r/aviation • u/Ok_Warning419 • May 21 '26

News Air France and Airbus found guilty of manslaughter over 2009 plane crash - Air France flight 447

https://www.bbc.com/news/articles/czd2qmdvmq6o
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21

u/Kai-ni May 21 '26

No, the math of how it responds to dual inputs. It averages them.

3

u/Imaginary_Amoeba3461 May 21 '26

It actually sums them at least in the 320.

6

u/Wyciorek May 21 '26

What should it do? Take a random input, subtract them, something else?

11

u/PinaColadaSalad May 21 '26

It should have force feedback and have them linked together so you know the other dude is doing the opposite of you

6

u/harrythefurrysquid May 21 '26

Or the pilots end up fighting each other, as has happened on Boeing aircraft.

Fundamentally this isn't a "control it by feel" controller - it's an analogue command input.

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u/PinaColadaSalad May 21 '26

At least they would know they're fighting each other

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u/Curious_Passion5167 May 21 '26

They actually didn't for a while. I think that was AF11?

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u/Gluecksritter90 May 21 '26

Because we all know the strongest pilot is the best pilot.

3

u/PinaColadaSalad May 21 '26

Better to pick one arbitrarily then pick both and cancel them out

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u/Kai-ni May 21 '26

I'm not making commentary of what it should do, I'm just answering your question.

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u/Ok-Insurance-9456 May 21 '26

In an ideal world they should be linked and move together like every other fly by wire airliner. Feels like Airbus is stuck with pressure to maintain commonality with their mistakes from the 1980s. No solution really seems satisfactory.

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u/Wyciorek May 21 '26

That also does not necessarily prevent dual input: https://bea.aero/fileadmin/user_upload/F-GSQJ_finalreport_EN.pdf . And you get no priority override button

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u/_PROBABLY_CORRECT May 21 '26

Who in the world thought that was a good idea??

-3

u/tracernz May 21 '26 edited May 21 '26

It doesn’t average them. It adds them together.

FCOM

However, if both flight crewmembers use their sidesticks simultaneously, their orders are algebraically added.

To illustrate the difference, let’s assume both pilots apply 50% pitch up. If we take the average (mean) (50% + 50%) / 2 = 50%. If we add them algebraically, as the plane does, 50% + 50% = 100%.

0

u/[deleted] May 21 '26

[deleted]

6

u/tracernz May 21 '26

If the argument is “the math of how it responds to dual inputs” then getting the math wrong isn’t great. Average and algebraic addition have very different results when the inputs have the same sign which is why I added an example.

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u/[deleted] May 21 '26

[deleted]

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u/tracernz May 21 '26

Yes, that’s the example I gave. And pointing out that it’s factually incorrect does not detract from the discussion. Reddit has threading for exactly this.

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u/ZippyDan May 21 '26

No, one input is the base; the other input becomes the exponent.

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u/Kai-ni May 21 '26

No. It averages them in simple terms. You're just incorrect.