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The crash of Air France flight 447 (2021)

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Re: The crash of Air France flight 447 (2021)

#191

Post by this_steve_j »

This was quite a big mess! Let’s see if there is a way to break it down in a Safety II fashion.

1. Airline human resources deviated from the traditional practice of hiring experienced rudder and stick pilots.

1. Overly permissive company attitudes toward crew rest and a lack of awareness about how it can affect vigilance and fitness for duty.

1. Breakdown of the ceremonies that transfer command and control in the cockpit.

1. Lack of training for high altitude stall recovery.

1. Activities performed in low altitude stall recovery training scenarios are orthogonal to a successful recovery in high altitude stall scenarios.

1. Automation surprise followed by alert saturation combined with incongruous perceptual signals and loss of situational awareness.

1. Aircraft control systems that failed to resolve the ambiguous delegation of authority (double PF) dilemma.

1. Highly compressed timeline of events in a physically disorienting environment.

1. What else?

Re: The crash of Air France flight 447 (2021)

#192

Post by eep_social »

I love what the author is doing but I honestly don’t understand the gushing over their writing style. To me, it feels full of speculation and melodrama, exactly the language investigators don’t use when they write the accident reports:

> pilots into a state of paralyzed agitation..

> all the while trying desperately to understand..

> But there is a reason, written between the lines of the cockpit voice recorder transcript, hidden away within the mysterious code that governs human behavior, a key to the secrets of the profoundly irrational. Its lessons could not be more important, even for those who believe themselves above the doomed crew of flight 447, as the boundary between the responsibilities of man and machine grows ever dimmer.

> Overwhelmed by the noise of the warnings, the terrifying vibrations, and the wildly fluctuating instrument readings, his brain seemed to shut down, paralyzed by confusion and fear.

Citations needed.

Re: The crash of Air France flight 447 (2021)

#193

Post by mardifoufs »

logifail wrote: post #170
turnsout wrote: post #165

Earlier quoted context omitted.

In the case of 447, they were warned about a stall, repeatedly.

> In the case of 447, they were warned about a stall, repeatedly It's not that simple. When the aircraft's computer considered the inputs invalid, the stall warning was muted . When they decreased the pitch (would be essential to recover from the stall!) the stall warning sounded . "The angle of attack had then reached 40°, and the aircraft had descended to 35,000 feet (10,668 m) with the engines running at almost 10…

Jesus Christ what a terrifying situation. I read about this over and over again and it's still mind boggling how multiple systems and "exceptions" collided resulting in the worst scenario possible. I know the pilots are also to "blame" in a way, but man... The safety systems sure do have a lot of obscure modes and different ways to handle error and failures...

Re: The crash of Air France flight 447 (2021)

#194

Post by 7952 »

psunavy03 wrote: post #46

I fly a desk herding cats, I mean devs, for a living now. But as a Navy-trained aviator, this and the Colgan Air mishap in Buffalo always make me cringe. I can't entirely judge the crew, because the human mind is a strange thing that has ways of rationalizing truly abnormal situations and behavior. That said, an obvious Crew Resource Management failure compounded the issues here. That said, I believe aerobatics and o…

Although they were not just hand flying. They were hand flying at a moments notice in IMC with faulty instrument data in a highly complex system. That combination of factors does seem to be a huge risk factor for accidents.

I wonder if reverting back to pilot control is really the best approach in situations with faulty instruments. Perhaps it would be safer to use algorithms that can deal with bad data in a sane way. A middle ground between blindly trusting bad data (as in 737 max) and reverting to the pilot. Use other data like GPS, accelerometers, strain sensors ,fuel flow rate sensors, to sense check the primary instruments.

Re: The crash of Air France flight 447 (2021)

#195

Post by mardifoufs »

_cenw wrote: post #75
legitster wrote: post #73

> Behind the scenes, the loss of valid airspeed data had triggered a shift in the Airbus’s complex flight control laws. In “normal law,” computers interpret pilots’ side stick inputs and move the control surfaces in accordance with what is reasonable at that altitude, speed, and configuration. This improves the handling of the airplane to such an extent that no particular skill is required to fly it gracefully. Norma…

I'd be hesitant to compare these. The aircraft still operated as designed. It detected that the input data was bad and turned the automation off. The pilot flying just didn't seem to grasp what that means. Most Tesla Autopilot failures aren't drivers that don't know how to drive, it's the automation making bad inputs.

No, some warnings were also thrown away and never shown to the pilots because the automated systems thought they were erroneous (since they were so outside the flight envelope IIRC).

Re: The crash of Air France flight 447 (2021)

#196

Post by [deleted] »

psunavy03 wrote: post #46

I fly a desk herding cats, I mean devs, for a living now. But as a Navy-trained aviator, this and the Colgan Air mishap in Buffalo always make me cringe. I can't entirely judge the crew, because the human mind is a strange thing that has ways of rationalizing truly abnormal situations and behavior. That said, an obvious Crew Resource Management failure compounded the issues here. That said, I believe aerobatics and o…

[deleted]

Re: The crash of Air France flight 447 (2021)

#197

Post by batiste »

Tronno wrote: post #98

In post-mortems involving pilot error, what strikes me is that airliner cockpit design sounds so convoluted, unintuitive, and just plain bad . The burden of disentangling this bad design is always placed on the pilots - through extensive training and rote memorization - which inevitably fails under stress. In this particular example, consider: - the opposing pilot inputs being signaled only by a pair of little green…

There should be a calm AI voice stating what they should be doing based on some heuristics. Based on angle of attack, engine power and the last recorded reliable speed, I feel a simple system should be able to make projection of the current speed and throw some warning when pilot input are becoming real stupid.

Re: The crash of Air France flight 447 (2021)

#198

Post by polynomial »

psunavy03 wrote: post #46

I fly a desk herding cats, I mean devs, for a living now. But as a Navy-trained aviator, this and the Colgan Air mishap in Buffalo always make me cringe. I can't entirely judge the crew, because the human mind is a strange thing that has ways of rationalizing truly abnormal situations and behavior. That said, an obvious Crew Resource Management failure compounded the issues here. That said, I believe aerobatics and o…

It is profoundly disturbing, but we do live in an age where everything is simulated, including expertise. How much time did Captain Dubois have to save the aircraft once he was on deck? Seems like Bolin had mostly doomed them by then.

Re: The crash of Air France flight 447 (2021)

#199

Post by davidktr »

rich_sasha wrote: post #182

As someone who follows aviation and flew the Flight Simulator quite a bit when young, I don't quite understand how it all happened. The mechanics are clear, but aren't pilots trained _ad nauseam_ precisely against this kind of events? It read like this was two panicking guys shouting at each other. By contrast, listening to the recording of the Hudson River landing, it was stunning just how eerily calm the pilots was…

If you have an hour to spare, I found this video by an experienced pilot extremely helpful: https://www.youtube.com/watch?v=e5AGHEUxLME

Re: The crash of Air France flight 447 (2021)

#200

Post by matheusmoreira »

rsync wrote: post #7

Perhaps these pilots were "Children of the Magenta"[1] ? These AA instructional videos by Captain Vanderburgh are fascinating - even to a non-pilot like myself. They are especially relevant as we dip our toes into automobile auto-pilot and the "automation dependency" that comes along with it. Of particular note in this video: @ 12:30: "... tactily connected to the airplane ..." @ 14:15: "... we see automation depende…

Autopilot, automation, algorithms, safeties, guarantees, envelopes... Illusions, gone at the first sign of trouble. I easily get used to such technological comforts and it is deeply traumatizing when they're talking away.

The badassery men are capable of when they accept this and drive instead of allowing themselves to be driven is the stuff of legends.

https://en.wikipedia.org/wiki/Mercury-Atlas_9

https://en.wikipedia.org/wiki/Gordon_Cooper

> Cooper lost all attitude readings.

> [a short-circuit] left the automatic stabilization and control system without electric power.

> Cooper noted that the carbon dioxide level was rising in the cabin and in his spacesuit.

> "Things are beginning to stack up a little."

> Turning to his understanding of star patterns, Cooper took manual control of the tiny capsule and successfully estimated the correct pitch for re-entry into the atmosphere.

> Cooper drew lines on the capsule window to help him check his orientation before firing the re-entry rockets.

> "So I used my wrist watch for time," he later recalled, "my eyeballs out the window for attitude."

> "Then I fired my retrorockets at the right time and landed right by the carrier."

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