AF447 wreckage found

[bubbers44]

I once experienced the most dissorienting situation in a Lear Jet when my handflying FO was descending at high altitude and while balancing fuel looked up at the instruments while in the clouds and saw my attitude indicator go through 30 degrees bank and increasing towards redline on airspeed. I felt level as obviously did the FO so it took every bit of discipline to take control and level the three attitude indicators to level flight. I was actually flying sitting leaned over in my seat because I didn't feel level. Experience got us through it, JFK JR didn't fare as well with vertigo. I don't think this would have happened with the captain in his seat even though he was rightfully taking his scheduled rest. I wonder how many hours each of the FO's had of actually flying an airliner without an autopilot in the clouds? My guess is 10 to 30 hrs. Airlines don't want you to handfly any more at a lot of places.

[glad rag]

Having suffered disorientation, just the once, all I can say to anyone who underestimates it's ability to totally deceive you in the most subtle of manners is..

...wake up quick!

No pun intended.

[vovachan]

Something I read: pilots when they become disoriented tend to pull UP. Perhaps this is what we are dealing with here

[bubbers44]

I don't think pilots pull up when they get disoriented unless they are very knew at flying. I saw a Bonanza take off from Burbank, lose an engine, pull up and turn right into a cross control stall that caused them to spin in killing 4 people. More experienced pilots wouldn't have done that. Hopefully some day they will give us some meaningful information of what led up to this accident. So far they haven't told us much of anything even though they have all of the data. We have a lot of experts expounding on their theories with no data however. BOAC, I'm not saying you.

[Machinbird]

When the PF started to apply nose down control in the well developed stall, I wouldn't be surprised if the Captain, who by then had plopped himself into a jump seat, started to float out of the seat and vetoed further tests of that solution. After all, with the engines at idle, someone was probably figuring they might have contributed to the aircraft's pesky ~16 degree nose up attitude.

[Machinbird]

I maintain that a fliable aircraft CFIT is the result of pilot performance. Evident in the last BEA report.

As long as the aircraft was in a stall, it was not flying, and was not under control so CFIT is, in my considered opinion, an overly broad brush for this situation. This is not even remotely like flying into a mountain on approach.

The aircraft was taken outside of its normal flight envelope during cruise. The crew was unable to accomplish the recovery into a normal flight envelope (which was apparently possible given the correct understanding of the situation). Part of the accident investigation will have to focus on why the crew did not achieve correct situational awareness.

Do you think that not having an AOA gage might have been a factor?
It boggles my mind that there are AOA sensors on the aircraft but no real cockpit display.

Yeah, I know, you never flew with it before, so why do you need one now?

[opherben]

Since improper flying technique can get an aircraft into stall, a pilot is trained for and is expected to recover from such condition, promptly and efficiently.
An aircraft with handling qualities which make it unlikely to recover a stall isn't suitable for passenger transport.
A stall as encountered by AF447 is a stable flight condition outside its authorised operating envelope, perfectly recoverable in airworthy passenger transports, and far from the second stage of PSG (post stall gyrations) and later, third, stabilized spin. Both later conditions may be unrecoverable in certain types and conditions.
I have flown with and without AOA indicators. They don't replace airmanship and flying skills.

[RetiredF4]

AOA indicator

opherben

I have flown with and without AOA indicators. They don't replace airmanship and flying skills.

Computers and all other stuff built in to modern FBW aircraft don´t either, but they are deemed necessary anyway. Because they help and assist to implement airamship and flying skills, as an AOA indicator would do as well.

Otherwise we could argue about what is really necessary besides airmanship and flying skills:
A cup of coffee: When the coffee leaves the cup, you are flying upside down.
And a cigar: When it is finished, it´s time to land.

[Machinbird]

An aircraft with handling qualities which make it unlikely to recover a stall isn't suitable for passenger transport.

Part of the AF447 crew problem that night must have been stall recognition. The flying qualities in the stall were too much like normal flight. Should that be a certification issue?

What about the "stall stall stall" warning you say? Unfortunately that occurred in a context where its validity was called into question. That is why AOA indicators could have helped.

I have flown with and without AOA indicators. They don't replace airmanship and flying skills.

Did you use your AOA as you flew, or did you consider it redundant?
When the airspeed packs up and anytime you are flying slowly, it can tell you quite a lot about your aircraft's performance potential.

Were your airmanship and flying skills as good at 0200 in the morning as they were at 1000 in the morning? If you had been in one of the front office seats in AF447 when the airspeed went South, are you certain it would have been a non-event for you?

[Mr Optimistic]

If the stall warning operates off aoa sensors, and you are in the mode not to believe the warning, why would you believe the aoa readout ? Can see it could potentially help, especially in recovery with uas, but otherwise what evidence is there that it would have helped the SA here ?

[aterpster]

[RWA]

Harryman

Why are the many training bodies not addressing recovery from stalls (of all styles and reasons), rather than simply illustrating their avoidance and prevention.

Excellent point, Harryman, IMO. My guess is that it's almost impossible for the programmers (however talented) to 'reproduce' stalls in a simulator; and equally impossible for the trainers (and the accountants) ever to let novice pilots actually stall real airliners worth hundreds of millions of dollars as part of their training..........

Any of us who have learned to fly anything have learned to 'deal with' stalls. But only in basic training (in my case in the odd Cessna and Blanek or T21 gliders). AND with the benefit of good visibility and instruments that were all working.

I doubt (well, just about KNOW) that any such practice would have been unlikely to have been of much help to the unfortunate guys flying AF447; in icing conditions, with at least periodically-malfunctioning instruments, zero visibility, and severe turbulence. AND with pre-programmed 'systems' interfering as well, though some at least of them will have been 'signing off' and 'leaving it to you' in the middle of things, and just sending you a useless 'encoded' message that the PNF just had to waste time reading and cancelling........

So I'm reasonably sure in my own mind what the accumulating 'problem(s)' that caused the accident were.

But I have no idea at ALL as to what the manufacturers AND the airlines can DO about it. And, seems to me, THEY likely won't have much idea either, up to the present time........

[BOAC]

RWA and all the other boys and girls here - I'm sorry to bang on about this, but please stop MAKING THINGS UP!

Originally Posted by BEA Report

The level of turbulence increased slightly

- NB NOT 'Severe Turbulence' Please try to stick to the given facts - it only confuses the thread. Soon it becomes 'fact' eg - "why did they fly straight into a CB?".

[Machinbird]

If the stall warning operates off aoa sensors, and you are in the mode not to believe the warning, why would you believe the aoa readout ? Can see it could potentially help, especially in recovery with uas, but otherwise what evidence is there that it would have helped the SA here ?

Well, let us see how this could be laid out in the cockpit.

First you have Port side AOA going to LHS AOA indicator, then Stbd side AOA going to RHS AOA indicator. The indication should be on the PFD if possible, and should NOT be numeric, but instead should be a simulated analog needle or tape display.

Then if you hear the stall warning, you can see the indicator bouncing in the stall zone and check with the other side for the same indications. Hopefully it is designed so as to get your attention, such as a pulsing red color when your AOA is excessive. Since it is moving you know it isn't stuck. Then all you have to do is believe it. Apply nose down stick and observe AOA decrease. Keep AOA in a safe range. Apply power as necessary. You sure as heck know you aren't approaching Vmo.

If you slap the equipment in a cockpit and don't train people in its use, then it is a waste. I'm sure a creative sim instructor can figure out some excellent training exercises to help bring AOA into your scan.

[ChristiaanJ]

Of course, Concorde had an AoA and 'G' indicator...



To what extent it was included in the normal T scan is another question.....

[OK465]

My guess is that it's almost impossible for the programmers (however talented) to 'reproduce' stalls in a simulator;

Not being argumentative, but this is not quite correct.

Flight test data from stall testing, to the extent it was conducted, is incorporated in advanced Full Flight Simulators. These flight tests are obviously structured for some measure of safety, so that beyond a certain point where data collection is out-weighed by risk, any additional data used in simulation is predicted data from other sources.

Beyond the stall boundary there is still a certain amount of training value where simulator characteristics and response to pilot inputs is valid. The problem is you cannot necessarily tell where flight test data transitions to predicted or extrapolated data during a more extended encounter. And truthfully this has not been given any priority in regulatory evaluation requirements of individual simulators. You don't "down" a sim for something for which you have no experience or guidance for subjective evaluation or a flight validated QTG for an automated evaluation.

The big jets are stalled and recovered so as to produce stall warning system functionality and tolerances and recommended avoidance and recovery procedures and technique. Simulations don't discount this.

As has been stated previously, however, improper pilot inputs to any simulation can also take you out of the realm of what was tested and into "new territory".

The advantage of simulation, of course, is that pilots can make improper inputs and get negative feedback safely. There is currently a lot of effort being directed at substantially improving jet transport stall simulations and incorporation into operator training.

[EGMA]

If the AoA is being monitored by the 'system' why not include it as part of any related 'aural'.

I don't need to continuously monitor an AoA indication but ...

"Stall warning 10, Stall warning 20, Stall warning 30, Stall warning 40"

... would sure get my attention ...

and ...

"Stall warning 30, Stall warning 20, Stall warning 10"

... just might let me know that ND was having an effect.

[HazelNuts39]

Originally Posted by Machinbird

Then if you hear the stall warning, you can see the indicator bouncing in the stall zone ...

When you're flying at Mach 0.6, and have lost your airspeeds, how do you know where your stall zone is on the AoA indicator?

[OK465]

If there is NO AOA indicator in the cockpit, it is NEVER available.

[Mr Optimistic]

I drink gin and tonics in the back. Give it up boys, an aoa monitor would have made no difference here.