Anyone understand if the readings fully came back? If so why wouldn’t the plane go back to normal law?
The crash of Air France flight 447 (2021)
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Re: The crash of Air France flight 447 (2021)
#72This brings up an interesting question: If the control was fully automated, the computer entirely in charged, would this have happened?
Re: The crash of Air France flight 447 (2021)
#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. Normal law also comes with full flight envelope protections in roll, pitch, speed, and load factor.
> If sensor failures occur, the controls drop down a level to “alternate law.” This law contains several sub-laws with slightly different configurations, but in general, alternate law means that some or all computer moderation of control inputs remains, but flight envelope protections are removed. The autopilot and auto thrust cease to function.
> In the event of further failures, the controls can enter direct law, in which there are no flight envelope protections and side stick inputs correspond directly to the position of the control surfaces, with no adjustment by the computer. This makes the airplane fly rather like a classic airliner, similar to most older Boeing models.
When you think of all of the Tesla accidents, this still seems to be the failure mode for autonomous systems. It's safer 95% of the time. But when it fails, it's because the users are so dependent on the systems that they don't even have the simplest of skills to prevent catastrophe.
Re: The crash of Air France flight 447 (2021)
#74> 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…
> it's because the users are so dependent on the systems that they don't even have the simplest of skills to prevent catastrophe.
One pilot was pushing full nose down. The other full nose up. The system _did_ tell them that they were doing this, but in the sea of other alarms, it didn't register with them.
The lack of alarm prioritization and the lack of crew resource management training in the face of an emergency seem like the major human factors here. Half of that is in the design of the plane, the other half in how the company trains their pilots to handle severe emergencies.
Re: The crash of Air France flight 447 (2021)
#75> 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.
Re: The crash of Air France flight 447 (2021)
#76It's tempting to blame the inexperienced first officers, their training, or the CRM failures on this flight, but the blame for this crash has to land squarely on the atrociously bad UX of the Airbus cockpit. Sensory overload and no clear readout of what is actually broken (pitot tube icing in this case) is bad but the fly-by-wire joystick configuration is what really doomed this flight. In Boeing airliners and many o…
* The overhead panel would've shown FAULT on the ADIRs. * The ECAM did show IF SPD DISAGREE: ADR CHECK PROC. * The plane did shout DUAL INPUT several times, and a button to lock out the other pilot is right on the stick. You can hear it being used by Bonin. I'd say this is a failure of lack of crew resource management (not even technical ability) more than anything else.
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Re: The crash of Air France flight 447 (2021)
#77It's tempting to blame the inexperienced first officers, their training, or the CRM failures on this flight, but the blame for this crash has to land squarely on the atrociously bad UX of the Airbus cockpit. Sensory overload and no clear readout of what is actually broken (pitot tube icing in this case) is bad but the fly-by-wire joystick configuration is what really doomed this flight. In Boeing airliners and many o…
> It's tempting to blame the inexperienced first officers or their training but the blame for this crash has to land squarely on the atrociously bad UX of the Airbus cockpit. The real problem is that someone who doesn't look at his most critical instrument* in instrument flying conditions, causes a stall, doesn't respond to stall warnings, doesn't communicate, refuses to hand over controls even though he doesn't unde…
Honestly, part of the mistake is also on Dubois. When flying as a team, it is essential to establish hierarchy and make sure who has authority. As the one with the lesser number of hours, Bonin should have been relegated in favor of Robert. That being said, hierarchy should not be as much of an obstacle that the one in authority disregards the suggestions of the copilot.
Re: The crash of Air France flight 447 (2021)
#78Earlier quoted context omitted.
The most likely thing to help in something like this, is for the plane to realize it's going to die, and just take over. And that has usually been the "airbus way", whereas Boeing has more had a notion of throw things to the pilots often enough so they know what they're doing.
The plane can't take over when it has no idea of what it's airspeed is. That's what caused this whole chain of problems in the first place.
We expect human pilots to be able to stop the plane from crashing when the airspeed is unknown. If that’s possible for humans, why not for computers?
Re: The crash of Air France flight 447 (2021)
#79Earlier quoted context omitted.
> But lack of sleep is a real issue. Even more on the US side since rest rules are worse than European. Somehow it doesn't get the attention it deserves. IMO this is almost a cultural issue. We don't prioritize sleep as much as we should and even hold lack of sleep as something to be idolized (i.e. sleep = laziness). How many times do we hear about those CEOs or Founders that wake up super early after only 5 hours of…
A side topic, I'm aghasted to know that preschool and primary schools start at 7:40. God it's going to be tough for my son who refuses to sleep before 10pm.
I think its well established that young children need at least 11-12 hours of sleep a night (depending on age). That would mean bedtime (or asleep by) 6:30pm the night before. These natural requirements don't fit well with societal norms.
I've noticed huge changes in my mood and the mood of my children when we get enough sleep. In my experience their meltdowns/tantrums (and mine as an adult) are either related to lack of sleep or hunger.
Sleep deprivation is a real problem that many may not realize until they get into the rhythm of healthy sleep.
Re: The crash of Air France flight 447 (2021)
#80I 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…
To be fair, it sounds like this crash caused airlines and regulators to demand much more adverse event training, including high-altitude stall recovery. But according to the article, Airbus hasn't addressed the split control issue…
There isn't a "split control issue," the split control setup is fundamental to the way the Airbus control schema works. Changing it would be a non-starter.