StTim
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Re: S7 flight runs off end of runway, barely takes off

Fri Aug 09, 2019 1:41 pm

Wasn't there an A350 that aborted its take off (and I mean the plane rather than the crew) as it identified they were starting from a different point than the calculated position due to a late ATC request to do an intersection departure?
 
Insertnamehere
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Re: S7 flight runs off end of runway, barely takes off

Fri Aug 09, 2019 1:46 pm

Sounds like Russia, "takeoff normally? screw it we pay for runway we use all runway"

Russia is truly the Florida of the rest of the world.
 
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readytotaxi
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Re: S7 flight runs off end of runway, barely takes off

Fri Aug 09, 2019 2:24 pm

The crew have a grass cutting business on the side.
you don't get a second chance to make a first impression!
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reltney
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Re: S7 flight runs off end of runway, barely takes off

Fri Aug 09, 2019 3:36 pm

Pontius wrote:
aviationjunky wrote:
Why wouldn't they abort take-off if they didn't see the aircraft lifting when it was suppose to??


Takeoff performance is predicated on achieving 3 calculated speeds, most notably V1, "takeoff decision speed." Once the takeoff roll begins, achieving these speeds is the only measurable objective. Runway remaining versus runway required is not known or measured. If acceleration is lower than planned, or if the calculated speeds or thrust setting is incorrect, the scenario in the video happens.

Also, note that in very many takeoffs, V1 occurs mere seconds prior to reaching the end of the runway. In the video scenario, after recognition of a problem there would be an extremely short window in which one had the option of both a successful abort and successfully rotation. Since they lived, it actually looks like they may have made the best of a bad situation.



BIG MISTAKE. V1 does NOT happen a few seconds near the end of the runway!!!! V1 is take off decision speed. IF there is a few seconds till the end of the runway, there would be no runway to stop..... a decision to continue must be made by V1. At V1 is the last place (based on normal acceleration) the plane can abort the takeoff and stop on the remaining runway. If an engine failure happens after V1, there is enough runway to continue and be airborne and you should be at 35ft or better at the end of the runway.


To help many non flyers understand, here is a basic example.
Typical heavy 757#. Would be something like v1 147 VR148 V2 155. On a 10000 ft runway. Let say it was wet or icy those numbers would be V1 125, VR148. V2 155. The runway condition has less friction also your decision speed would be less because it takes more runway on a slick surface to stop so your decision speedV1 has to occur earlier.

Cheers
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OUTLAW KNIVES.

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robsaw
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Re: S7 flight runs off end of runway, barely takes off

Fri Aug 09, 2019 4:19 pm

Lingon wrote:
Having actual acceleration compared to expected acceleration would be neither very hard to implement nor very expensive. There has been too many close calls due to erroneous weights in takeoff calculations.


The plane was probably accelerating as expected - acceleration wasn't the issue, the available runway length was; due to starting the takeoff roll further down the runway than originally entered into the system.
 
Armadillo1
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Re: S7 flight runs off end of runway, barely takes off

Fri Aug 09, 2019 5:26 pm

reltney wrote:
BIG MISTAKE. V1 does NOT happen a few seconds near the end of the runway!!!! V1 is take off decision speed


no, looks like VR does not happen , V1 reached early, but of course too late for normal take off.
and at the moment they reached V1 they may be asknowledge this is no more real V1 and they already passed this point

this is my only opinion
 
Pontius
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 12:18 am

reltney wrote:
Pontius wrote:
aviationjunky wrote:
Why wouldn't they abort take-off if they didn't see the aircraft lifting when it was suppose to??


Takeoff performance is predicated on achieving 3 calculated speeds, most notably V1, "takeoff decision speed." Once the takeoff roll begins, achieving these speeds is the only measurable objective. Runway remaining versus runway required is not known or measured. If acceleration is lower than planned, or if the calculated speeds or thrust setting is incorrect, the scenario in the video happens.

Also, note that in very many takeoffs, V1 occurs mere seconds prior to reaching the end of the runway. In the video scenario, after recognition of a problem there would be an extremely short window in which one had the option of both a successful abort and successfully rotation. Since they lived, it actually looks like they may have made the best of a bad situation.



BIG MISTAKE. V1 does NOT happen a few seconds near the end of the runway!!!! V1 is take off decision speed. IF there is a few seconds till the end of the runway, there would be no runway to stop..... a decision to continue must be made by V1. At V1 is the last place (based on normal acceleration) the plane can abort the takeoff and stop on the remaining runway. If an engine failure happens after V1, there is enough runway to continue and be airborne and you should be at 35ft or better at the end of the runway.


To help many non flyers understand, here is a basic example.
Typical heavy 757#. Would be something like v1 147 VR148 V2 155. On a 10000 ft runway. Let say it was wet or icy those numbers would be V1 125, VR148. V2 155. The runway condition has less friction also your decision speed would be less because it takes more runway on a slick surface to stop so your decision speedV1 has to occur earlier.

Cheers


A long contaminated runway obviously favors an early V1 and a long V1/VR split. A dry, short runway will in fact see a very short window between V1 and end of runway. "Accelerate" distance is proportionally longer than the "Stop" distance.
 
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LAX772LR
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 3:19 am

Surprised that nobody has brought up the China Airlines 737 takeoff overrun at HSG (Saga, Japan) some years back.

Image
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reltney
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 4:07 am

Pontius wrote:
reltney wrote:
Pontius wrote:

Takeoff performance is predicated on achieving 3 calculated speeds, most notably V1, "takeoff decision speed." Once the takeoff roll begins, achieving these speeds is the only measurable objective. Runway remaining versus runway required is not known or measured. If acceleration is lower than planned, or if the calculated speeds or thrust setting is incorrect, the scenario in the video happens.

Also, note that in very many takeoffs, V1 occurs mere seconds prior to reaching the end of the runway. In the video scenario, after recognition of a problem there would be an extremely short window in which one had the option of both a successful abort and successfully rotation. Since they lived, it actually looks like they may have made the best of a bad situation.



BIG MISTAKE. V1 does NOT happen a few seconds near the end of the runway!!!! V1 is take off decision speed. IF there is a few seconds till the end of the runway, there would be no runway to stop..... a decision to continue must be made by V1. At V1 is the last place (based on normal acceleration) the plane can abort the takeoff and stop on the remaining runway. If an engine failure happens after V1, there is enough runway to continue and be airborne and you should be at 35ft or better at the end of the runway.


To help many non flyers understand, here is a basic example.
Typical heavy 757#. Would be something like v1 147 VR148 V2 155. On a 10000 ft runway. Let say it was wet or icy those numbers would be V1 125, VR148. V2 155. The runway condition has less friction also your decision speed would be less because it takes more runway on a slick surface to stop so your decision speedV1 has to occur earlier.

Cheers


A long contaminated runway obviously favors an early V1 and a long V1/VR split. A dry, short runway will in fact see a very short window between V1 and end of runway. "Accelerate" distance is proportionally longer than the "Stop" distance.



Correct . Realize up to the point V1 is reached, you can still stop on the runway. You are correct in it might take 4000ft to get to V1 but 2500 ft to stop deaccelerating from V1. It is a shorter window and you do understand. Pontius was making an incorrect statement saying V1 happened at the end of the runway. He seemed to get it but might have used incorrect words.

Cheers!
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SoCalPilot
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 6:36 am

Lingon wrote:
Having actual acceleration compared to expected acceleration would be neither very hard to implement nor very expensive. There has been too many close calls due to erroneous weights in takeoff calculations.

But that wouldnt change anything, as the airplane would be accelerating as expected based on the erroneous data they inputed.
 
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FredrikHAD
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 8:02 am

If it was a more common problem, there would be a technical solution. TCAS/ADS-B could be used as a base, placing a transmitter at each runway threshold. The system would realize before takeoff was even initiated that something was off if calculations or starting point was incorrect. In case of lack of thrust (compared to the commanded/desired thrust), it would be a little trickier, but certainly doable, to warn or abort automatically during the roll. One simple way would be to compare the desired/pre-calculated V1 point (location on the rwy) to the real point where V1 is acheived. If there’s a will there’s a way.

/Fredrik
 
TTailedTiger
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 8:17 am

Oops, looks like they filled the tanks with vodka instead of Jet A. :duck:
 
CWL757
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 9:14 am

StTim wrote:
Wasn't there an A350 that aborted its take off (and I mean the plane rather than the crew) as it identified they were starting from a different point than the calculated position due to a late ATC request to do an intersection departure?

Yep the first Qatari A350 from JFK- https://youtu.be/MKtPlj932YY
A319, A320, 738, 743, 744, 752, 772, 788, C150, E175, E190, F70, R22
 
b747400erf
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 1:56 pm

Pontius wrote:
aviationjunky wrote:
Why wouldn't they abort take-off if they didn't see the aircraft lifting when it was suppose to??


Takeoff performance is predicated on achieving 3 calculated speeds, most notably V1, "takeoff decision speed." Once the takeoff roll begins, achieving these speeds is the only measurable objective. Runway remaining versus runway required is not known or measured. If acceleration is lower than planned, or if the calculated speeds or thrust setting is incorrect, the scenario in the video happens.

Also, note that in very many takeoffs, V1 occurs mere seconds prior to reaching the end of the runway. In the video scenario, after recognition of a problem there would be an extremely short window in which one had the option of both a successful abort and successfully rotation. Since they lived, it actually looks like they may have made the best of a bad situation.

This is so very inaccurate please name the airplane type you are rated in and fly.
 
b747400erf
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 1:57 pm

Pontius wrote:
reltney wrote:
Pontius wrote:

Takeoff performance is predicated on achieving 3 calculated speeds, most notably V1, "takeoff decision speed." Once the takeoff roll begins, achieving these speeds is the only measurable objective. Runway remaining versus runway required is not known or measured. If acceleration is lower than planned, or if the calculated speeds or thrust setting is incorrect, the scenario in the video happens.

Also, note that in very many takeoffs, V1 occurs mere seconds prior to reaching the end of the runway. In the video scenario, after recognition of a problem there would be an extremely short window in which one had the option of both a successful abort and successfully rotation. Since they lived, it actually looks like they may have made the best of a bad situation.



BIG MISTAKE. V1 does NOT happen a few seconds near the end of the runway!!!! V1 is take off decision speed. IF there is a few seconds till the end of the runway, there would be no runway to stop..... a decision to continue must be made by V1. At V1 is the last place (based on normal acceleration) the plane can abort the takeoff and stop on the remaining runway. If an engine failure happens after V1, there is enough runway to continue and be airborne and you should be at 35ft or better at the end of the runway.


To help many non flyers understand, here is a basic example.
Typical heavy 757#. Would be something like v1 147 VR148 V2 155. On a 10000 ft runway. Let say it was wet or icy those numbers would be V1 125, VR148. V2 155. The runway condition has less friction also your decision speed would be less because it takes more runway on a slick surface to stop so your decision speedV1 has to occur earlier.

Cheers


A long contaminated runway obviously favors an early V1 and a long V1/VR split. A dry, short runway will in fact see a very short window between V1 and end of runway. "Accelerate" distance is proportionally longer than the "Stop" distance.


An airplane is unable to stop "mere seconds" from the end of the runway in good conditions. You are making false statements.
 
greendot
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 2:13 pm

hiflyeras wrote:
vatveng wrote:
bennett123 wrote:
According to Wikipedia, runway 32L is almost 11,500 feet long.

How on earth did a B737NG almost run off the end?.


From the blog post:
The cause of this incident is not yet confirmed; some Russian Aviation websites report that the crew computed takeoff performance using a takeoff weight 15 tons below the real weight, another claims the crew inadvertently entered Zero Fuel Weight instead of the Takeoff Weight.


Any experienced 737 pilot would have known that the thrust was inadequate for the load just by the sound of the engines and the speed they were attaining down the runway. They should have shut things down immediately before getting to this point. They should both be fired.


"Experience" is a nebulous word, like "Airmanship", that is used to account for a lack of education, a bad training program, bad design, manufacturing defects, human error, or an entire system from the company to the government.

The engines don't make a different sound.

USAF pilots used to do "acceleration checks" by checking the amount of time it took to get to runway distance markers. I've never seen the practice in the civilian world. You can't rely on your senses for gauging acceleration. A good headwind or undiagnosed fatigue will give you a false perception.

How could they just shut it down? Do explain,
 
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PW100
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 3:22 pm

triple3driver wrote:
The worst part to me is that not once does something click in either pilot's heads that they don't have nearly enough thrust. And I mean, in the 737, you hit the TOGA switch, and the plane starts to climb very rapidly, seems like even after lifting off they didn't increase thrust, which I just will never understand


I'll bow to your expertise, but to me it seems impossible to judge from that footage alone that they were not in TOGA when the plane started to climb. So many parameters and variables in play such as,
* flap setting
* weight
* air speed
* wind speed and direction
* air tempertaure
* airfield elevation (or actually, pressure altitude)
* dew point
* fuel temp and BTU
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PW100
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 3:28 pm

TTailedTiger wrote:
Oops, looks like they filled the tanks with vodka instead of Jet A. :duck:


Ah, yes, the infamous Vodka-burner!

https://www.youtube.com/watch?v=aWtdtuspnoM
Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
 
peterinlisbon
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 5:32 pm

Perhaps aircraft should have some kind of runway length warning. It seems a bit scary that surviving takeoff depends on whether a zero or a decimal point was put in the wrong place.
 
Q
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 8:06 pm

Maybe either pilot misreading numbers for EPR auto TOGA on taking off mode. EPR should be 1.83. Maybe pilots thought 1.33 or 63. Misread not vision corrected similar 8 with 3 or 6 The pilots set 1.33 or 1.63 It was too low-pressure thrust. 1.83 is more pressure thrust my guess.

What do you think guys? Why would either pilot disconnect autothrottle and push more power before 2,000 ft ahead of end runway? JEESH! Bad judgment!

Q
 
Etheereal
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 8:34 pm

Someone already said it was an intersection TO
JetBuddy wrote:
"737 slides off the runway" is the new "Florida man"..

:lol:
 
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BasilFawlty
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 9:57 pm

peterinlisbon wrote:
Perhaps aircraft should have some kind of runway length warning.

Something like this? ;)
https://en.m.wikipedia.org/wiki/Runway_ ... ory_System
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triple3driver
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Re: S7 flight runs off end of runway, barely takes off

Sat Aug 10, 2019 10:12 pm

PW100 wrote:
triple3driver wrote:
The worst part to me is that not once does something click in either pilot's heads that they don't have nearly enough thrust. And I mean, in the 737, you hit the TOGA switch, and the plane starts to climb very rapidly, seems like even after lifting off they didn't increase thrust, which I just will never understand


I'll bow to your expertise, but to me it seems impossible to judge from that footage alone that they were not in TOGA when the plane started to climb. So many parameters and variables in play such as,
* flap setting
* weight
* air speed
* wind speed and direction
* air tempertaure
* airfield elevation (or actually, pressure altitude)
* dew point
* fuel temp and BTU

I mean, I'll admit that I could be very wrong and the time in the video where the aircraft is off the ground is fairly small, so they could have increased thrust after that, but at least based off that bit, it doesn't look like they did, but don't quote me on that
If you can walk away from it intact, it was a good landing!
 
Pontius
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Re: S7 flight runs off end of runway, barely takes off

Sun Aug 11, 2019 12:06 am

b747400erf wrote:
Pontius wrote:
reltney wrote:


BIG MISTAKE. V1 does NOT happen a few seconds near the end of the runway!!!! V1 is take off decision speed. IF there is a few seconds till the end of the runway, there would be no runway to stop..... a decision to continue must be made by V1. At V1 is the last place (based on normal acceleration) the plane can abort the takeoff and stop on the remaining runway. If an engine failure happens after V1, there is enough runway to continue and be airborne and you should be at 35ft or better at the end of the runway.


To help many non flyers understand, here is a basic example.
Typical heavy 757#. Would be something like v1 147 VR148 V2 155. On a 10000 ft runway. Let say it was wet or icy those numbers would be V1 125, VR148. V2 155. The runway condition has less friction also your decision speed would be less because it takes more runway on a slick surface to stop so your decision speedV1 has to occur earlier.

Cheers


A long contaminated runway obviously favors an early V1 and a long V1/VR split. A dry, short runway will in fact see a very short window between V1 and end of runway. "Accelerate" distance is proportionally longer than the "Stop" distance.


An airplane is unable to stop "mere seconds" from the end of the runway in good conditions. You are making false statements.


Is it minutes then? I'm speaking in generalities for the increasingly adolescent crowd on a.net, not teaching at Cranfield. Just for the sake of curiosity, I checked a couple of RTO videos, an A320 (which I'm typed in) went from ground spoilers up to taxi speed in 9 seconds.
 
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EstherLouise
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Re: S7 flight runs off end of runway, barely takes off

Sun Aug 11, 2019 12:31 am

Viper911 wrote:
GE90man wrote:
Well you know what they say in Russia, pay for the whole runway, use the whole runway


debonair wrote:
GE90man wrote:
Well you know what they say in Russia, pay for the whole runway, use the whole runway


Yeap, seems to me like a normal, old school, Russian take off... Who is not remembering the IL86 take-off from Phuket Airport in the '90s well after the piano keys... :duck:


It has nothing to do with Russia, these type of incidents happen every few years, EK407 in SYD or QR778 in MIA are just to name a few. The difference is that this one was caught on tape. Pilots are human and therefore prone to do mistakes.


That God those pilots didn't let a child into the cockpit to try to take off.
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Varsity1
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Re: S7 flight runs off end of runway, barely takes off

Sun Aug 11, 2019 12:07 pm

maint123 wrote:
No automation system in place to automatically reject obviously wrong weight inputs?
What's the normal weight variation in a similar aircraft?


You guys realize there isn't THAT much automation in airliners right? Even airbus's.
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phugoid1982
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Re: S7 flight runs off end of runway, barely takes off

Sun Aug 11, 2019 1:37 pm

I wonder if a 757 could've made that intersection take/off with a similar incorrect FLEX thrust setting with its superior acceleration performance. It looks like it was a short hop anyway, barely 750 miles but I don't know if they were carrying fuel for the return flight as well in terms of take/off performance. Does anyone the exact distance the pilots has to take/off from the intersection at DME. I also agree acceleration checks based on runway markers regardless would be a good sanity check. Simply a tech question about performance not suggesting we resurrect the Boeing Rocket so keep cool.
Last edited by phugoid1982 on Sun Aug 11, 2019 1:50 pm, edited 1 time in total.
 
b747400erf
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Re: S7 flight runs off end of runway, barely takes off

Sun Aug 11, 2019 1:47 pm

Pontius wrote:
b747400erf wrote:
Pontius wrote:

A long contaminated runway obviously favors an early V1 and a long V1/VR split. A dry, short runway will in fact see a very short window between V1 and end of runway. "Accelerate" distance is proportionally longer than the "Stop" distance.


An airplane is unable to stop "mere seconds" from the end of the runway in good conditions. You are making false statements.


Is it minutes then? I'm speaking in generalities for the increasingly adolescent crowd on a.net, not teaching at Cranfield. Just for the sake of curiosity, I checked a couple of RTO videos, an A320 (which I'm typed in) went from ground spoilers up to taxi speed in 9 seconds.

It takes MERE SECONDS for the pilots to react by starting the rejected takeoff. An airplane is 10-20 seconds from the end of the runway with a properly calculated takeoff configuration. A mere seconds from the end of the runway on normal flight is false and scare mongering.
Last edited by b747400erf on Sun Aug 11, 2019 1:50 pm, edited 1 time in total.
 
b747400erf
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Re: S7 flight runs off end of runway, barely takes off

Sun Aug 11, 2019 1:48 pm

Varsity1 wrote:
maint123 wrote:
No automation system in place to automatically reject obviously wrong weight inputs?
What's the normal weight variation in a similar aircraft?


You guys realize there isn't THAT much automation in airliners right? Even airbus's.

There are automated weight and balance systems in some aircraft models if a company purchases them. We have another person playing a pretend expert in this topic. No wonder the media always gets aviation wrong.
 
slider
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Re: S7 flight runs off end of runway, barely takes off

Sun Aug 11, 2019 2:38 pm

AngelsDecay wrote:
http://avherald.com/h?article=4cb53df5&opt=0

Using 15 tonnes for ZFW instead of TOW its always a nice perspective...OTH you pay for it, you use it ;)

Tanx God "only" 3.500 mts of rwy for a giant 738...


Yeah, if I'm that pilot, I'm firewalling the throttles. Early roll HAD to have been perceptibly slower than expected, one would think. Yeesh.

Like the saying goes, the runway behind you does you no good at some point...
 
Varsity1
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Re: S7 flight runs off end of runway, barely takes off

Sun Aug 11, 2019 2:44 pm

b747400erf wrote:
Varsity1 wrote:
maint123 wrote:
No automation system in place to automatically reject obviously wrong weight inputs?
What's the normal weight variation in a similar aircraft?


You guys realize there isn't THAT much automation in airliners right? Even airbus's.

There are automated weight and balance systems in some aircraft models if a company purchases them. We have another person playing a pretend expert in this topic. No wonder the media always gets aviation wrong.


It's not automated. It's electronically calculated in the runway analysis. Some airlines still do it manually. Both are inputs by humans or from a reservation system.
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tu204
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Re: S7 flight runs off end of runway, barely takes off

Mon Aug 12, 2019 7:11 am

Makes me wonder.

What would have happened if there was an arresting system installed at the end of the runway? The porous concrete kind. Can't imagine it would have been good.
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Spiderguy252
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Re: S7 flight runs off end of runway, barely takes off

Mon Aug 12, 2019 8:10 am

Off-topic, but imagine the storm Boeing will have to face if there was a crash?

Yes yes I know it's an NG and not a MAX, but still.
Vahroone
 
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Lingon
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Re: S7 flight runs off end of runway, barely takes off

Mon Aug 12, 2019 9:44 am

robsaw wrote:
Lingon wrote:
Having actual acceleration compared to expected acceleration would be neither very hard to implement nor very expensive. There has been too many close calls due to erroneous weights in takeoff calculations.


The plane was probably accelerating as expected - acceleration wasn't the issue, the available runway length was; due to starting the takeoff roll further down the runway than originally entered into the system.


Yes, you are right, for this case it was not the weight input that was the problem. However, in my opinion there has been enough cases where the weight has been the culprit to justify an accelerometer check.

SoCalPilot wrote:
Lingon wrote:
Having actual acceleration compared to expected acceleration would be neither very hard to implement nor very expensive. There has been too many close calls due to erroneous weights in takeoff calculations.

But that wouldnt change anything, as the airplane would be accelerating as expected based on the erroneous data they inputed.


No. You input the mass M, and you get a computed (too low) thrust setting and an expected acceleration when that thrust is applied. The actual mass iss M+Me (Me being the difference between the erroneous output and what should have been entered) and with the same thrust setting you get a lower acceleration.

What this will not catch, is a difference in computed Vr (with the erroneous mass) versus needed Vr, and the impact of other settings like how much flaps is needed. Still, I think an acceleration measurement would be able to catch cases where the numbers are way off.

However, as it happened, not applicable in this case.
Last edited by Lingon on Mon Aug 12, 2019 9:58 am, edited 1 time in total.
 
Armadillo1
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Re: S7 flight runs off end of runway, barely takes off

Mon Aug 12, 2019 9:54 am

https://en.wikipedia.org/wiki/Emirates_ ... estigation

In response to the incident, Emirates reviewed its pre-flight procedures, mandating the duplication of laptop computers used for pre-flight planning so as to ensure dual data entry. They are also developing an avionics system for take-off acceleration-monitoring and alerting. Airbus updated its software to detect erroneous data. In October 2011, they announced plans to include a software program to calculate the required runway length. Furthermore, Airbus is developing a monitoring system to compute required acceleration rates and apply a "reasonableness test" to data input and alert the pilot to any potential errors. The system could potentially be certified by 2015


but this can do nothing with wrong runway length input.

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