Air France Flight 447: 'Damn it, we’re going to crash’

[OmniAtlas 93]

A good writeup by the Telegraph, I know this has probably been argued to death already, but the final report is coming out soon.

 

http://www.telegraph.co.uk/technology/9231855/Air-France-Flight-447-Damn-it-were-going-to-crash.html

[FLEX1978 373]

Yep it has been discussed to death

[MMartinov 48]

It is a very good descriptions of what has happened there though in the wrong subforum.

Sad story for a sad airline... Shame for the lost souls.

[OmniAtlas 93]

Reading the Telegraph first hand accounts comments (ho ho ho), it appears Air France wasn't run very well.

[IFR7700 228]

It's as if none of the three experienced commercial pilots ever looked at the attitude indicator. To me, the attitude indicator is the #1 instrument on a scan. All they had to do is fly like a student pilot is trained from the beginning, or simply let go of the controls. Truly baffling.

[zmak 331]

its scary what happened in the cockpit and was recorded and released. The 1st officer was pulling on the non moving joystick and didn't tell anyone, simply amazing and they couldn't see him doing it because airbus uses a pressure sensing stick

[nrunning24 151]

Just to clarify because I see this misunderstanding all the time. There is a huge difference between fly by wire and airbus' laws. Fly by wire just means that the pilot does not physically move the control cables. What people normally mean is airbus laws and how the computer can protect the aircraft from stalls, overspeed and excessive banking. The 777 and 787 are both fly by wire but don't have these protections. Hence why i think its funny when people ask if developers are going to model fly by wire because technically every plane for FS is fly by wire.

[kevinh 409]

its scary what happened in the cockpit and was recorded and released. The 1st officer was pulling on the non moving joystick and didn't tell anyone, simply amazing and they couldn't see him doing it because airbus uses a pressure sensing stick

The Airbus does not use a pressure sensing stick and it certainly does move.

 

Just to clarify because I see this misunderstanding all the time. There is a huge difference between fly by wire and airbus' laws. Fly by wire just means that the pilot does not physically move the control cables. What people normally mean is airbus laws and how the computer can protect the aircraft from stalls, overspeed and excessive banking. The 777 and 787 are both fly by wire but don't have these protections. Hence why i think its funny when people ask if developers are going to model fly by wire because technically every plane for FS is fly by wire.

To clarify your clarification, the 777 and 787 both have similar protections to FBW Airbus. The difference is that the Boeing philosophy is to increased stick forces rather than modify the inputs to limit attitudes. To exceed the limits the Boeing pilot has to overcome this extra resistance. In both Boieng and Airbus FBW in normal operation the pilot's inputs are modified to achieve the result required, it's rather like CWS autopilot operation.

 

As for FS, what you say is untrue, because the surfaces are directly proportional to the control inputs. Default simulation does not allow modification of those inputs. A developer simulating FBW needs to bypass that inherent modelling in some way.

[nrunning24 151]

To clarify your clarification, the 777 and 787 both have similar protections to FBW Airbus. The difference is that the Boeing philosophy is to increased stick forces rather than modify the inputs to limit attitudes. To exceed the limits the Boeing pilot has to overcome this extra resistance. In both Boieng and Airbus FBW in normal operation the pilot's inputs are modified to achieve the result required, it's rather like CWS autopilot operation.

 

As for FS, what you say is untrue, because the surfaces are directly proportional to the control inputs. Default simulation does not allow modification of those inputs. A developer simulating FBW needs to bypass that inherent modelling in some way.

While somewhat correct the 777 and 787 don't have near the amount of computer protection as Airbus aircraft. Boeing design philosophy has always been and will always be the pilot should be the ultimate authority not the computer. And all PC aircraft are fly by wire because you the pilot are NOT moving the control cables (because they don't exist, your on a computer.)

[kevinh 409]

A good writeup by the Telegraph, I know this has probably been argued to death already, but the final report is coming out soon.

 

http://www.telegraph...g-to-crash.html

That Telegraph write up presents the sidestick argument as if it is central to the crash. This is just a speculative debate being had between the proponents of Boeing's design philosphy and the proponents of Airbus philosophy. The BEA reports don't blame sidesticks. Surely it's best to wait for the final report to come out rather than prejudge things with links to journalistic speculation. Journalists are notoriously inaccurate in their reporting of technical matters.

[kevinh 409]

While somewhat correct the 777 and 787 don't have near the amount of computer protection as Airbus aircraft. Boeing design philosophy has always been and will always be the pilot should be the ultimate authority not the computer. And all PC aircraft are fly by wire because you the pilot are NOT moving the control cables (because they don't exist, your on a computer.)

The protections in a Boeing are still as strong, they just operate differently. And since the Airbus prevents AOA from exceeding the angle at which lift is maximum what would be the point in pulling harder (and so decreasing lift)? Both Airbus and Boeing pilots have full authority over the computers except at the limit, beyond which there is no point in going.

 

The Air France A330 was not in Normal Law so the protections you talk about weren't operating anyway. If they had been the aircraft would not have stalled at all.

 

You are wrong about FS aircraft all effectively being FBW. FBW allows the computer to vary the response to the input applied. FS does not do so. FBW is not just replacing the linkages and gearing with a computer which simply says

 

elevator angle = k * control input

 

as is the situation in FS. In FBW,

 

elevator angle = f(control input, AOA, normal acceleration, IAS, etc.)

 

Essentially in FS it's like FBW in Direct Law. It requires additional modelling to create the effect FBW has on aircraft handling, and also the various protections that are available.

[nrunning24 151]

You are wrong about FS aircraft all effectively being FBW. FBW allows the computer to vary the response to the input applied. FS does not do so. FBW is not just replacing the linkages and gearing with a computer which simply says

 

elevator angle = k * control input

 

as is the situation in FS. In FBW,

 

elevator angle = f(control input, AOA, normal acceleration, IAS, etc.)

 

Essentially in FS it's like FBW in Direct Law. It requires additional modelling to create the effect FBW has on aircraft handling, and also the various protections that are available.

 

I think you are taking this a step to far. yes FBW ALLOWS the computer to vary the responce to the imput applied. However that does not mean that it needs to. The invention on FBW has allowed aircraft manufactures to include computer stablizations in their design (why wouldnt you). However you could create a FBW system that does none of this. You could create a FBW 737 that responds the exact same as the current one. Doesnt mean that its not FBW.

 

"Essentially in FS it's like FBW in Direct Law. It requires additional modelling to create the effect FBW has on aircraft handling, and also the various protections that are available." Exactly!!! FBW does not need to include protections.

 

I understand what you are trying to say, however FBW in itself does not need to have any protections and can be just a "driect law" kind of situation. All to often i see people confusing these two different terms, thats all im trying to say.

[kevinh 409]

I think you are taking this a step to far. yes FBW ALLOWS the computer to vary the responce to the imput applied. However that does not mean that it needs to. The invention on FBW has allowed aircraft manufactures to include computer stablizations in their design (why wouldnt you). However you could create a FBW system that does none of this. You could create a FBW 737 that responds the exact same as the current one. Doesnt mean that its not FBW.

 

"Essentially in FS it's like FBW in Direct Law. It requires additional modelling to create the effect FBW has on aircraft handling, and also the various protections that are available." Exactly!!! FBW does not need to include protections.

 

I understand what you are trying to say, however FBW in itself does not need to have any protections and can be just a "driect law" kind of situation. All to often i see people confusing these two different terms, thats all im trying to say.

So you appear to agree that FS can only simulate a simple fixed relationship between control input and surface output.

 

Earlier you said

Hence why i think its funny when people ask if developers are going to model fly by wire because technically every plane for FS is fly by wire.

 

I can't think of a single digital FBW aircraft (civil or military) which does not modify the control input in some way. Default MSFS cannot do this, so to simulate the way FBW works in such an aircraft in FSX without additional modelling is not possible. FBW is not just about envelope protection. No line pilot should ever get anywhere near the protections, but they will all encounter the way FBW affects aircraft handling.

[vololiberista 205]

The is is a red herring! All three pilots did not correctly monitor each nor did they read what the instruments were telling them. Perhaps the only thing that may have confused them was nothing to do with the side stick but the stall warning ceased when the stick was pulled fully back becasue the parameters were "out of range" The stall warning should have sounded continuously. Maybe then the penny might have dropped in time to save the a/c. Pilot error x3. The captain had no business at all to leave the cockpit (leaving two junior pilots in charge) with an approaching storm especially as he had elected to fly through it.

Airbus would correctly argue that the pilots paid no attention to the instruments nor did they fly attitude / thrust for the period that there was no reliable airspeed indication. Basically they all reacted as if they were passengers with absolutely no flying experience at all who would react to a high rate of descent by pulling the stick up. Not knowing anything about a stall.

Presumably during all three pilots basic training in France stalling was covered??

The Name "Air Chance" used in the fifties (because they had so many accidents) looks like being resurrected!

vololiberista

[FLEX1978 373]

While you type that from the comfort of your home after nearly 3 years of analysis since the crash, it may be a good idea to read the transcript again whilst keeping in mind they only had 3 minutes to figure it all out 

 

 

 

Okay on est en TOGA = We are at TOGA

 

En alti on a quoi là = What is our altitude?

 

 

(…) C’est pas possible = It is not possible (Capt)

 

En alti on a quoi = What is our altitude?

 

Comment ça en altitude ? = How can that be our altitude?

 

 

Ouais ouais ouais j’descends là non = Yes Yes Yes I am descending (there), no?

 

 

Là tu descends oui = Yes you're descending

 

 

Hé tu tu es en… Mets mets les ailes horizontales = Hey you...you are...Level your wings! (Capt)

 

Mets les ailes horizontales = Level the wings! (other co-pilot)

 

C’est ce que je cherche à faire = That is what I am trying to do

 

 

Mets les ailes horizontale = Level your wings (Capt)

 

End of stall warning then stall warning again.

 

Stall warning ends

 

 

Je suis à fond à… avec du gauchissement = I am at the limit ... with (left aileron)

 

 

Le palonnier = The rudder

 

Qu’est-ce qu’y… comment ça se fait qu’on continue à descendre à fond là ? = What the...how is it that we are continuing to descend at the max rate?

 

 

Essaye de trouver ce que tu peux faire avec tes commandes là-haut Les primaires et cetera = Try see what you can do with your controls (on top?) the primaries etc

 

 

* au niveau cent = level 100

 

Neuf mille pieds = 9000 feet

 

Doucement avec le palonnier là = Easy with the rudders (Capt)

 

 

Remonte remonte remonte remont = climb climb climb climb (or pull up)

 

Dual inputs

 

 

Mais je suis à fond à cabrer depuis tout à l’heure = but I've been full nose down for a while

 

 

Non non non ne remonte pas = no no no dont pull up (Capt)

 

Alors descend = then descend (pnf)

 

 

Alors donne-moi les commandes à moi les commandes = Then let me take the controls (pnf)

 

Vas-y tu as les commandes on est en TOGA toujours hein = Go, you have control we are still at TOGA hey..

 

 

Attention tu cabres là = Careful you're diving (Capt)

Je cabre ? = I'm diving?

Ben il faudrait on est à quatre mille pied = Ben it will be necessary, we are at 4000 feet

 

GPWS Sink rate Pull up 3X

 

Allez tire = Go, pull! (Capt)

Allez on tire on tire on tire on tire = Go, we pull we pull we pull

 

End of recording