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[Evan]

True, but only Airbus planes can be the focus of ominous conspiracies in scarebus 'documentaries'....

[Evan]

Did they know about it 30 years ago? I am aware that the problem most notably occurred in flight in June 2012 on a JetBlue A320, and that Airbus had been aware of other incidents prior to that and had issued SB's about the risk around 2007. I'm unclear as to when the problem actually first revealed itself.

I'm curious as to how this resulted in a sim crash however. You would still have the blue system, so loss of control doesn't add up. You would be in hand-flying in Alternate Law however, with no hard protections. You would have lost roll spoilers and the THS trim. You would lose flaps but not slats. The gear in your scenario, I assume, would still be extended (as in most cases of this scenario as the fault occurs in the gear retraction hydraulics) and if not, there's alternate gear extension. The only thing that fits my understanding would be pilot error without envelope protections. Or a runway overrun if the runway is short. While it was seriously concerning, I didn't...

[Evan]

Dual hydraulics loss due to PTU overheat? They did fix this by altering logic with PTU automatically switching off below 1500ft.

https://safetyfirst.airbus.com/app/t...aulic-loss.pdf...

[Evan]

I totally agree with that. There's no reason why pilots need to understand the complexities of C* so long as they have the proper training to fly the airplane. How many 737 pilots can explain the complexities of the elevator artificial feedback system? It's much more important that they understand advanced aerodynamics and the philosophy and rules of stable approach criteria. The 15deg/sec roll rate limit is for Normal Law, but you should have 30deg/sec during critical Direct Law phases. I'm not sure what you mean by 'roll stops' but with a 33deg soft stop and a 67deg hard stop, I'm not sure what sort of maneuvering you are attempting with a passenger transport aircraft. I admit that, if you need to thread the tight mountainous approaches of rural Nepal, there are better choices for aircraft....

[Evan]

Well, Concorde had a rudimentary form of FBW but what we are really discussing is the C* aspect, control laws using load factor and pitch rate with auto-stability and envelope protections. Both Airbus and Boeing incorporate C* logic (Boeing uses C*U, using a reference speed adjusted by a mock trim switch). C* has roots in NASA experimental work with modified F-8’s that eventually led to the F-16. I think skeptics of the Airbus FBW should read more deeply into the development history, as it would make them less dubious of the thought that went into it. Development and certification of the A320 required an enormous amount of scrutiny and redundancy requirements from the certification authorities.

One key requirement comes from Part 25 of the FAA requirement for static longitudinal stability. Without flight envelope protections, C* would not meet those requirements (C*U can meet them with soft protections due to the artificial stability provided by the reference speed aspect...

[Evan]

What Airbus set out to do (and did) was to incorporate technological advances from the space program in ways that made a lighter, safer, less workload-intensive aircraft. Fly-by-wire did away with heavy rigging and allowed for C* flight control laws that would fly more accurately and efficiently and make the protected airliner possible. They did away with the chore of trim, replacing the absence of force feedback with hard envelope protections. That was the main advancement. Sidestick FBW aviation has since expanded to many types or aircraft. Because its the future of aviation.

They did not set out to create a fool-proof airliner. Fool-resistant perhaps. The technical and airmanship knowledge to get a type-rating, as you know, is not "piloting for dummies". Many fools have crashed it, including veteran Boeing pilots who considered themselves to be no fools. They also realized that there would be circumstances where the flight control protections would not be available,...

[Evan]

Do tell....

[Evan]

I'm questioning your grasp of logic itself. MCAS initiated the upsets, the precarious and ultimately fatal situation, not the pilots themselves. No avionic system can be allowed to cause an upset, because an upset can lead to pilot error, as it has in countless tragedies. No system can subsequently be that dependent upon reliable pilot counter-actions under stress, disorientation, time compression, confirmation bias and tunneling that very often result from sudden upsets. Furthermore, the system that caused that upset, MCAS, had no redundancy for a single point of failure. That is entirely unacceptable.

None of that is true of weaknesses in Airbus logic, with the extremely rare and transient exception of the Qantas flt 72 and 71 issue I previously mentioned, which were caused by unforseeable phenomena and quickly resolved with software updates. There was no cover up or denial involved.

This 'documentary' is predictable sensationalist nonsense assembled by a general...

[Evan]

bstolle, as a line pilot you certainly must be familiar with ‘confirmation bias’ the natural tendency to place more weight on things that align with your beliefs and expectations and less weight (or no weight) upon things that contradict them. Not only is this essential to embracing conspiracy theories, it is the structure upon which they are built. You wonder what Airbus might be ‘hiding’, what they might be trying to cover up, yet seem to overlook the fact that this pilot allowed the plane to get into a dangerously low energy state and broke way below his flight plan minimums, getting down to 32ft at maximum AoA with obstacles in the runway extended centerline at critically low airspeed. No safety culture would allow that. Because that is not flying the plane. That is not aviating.

No airplane is perfect and this one did not save him from crashing (nor did it work against him). But it did save his life and the lives of many of his passengers.
...

[Evan]

Update: I got all the way to 14:30. "After V1, there is no way to stop." I could go no further. Save yourself the experience Gabe.

You've got a conservative former Lufthansa technical pilot from the 80's with an obvious bone of contention about progress and FBW protections in particular (like many other of his era) talking about how "Airbus intends to eliminate the pilots". Herr van Beverin builds a film around this pilot's paranoid and obsolete delusions. The 'filmmaker' uses tactics like getting a current line pilot to 'admit' that he doesn't know the intricacies of how the A320 factors the 1-second reaction time delay into V1 calculation, and turns it into 'proof' that Airbus isn't telling pilots how the plane works. I could gather a room full of A320 pilots and ask them technical questions about the LGCIU logic and at least half would either give me a blank stare or get it wrong, and that doesn't bother me at all. Nor should it. If BoeingBobby doesn't...

[Evan]

A quote from the film regarding the crash we are discussing:

"Air France captain passes the field of an airshow too low. When he realized the altitude mistake, the plane did not accelerate, not did it climb as he commanded. The official cause of the accident (pregnant pause) pilot error."

That gives it away for me. The plane did not accelerate because it was coming up from extended flight idle, not due to any "fatal logic" and it did not climb because it could not climb at that speed without stalling and killing everyone on board. Fatal Logic?

I'll go the rest of it, but I suspect bstolle will owe me the 27 minutes of my life that was wasted....

[Evan]

No, Airbus has spoken. To pilots. Stable approach criteria. Stabilization gates. Go around-minded safety culture.

If you are touching down like they did, where they did and at the speed they did, I don't see where you get to criticize anything but yourselves.

Pilots aren't perfect. That's ok. Abandon the approach and try again. Don't say I got this and then blame the airplane when the hard reality steps in.

Planes aren't perfect either. But it is far better for them to error with reversers and ground spoilers on the ground than in the sky....

[Evan]

Airbus did get the film banned, for very good reason. Unfortunately we live in an age where certain enterprising charlatans seek opportunity in freedom of speech to profit from nonsense and paranoia. So it is now available again. If you enjoyed this, I would also recommend 9/11 was an inside job, flat earth society and RFK jr....

[Evan]

Did you forget the blue font Gabe?

Answer: it depends. If the film points out the fatal logic in continuing an unstable tailwind approach and touching down 2500ft past threshold at 170kts, then yes, it’s true. If the film deals in scarebus conspiracy, then what was I just saying about monkeys?...

[Evan]

And, for the record, there have been some notable incidents of pilots monkeying with the plane. Including some monkey see, monkey do. AIrbus did not include monkey-proofing in the design spec, regrettably....

[Evan]

Yes, but more to the point, Airbus estimates that any pilot who is granted a CTPL is reliably capable of getting down safely without Alpha Floor from 100ft (which assumes visual) in manual flight. Those protections are second line of defense intended for more stall-prone situations. It was not designed for level fly-by’s near Alpha Max below that threshold. It is not designed to be idiot-proof.

This accident flight came right to the edge of Flare mode, the 30ft threshold, where a nose down order is added by the computers, but fortunately remained just above it....

[Evan]

Oh, hang on... duh... Alpha Floor itself is inhibited below 100ft RA. So it wouldn't have saved them anyway....

[Evan]

Yes! With passengers on board?! Who approved that and how much prison time did they do?



I question that though. This pilot had complete confidence in the protected aircraft. Would he even have attempted this without those protections? Those protections are there as a second line of defense, not a first line of defense. But it seems that sometimes pilots miss that point and do things they would never do otherwise....

[Evan]

Still unclear is who's bright idea it was to disable Alpha Floor on a passenger flight. Capt. Assoline (sp?) did 10 months in prison for this, but the flight plan was approved beforehand. He was a 20-year technical pilot for Air France who had conducted test flights for the A320 and knew the systems well. But who approved the idea? Also unclear is why the low SPEED warning didn't sound at 1.03 VLS. Disconnected? Hard AoA protections without Alpha Floor or any sort of low speed warning is just asking for trouble. You DEFINITELY don't do this with pax aboard....

[Evan]

Because, as always, we discuss what might have happened (and why) and you focus on what should have happened based upon your Cessna proficiency....