can crash the plane?

frmrCapCadet wrote:

I follow RRs pretty closely. There have been 3 multi-fatality accidents in the last several years where the engineer did not know where his train was. One of them may have been in a tunnel where GPS is not available. You cannot tell where you are by 'just looking out the window, that is a pretty ignorant belief. Amongst other things sometimes it is dark outside.

Engineers are qualified over territory, and generally they are expected to know where they are by looking out the window, reasonable or not.

mandala499 wrote:

The major problem with this, is the STS (Speed Trim System)... which if taking erroneous ADR feeds, could lead to...

I was told the STS has its own sensor, not off the ADR.

Erebus wrote:

Interesting development. Question I have is, if such issues have surfaced on other MAXes flying even if they were not immediately detected, or if this particular Lion Air aircraft presented the first known instance of such a problem.

Holy crap. No issues has been officially identified yet. The supposed source for this fake news remained anonymous. If people buy into unsubstantiated fake news the journalist's payday is assured. Watch for the slim possibility of a teeny tiny retraction on the last page if the reporting was not factual and correct.

stratclub wrote:

Erebus wrote:

Interesting development. Question I have is, if such issues have surfaced on other MAXes flying even if they were not immediately detected, or if this particular Lion Air aircraft presented the first known instance of such a problem.

Holy crap. No issues has been officially identified yet. The supposed source for this fake news remained anonymous. If people buy into unsubstantiated fake news the journalist's payday is assured. Watch for the slim possibility of a teeny tiny retraction on the last page if the reporting was not factual and correct.

This piece of news/fakenews/whateveryouwanttocallitnews seems to be Bloomberg:

https://www.bloomberg.com/news/articles ... 7-max-jets

They have even updated the page after issuing it, with no sign of retracting anything. I don't know, but this does seem to fit to the profile of the accident. Just scary to think if the plane can actually do that.

MaksFly wrote:

Wow, and here we have the counter argument to relying on automation. In a Cessna 172 I fly... you fly the freaking plane. lol.

Only you would not be wiling to accept the higher GA crash rate for an airliner, right?

GA ~~~1/100k hours

CA ~~~1/250m departures ( ~~ 1/500m hours ?? )

stratclub wrote:

Holy crap. No issues has been officially identified yet. The supposed source for this fake news remained anonymous. If people buy into unsubstantiated fake news the journalist's payday is assured. Watch for the slim possibility of a teeny tiny retraction on the last page if the reporting was not factual and correct.

So anything you don't like is "fake news"?

What if Boeing don't deny it?