Any updates on the Airbus lost in the Atlantic?

The attitude indicators were presenting an accurate picture of the aircraft's attitude the entire time. All three of them.

For that matter, the airspeeds were valid most of the time as well.

 

Recommendations and BEA findings here:

http://www.bea.aero/en/enquetes/flight.af.447/point.presse.05juillet2012.en.php

 

" Sully" was interviewed last night on CBS regarding the AF incident. When asked about the two junior pilots making opposing control inputs he demonstrated how normal mechanically interconnected control yokes in a Boeing simulator show both the pilots what is going on. Then he commented, " If it had been a Boeing airplane , the crash would never have happened."

 

I still don't understand why the 32 year old copilot pulled back on the stick when he lost the panel and why somebody didn't see the correlation of airspeed and attitude if they were operable. Every instrument rated pilot with whom I have flown in IFR has a panel scan sweeping the panel.

 

Ouch

 

A breakdown in basic airmanship and energy management (such as is required in a glider) -- Maintain aircraft control, return to level flight, then assess the state of your machine. The autopilot was tripped off due to the initial loss of airspeed indications, as designed (airspeed indications came back later) so they had full authority from the system to control the aircraft but somehow took the wrong action. Were they trying to power through the stall with full thrust and raising the nose (since they were losing altitude so they thought they should climb, naturally) ?

Are airline pilots now taught to minimize altitude loss in a stall by using the engines to apply brute force through the stall. Yes, that can work unless you pull up so much that you stall it at full thrust, since it does not have a thrust to weight ratio of more than 1 and even an F-15 can only sustain a vertical climb so long. Not a very good airmanship technique to use the engines for apply brute force rather than manage the energy and physics/aerodynamics (like a glider) to trade altitude for airspeed.

Their reaction was like a paniced, non-pilot using his natural instincts: Trees are getting bigger in the windscreen so one would naturally pull up. They kept dropping so they pulled up even more which caused them to drop even faster rather than less. So, it seems they recognized they were descending, applied full power and pulled up, but too much, stalled it, did not recognize the stall and then could not understand why they were still falling. Then they thought something else must be wrong (loss of control surfaces or mechanical failure, etc) that would not allow them to arrest the altitude loss (like wind shear???). So, they keep pulling back to climb but forgot that it can also kill lift if too much, which causes it to fall out of the sky. Speed is life, trade altitude (Potential Energy) for airspeed (Kinetic Energy) – all just energy management, like a glider has to do.

So, does the human-machine interface have a design flaw and training too since they ignored what the machine was trying to tell them or just did not believe any of their instruments, it seems, of which some were initially wrong but did come back to read correct airspeed, etc ? Probably some of both, improve the design and train pilots better in basic airmanship -- FLY THE AIRPLANE, DON'T LET IT FLY YOU and understand basic aerodynamics. A dog house or a flat plate (like your hand out the car window) will fly with enough brute force thrust but has high drag at high pitch angle and will stall (unless there is a rocket engine on it) and fall out of the sky. That is why they say – SPEED IS LIFE but not necessary always by means of engine power, but also pure aerodynamics/energy management. A basic CL (lift coefficient) versus Alpha (angle of attack) curve shows the increase in lift at low angles but also the sharp drop-off/cliff at high angles of attack. I am an aeronautical engineer and past pilot so I have that curve etched in my mind but I don’t think a lot of pilots remember that from their initial studies many years ago.

This type of accident is happening too much so there is an airmanship/training problem and/or the human-machine interface in the cockpit is not designed properly to get through to the pilot so he does the right thing. It is probably some of both but is happening more often in this age of autopilots doing everything and less and less actual time at the controls. Pilots are typing into a mission computer and setting the autopilot, then just managing/checking the system. But, the pilot is there for the times when the inputs into the automated system go bad and to fly the aircraft, first and foremost. So, there is some amount of pilot error here – the automated system was off so they had full authority to control a flyable aircraft and took the wrong action (applying full power and pitching up rather than dipping the nose to regain airspeed, like a glider would). The system did not fly the airplane into the ground, three humans did. More time or any time flying a glider would teach that. Unfortunately, many pilots have never done that.

 

very nice input and like I said before, " Altitude is airspeed and airspeed is altitude."

 

Actually the "latest" stall recovery technique that is recommended by Airbus and Boeing is to lower the nose and recover and then to apply power. Airbus got behind this after they had an aircraft go down when the aircraft entered a second stall that was exacerbated by the full power recovery with the trim set in a nose up position (it failed to auto trim due to a speed sensor problem coupled with a AOA sensor problem). Aircraft with engines below the wings have a large pitch up response to full power at low speed and unless the airplane is trimmed properly adding full power can result in a pitch up and a subsequent second stall event. Airbus campaigned for this for good while, and Boeing now recommends the same procedure.

Minimizing altitude loss was taught because the probability of a stall was considered to be greatest at low altitude (when the airspeed is low during approach or just after takeoff). For this reason the concept of minimum altitude loss actually has merit, since if you stall when you are low and slow the ground is likely to come up and smite you.

You stall because you don't have airspeed for the G loading you are trying to maintain. You can trade altitude to get that airspeed, or you can add power to accelerate, or you can do both. I'd prefer that the pilot take control, and fly the airplane, which means lower the nose, get airspeed, and if he is low, he needs to add power too.

In small aircraft the pilot has a key element of control force feedback. That is, at very low speeds the controls get really light and that tells the pilot that he is slow. As speed increases the controls get heavy. Even without an airspeed indicator, control feel gives the pilot a lot of feedback as to what the airplane is doing. This is synthesized in larger aircraft, but it doesn't exist in the Airbus aircraft, the stick simply moves against a spring. If you've ever tried to fly an airplane on the computer with a simple spring stick you will understand that it's a lot harder to fly the computer than it is a real airplane.

I still would like to see what the recommended actions are that come out of the inquiry.

 

The lack of airmanship reminds me of the infamous "Staines disaster" that befell a BEA Trident after takeoff from Heathrow in 1972:

http://en.wikipedia.org/wiki/British_European_Airways_Flight_548

 

With powered controls on large aircraft, the pilot has no feel, as stated. On the KC-135 there was a Q Bellows that detected dynamic pressure by means of a Q Bellows intake near the base of the vertical fin that fed dynamic pressure to the diaphragm that in turn fed increased loads into the control system when speeds increased. It was a fool proof system and gave the pilots a fairly true feel in feedback when the airplane was fast or slow.I have never heard any complaints from the pilots over the years. To fly with a spring loaded stick and a computer that you hope is telling you what is going on is horrible in my way of thinking.

 

Increasing engine thrust generated a small normal force and thus a pitch up moment for engines forward of the C.G. and pitch down if aft of the C.G. The moment arm is not long for engines under the wing and a little more for aft mounted engines closer to the horizontal tail but very controllable. At low altitude, reducing pitch attitude to level flight and applying thrust may be necessary to minimize altitude loss in a stall and regain airspeed. And it could work at high altitude but the thrust increase is less due to the lower density. Trading altitude for airspeed seems more appropriate.

I don't understand why they continued to maintain aft stick, nose up during the entire descent. I read that the system stopped the stall warnings below 60 knots. Some time near that, the pilot started to push the nose over to regain airspeed (doing the right thing) but after going over 60 knots again but still below stall airspeed, the horn started again and the pilot went back to pulling back on the stick and stayed with that control input until the end. The confusing feedback to his input did not help but there was still a breakdown in airmanship (maintain control and return to level flight) and energy management (trade altitude for airspeed, if you have the altitude, as they did).

If training said to apply thrust to reduce altitude loss and lower the nose to level to get above stall airspeed, then that is fine but they don't seem to have done the second part. Therefore, they continued to fall out of the sky. One can apply full power and still be falling if the angle of attack is too high and the thrust is not enough to overcome the increased drag to regain flying airspeed.

 

Here is a summary of the report that states that during the descent, the flight director was intermittent, but each time it flashed on it told the pilots to pull up....

http://www.ainonline.com/aviation-news/2012-07-08/final-af447-report-suggests-pilot-slavishly-followed-flight-director-pitch-commands

I had not seen or heard of this previously, but it does to some extent explain what they did. If you didn't know you were stalled and the FD said you should pull up, you probably would....

When the instruments are all saying different things, none of which makes sense, which ones do you belive and what do you do???

 

The new info being pushed is 'Sleep Deprivation'... apparently Captain Dubois had only gotten 1 hour of sleep before the flight.

Regardless, it's a huge problem...


Air France Crash: Pilot Marc Dubois Reportedly Was Sleep Deprived - Careers Articles


Reviving an OLD thread...

 

Another recent report
Airbus Test Pilot Says Air France Crash Defeats Simulators - Businessweek

Agree with the first part, but not the last part. If they can't duplicate the behavior in a simulator how could they possibly write code to automate control in this event?

 

Oh, come on. That may well have been the case, but it's not really relevant to this accident. The two trained and qualified first officers on the flight deck should have been able to recover this situation.

No matter how well rested the Captain may have been, it's unlikely he could have leapt up from his bunk, charged to the cockpit, analyzed the situation, and fixed it, in the time available to them.

I wonder if "sleep deprivation" is going to be the new excuse for everything-- I read where Auburn Calloway is claiming that was his problem as well.

 

I agree, Don. The airplane acted like it was having a bad dream so maybe it was sleep deprived ,too.

 

All right...bumping a very old thread, but I thought that some of you might be interested in the judiciary aspect:

Ten years after the Rio-Paris crash, the judiciary matters are at a turning point : the Ministère Public (« Le Parquet », kind of « Director of Public Prosecutions” if you like) recommends prosecuting Air France in a Criminal Court and exonerating Airbus, as no sufficent charge or proof has been brought to light against the manufacturer.

It is now up to the "examining magistrates" ( Juges d'instruction ) to decide whether they will follow these recommendations or not.

The associations of the victims’ families say they are digusted by this decision, infering that, as it has been the matter since the beginning, Airbus manages to always get exonerated of any responsibility, that only the pilots are accused, and they are not here anymore to explain themselves.


http://www.lefigaro.fr/actualite-france/crash-du-rio-paris-le-parquet-demande-un-proces-contre-air-france-20190717



Rgds

 

"no sufficent charge or proof has been brought to light against the manufacturer."

Ridiculous! Any aircraft where one pilot can push the stick forward while the other pilot can pull the stick aft is clearly deficient in design.

 

There is as much reason to blame the pilots for not being able to control the aircraft as there is blame on Airbus for faulty instrumentation.

 

I don't understand this. If you apply the theory of "absent" against it both Airbus and Air France should be held accountable. Absent the Airbus instrumentation failure there would be no crash. Absent the pilot incompetence responding to the instrument failure there would be no crash.

Maybe Boeing ought to hire Airbus's lawyers and appeal to the Director of Public Prosecutions on their 737 Max cases?

 

Please remember that the french law and rights system is different than the one of the United States. Furthermore, it is, for the time being, only recommendations from the "Ministère Public". The "examining judges" are not obliged to follow these.
Rgds

 

10 years on and "no sufficent charge or proof has been brought to light against the manufacturer" seems a bit much......maybe the manufacturers attorneys are more talented/ingenious than the states' prosecutors?

 

As far as we know (all is not public) there has been three different technical expertises (one expertise and two counter-expertises) entrusted to aviation engineers and experts, and these led to the conclusions that there are no sufficent charges to justify a claim against Airbus. As said above, the families of the victims are outraged by these conclusions; Air France is not satisfied either. And, again, this is only the "Ministère Public" recommendations, which weight the legal arguments in the file against the Law, to consider if there is enough evidence for a claim in court. Their advice is that there is enough arguments against Air France for a Criminal Case, not enough against Airbus.
But, in the French Law, the final say (= to prosecute or not) comes from the examining judges ("les juges d'instruction").

Rgds

 

The families are mad because there is no big bucks corporation to sue.