Air France 447 - On topic only!

[guamainiac]

Has there ever been developed a list and formula for all of the variables that would list the "relevant" and the "spurious" variables possible.

The things TeeVee and Theo have discussed for instance? Airline training, type of oversight by regulators and such?

[Jpmkam]

I hear that they want to try to recover all the cockpit, if they succes they will have the pitot.

I haven't read anything on the condition of the cockpit structure let alone whether the pilots are still in that general area of the wreckage.

[Evan]

Found something interesting skimming through the A330 Flight Crew Training manual.

It indicates that when entering moderate turbulence, a penetration speed should be selected on the FCU instead of using the managed speed function. It further states that when entering severe turbulence, the ATHR should be disengaged and the proper N1 speed manually set.

If severe turbulence is encountered, the flight crew should keep the AP engaged. Thrust levers should be set to turbulence N1 (Refer to QRH), and the A/THR should then be disconnected.

ACARS indicated - .1/WRN/WN0906010210 223002506AUTO FLT A/THR OFF

So the ATHR was in use while penetrating this weather system. That could either mean they were not following the recommendations of the FCTM or they were not experiencing severe turbulence. The ATHR can also be used with the thrust lever angle at a setting below CLB to limit max thrust, but this will result in a repeated caution warning as follows:

However, if all thrust levers are set to below the CLB detent, with the A/THR active, then the ECAM repeatedly triggers the AUTO FLT AUTOTHRUST LIMITED caution. This is because there is no operational reason to be in such a situation, and to permanently limit A/THR authority on all engines. In this case, all thrust levers should either be brought back to the CLB detent, or the A/THR should be set to OFF.

For what it's worth.

EDIT: This is from a KLM FCTM. Air France may have different policies.

[Myndee]

I haven't read anything on the condition of the cockpit structure let alone whether the pilots are still in that general area of the wreckage.

Does he mean the pilot or the pitots? One of the crew was recovered. Mark Dubois was the captain I believe. Please correct me if I am mistaken.

[Joe H]

Hi all
I found it interesting that in the Dominican crash (blamed on pitot contamination as the main culprit) that the pitot area was never recovered. (AFAIK!) . IF it was too expensive or whatever to do so, who knows...

Obviously that tends to 'suggest' only that the Domincan issue was due to the fact the aircraft had sat on the ground apparantly with pitot uncovered, so different case to super cooling etc. I do think though, that in this case, they DO intend to recover as much as is possible of the wreckage, including remains. There is a caveat though, in that contamination of pitot by foreign objects is one thing, issues with super cooled droplets etc is not going to be proven from the pitot alone as all evidence (I think) would be negated by temperature and hence deformation of the culprit.

Like all, the next few weeks should be a real eye opener. !

[Myndee]

If I may, I would like to conduct and informal poll. Responses are appreciated.

Do you believe the crash was caused by a pitot failure of some type?

Do you believe the crash was caused by a structural failure?

Do you believe the crash was caused by pilot error (not configuring the aircraft correctly after the airspeed could not be determined?)

Do you have some other theory?

Thanks for your replies.

[Peter Kesternich]

Would have been easier to reply if the questions were numbered

Do you believe the crash was caused by a pitot failure of some type?

I believe the pitots played a part, but were not the only cause. They were part of the chain of events that led to the crash.

Do you believe the crash was caused by a structural failure?

No, unless it turns out after all, that somehow a bomb on board was responsible. I believe AF447 did not crash because of overloads caused by turbulence or flight control inputs.

Do you believe the crash was caused by pilot error (not configuring the aircraft correctly after the airspeed could not be determined?)

While it would reflect pretty poorly on the airmanship of the AF447 crew, it is quite possible that the crash resulted from mismanagement of erroneous airspeed indications. Wouldn't be the first one in history. I hope (for several reasons) that this was not the cause of the crash, but I believe that it is quite likely the cause and that the investigation will eventually confirm that.

Do you have some other theory?

None that are both realistic and supported by the facts known so far.

Thanks for your replies.

You're welcome

[Theoddkiwi]

Would have been easier to reply if the questions were numbered

+1 agree with all of your answers.

To me the simplest scenario makes the most sense.

Pitots caused a problem, pilots reacted incorrectly, plane crashed.
Its been done many times before. History does repeat itself often.

Its sad to have to point fingers, and i know perhaps one day god forbid i will forget to do something or do it incorrectly and an aircraft crashes. The finger will point at me.
Humans unfortunately are the common denominator for the vast majority of accidents in aviation. After we all only Human.

What i would like to know is what did they do or not do to loose control, and did they ever have a chance once they lost control.

[Joe H]

Great questions from Myndee,
look, at the end of the day, the pilots react to what they have in front of them in light of their training and skills, nothing more, they basically hardly ever 'fly' the aircraft, they control the computers.
When the excrement hits the rotary oscillator, then all hell breaks loose.. unless they have vast amounts of real world stick and rudder, AND the aircraft even allows that minimal control... The Gimli Glider, was brought down by an pilot basically familiar and up to date with side slip, Look at the Colgan issue, both were cockpit sim pilots in reality, and I think the result was because the pilot THOUGHT he was in a tail stall, although he wasn't.. he did what he had seen, not what he had practiced.. the Airbus that lost it's tail fin was overcorrected by the pilot(s) leading to massive overloading of the airframe. Yes, there is a debate as to IF the control input should have been allowed.. but....

I, like all, await the results, I am sure it is not an airframe failure, it will almost certainly be BLAMED on the pilot's incorrect action.. however right or wrong that may me.
Most ariline pilots these days are the result of a Zero to Hero course... Look at the Colgan FO transcripts, she was in no way ready to be promoted. let alone fly second fiddle, the pilot was also of dubious 'management' ability. But, that is part of the cycle, if a country pays someone to serve big macs more than a pilot in charge of a jet airliner, then there is something wrong. the standards are lowering and the sooner we move to automated flight the safer it will be, again, with a caveat, that the TRUTH comes out re all incidents which rarely happens, but if and when this can be programmed into the computers, they will react far far better than the human input. In 10 to 20 years, I do not think a human will be anywhere near the flight controls, WITH the right control software, it will end up in a safer flying environment.. of course, there are issues with this... but mainly a perceptive issue...
Human pilots are going to be phased out, and the sooner the better.. then we start the learning curve of what we KNEW, and what we LEARNT, and then feed that back to computers with failsafe backup, ... the real issue is, what we KNEW is based on human input and political and financial infighting, what we have learnt, is also based on that
We need to remove the human aspect from control.

So many times the systems fail, then the pliots crash the aircraft.. so reomve either the systems or the pilots.. however, the systems allow zero to hero pilots... so remove them and improve the systems.. everyone wins.. flying becomes safer. It is not a pipe dream, it is reality...the only thing is how long it takes.

[ultraflight]

Pitots caused a problem, pilots reacted incorrectly, plane crashed.
Its been done many times before. History does repeat itself often.

Agree.
Strange speed indications, darkness, no visible horizon, turbulence, thunderstorm, lightning: adrenaline, wrong conclusions... horrible moments.

[Evan]

Do you believe the crash was caused by a pitot failure of some type?

I believe pitot failure set in motion a cascade of critical system failures that are dependent on airspeed data. Especially things like autopilot and yaw damping, things that are key to maintaining control in moderate to severe turbulence at that altitude. As MCM pointed out, aircraft like this are not designed to be hand-flown in high-altitude, low density air and, without these corrective systems, pilot inputs need to be very precise to avoid things like dutch roll and axial excursions that can cause further g-loading.

Do you believe the crash was caused by a structural failure?

I think it is possible that some control surface(s) might have been shed, but the evidence indicates that the aircraft was otherwise intact and controllable to a certain degree.

Do you believe the crash was caused by pilot error (not configuring the aircraft correctly after the airspeed could not be determined?)

We have learned that, in the 13 other reported instances of UAS studied in the investigation, there was not a single case where the memory items were actually performed. It's reasonable to believe that the crew of AF447 also did not have these memory items properly instilled in their training. But, you have to draw a fine line here between 'pilot error' and 'pilot limitation'. Under the conditions they were probably encountering (turbulence, darkness, loss of airspeed data, loss of autoflight, loss of flight augmentation and a barrage of confusing ECAM messages, all occurring near the limit of their flight envelope), I think we may find that it would have been extremely challenging to avoid errors (by the estimations I've seen (205t, ASI +13) their service ceiling would have been around 37,500ft, before any G-loading or gust-loading).

I believe these memory items have since been revisited and potentially modified as a result.

Do you have some other theory?

The UAS memory item calls for a thrust lever setting, not an N1 setting. I still wonder if the detent-driven A/THR (which varies thrust without moving the levers) and the Thrust-Lock function might have played a role. It is highly likely that the autopilot was slowing the aircraft to turbulence penetration speed at some time before the airspeed data was lost. If the pilots wanted CLB thrust as a memory item and the A/THR had disconnected due to failure, there are only two ways to get out of Thrust-Lock and restore full CLB power setting: you must either move the lever out of the detent and then back into it, or you must press the instinctive disconnect switch on the thrust lever (if this method will even work after the A/THR has failed). Both of these actions seem counter-intuitive to me. The only actual means of verifying power setting are the TLA and engine indications on the LCD's, which may have been initially overlooked by an overwhelmed crew in a violent situation (remember: the memory item calls for verification of thrust lever setting, not N1 indication).

Getting back to pilot error, it might also have been against SOP to enter this heavy turbulence/weather system with the A/THR engaged.

Assuming the recorders don't reveal something new and unanticipated, I would hope for the following recommendations:

- Explore more robust pitot probe designs
- Study and revise memory item procedures for unreliable airspeed at cruise altitude to unsure they are realistic and effective for the situation encountered.
- Improve crew training of the unreliable airspeed procedures during cruise phase of flight.
- Improve crew training on the use of A/THR during severe turbulence and/or A/THR failure.
- Improve crew training for predicting weather systems in the ITCZ
- Conduct more in-depth studies of weather phenomena in the ITCZ.
- Require a more detailed study of essential system interdependencies during the certification process.

[Evan]

Most ariline pilots these days are the result of a Zero to Hero course... Look at the Colgan FO transcripts, she was in no way ready to be promoted. let alone fly second fiddle, the pilot was also of dubious 'management' ability. But, that is part of the cycle, if a country pays someone to serve big macs more than a pilot in charge of a jet airliner, then there is something wrong.

While that may have been true of the Colgan crash, the Air France pilots aboard AF447 were very well experienced and capable, though not necessarily prepared for what they encountered. I don't think what you say is true of most airline pilots, but is undoubtedly true of certain pilots and operators.

[Joe H]

While that may have been true of the Colgan crash, the Air France pilots aboard AF447 were very well experienced and capable, though not necessarily prepared for what they encountered. I don't think what you say is true of most airline pilots, but is undoubtedly true of certain pilots and operators.

Absolutely Agreed Evan !

I was using that as an example of the Zero to Hero training,

You are totally correct, it is not approriate for all and I did not mean it that way, I stand corrected, but the concept is correct, the more time passes, the more that time served pilots in the real sense fall out of the loop, hence the Zero to Hero ! the days of the 'real' pilot who can actually fly an aircraft are numbered, we just now have sim trained button press heroes who will and do panic the moment a crisis hits. and they can do no more, because they were not in charge of a Lancaster Bomber or B17 etc... they are a completly new breed, trained to manage the instruments, and only fly the aircraft in a real shit hit situation, previously, they were true airmen, who were then trained to use the additional instruments.

Joe.

[Jpmkam]

Photo of cockpit voice recorder as it was found on the ocean floor by the remote submarine REMUS 6000.

[MCM]

While much of what you say is true Joe, don't forget the fact that the old school style of aviating had more than its fair share of problems, and there are many accidents directly attributable to the styles of some of these guys.

Those "true airmen" you describe, while many of them were and are excellent aviators, were not all without fault. Accident rates have decreased, not increased, in the modern days of the 'zero to hero' pilot. What has changed is the cause of the accident.

Airbus themselves have acknowledged that the pilot has been left out of the system too much, however there seems a real reluctance by the industry to take any positive steps towards putting more manual control back in the pilot's hands. Its a catch 22.

You want your pilot to be current and well practiced at hand manipulation of the aircraft for the emergency situation, however he is often prevented from flying the aircraft in even good conditions as statistically it is safer with the automatic systems engaged.

I do still laugh at the reasons for removing the pilot from the cockpit, and the false economy around it. Many of the accidents we see are occuring DESPITE the best efforts of manufacturers to make their aircraft foolproof. Its time people got their head out of the sand, stopped wishing for the pilotless aircraft, and started putting some effort into ensuring the pilot-aircraft interface is optimised to improve safety.

We will be far safer when we actually take that step back from total automation to put the human right where he belongs... at the centre of the loop. Give the required training, and ensure the information he needs is provided in the best way possible for human interpretation and awareness.

At the end of the day, however, the public gets what it asks for. The public demand dirt cheap fares, and so corners need to be cut. At the moment it is wages of staff - that seems to be the way to cut costs. Of course, its all based on the concept of affordable safety, and the odd aircraft loss here and there is more than acceptable to many parts of the industry as it is still the cheaper option.