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I don't want to minimize pilot errors but I can't stop thinking this dual inputs system easily ranks in the top 5 of the worst design ideas in history. Probabl

I don't want to minimize pilot errors but I can't stop thinking this dual inputs system easily ranks in the top 5 of the worst design ideas in history. Probably just behind the MCAS.

lbourdages 3y ago
Is there really an alternative? Say one pilot loses consciousness, the other one has to extract them from their seat before they can fly the airplane. That's no easy task - humans are surprisingly heavy once they pass out.
- voxadam 3y ago
  Three pilots with a voting algo, obviously. Or, maybe, a supreme court of nine pilots all constantly and continuously in search of perfect aerodynamic justice. Ah hell, just let ChatGPT fly the damn plane. Edit: I've got it! We'll have a single pilot but they'll be based on a Rust rewrite of ChatGPT running on RISC-V.
  - winchester6788 3y ago
    2 chatgpt instances controlling the dual inputs would be funny
- skylabmelody 3y ago
  By "dual input system" I was referring to the fact that both pilots can apply input into their sticks or trim wheels simultaneously resulting into inputs cancelling each other out or de-synchronizing.
  - lbourdages 3y ago
    Agreed, that seems like a really bad design. At the very least there should be an alert whenever the system detects that both pilots are touching the controls.
- masklinn 3y ago
  Airbus has had a Priority Takeover button, from the start, I assume Boeing also has something like that. Its primary use case is exactly what you’re talking about, although it also disables autopilot so it’s a good way to ensure you have manual input in case you need to react quickly. Airbus has a dual input alert, apparently Boeing doesn’t, and didn’t add it after this incident, blows my mind. Still they’re far from perfect, stress deafness is absolutely a thing. Active sticks (force feedback) are finally making it into commercial cockpits, they’ve been deployed in business jets, and the Irkut MC-21 was supposed to be the first implementation in an airliner (as it’s french-made, that’s been sunk by the Russian invasion of Ukraine and subsequent economic blockade). This means hopefully active stick swill make it into big two airframes eventually. I assume there’s some redesign work ongoing as it likely requires additional power and data connection, AFAIK currently the sticks (Airbus’s anyway) are just centered and resisting via springs, I don’t think there’s any data fed back into the sticks.
  - skylabmelody 3y ago
    Quite incredible that the aviation industry haven't introduces sticks with force-feedback despite video game industry having them for about 30 years. Probably because it's a patent lawsuit minefield.
    - sph 3y ago
      They have vibration in case of imminent stall: https://en.wikipedia.org/wiki/Stick_shaker https://en.wikipedia.org/wiki/Stick_shaker
    - scrlk 3y ago
      Active sidesticks have been around for a few years now: https://www.youtube.com/watch?v=3sXXx8rgeeE https://www.youtube.com/watch?v=3sXXx8rgeeE
    - masklinn 3y ago
      Active sticks have been in development for decades. They’re getting deployed on civilian crafts these days e.g. Gulf Stream’s top of the lines jets (though retrofitting them on existing planes is likely a ways away still). I would assume the issues are / were around reliability, failure modes, certification and training rather than patents.
- gray_-_wolf 3y ago
  Hm, cannot you just have a tree-way switch determining the active control (both, A only, B only)?
goodcanadian 3y ago
I always hate findings of "pilot error." Like you, I don't want to minimise it, but it never feels like it gets to the root cause. It often feels a bit like scapegoating. Why did highly trained, presumably competent pilots make the error? How can it be avoided in the future? As you say, UI design choices can make errors more or less likely. Absolutely everyone makes mistakes. We need to design to reduce the likelihood of mistakes and to minimise the impact of mistakes when they do happen. To be clear, I think everyone in the industry understands this, but when reported in the media, the average public just hears, "Pilots f'ed up," which is almost never a complete picture.
- Dalewyn 3y ago
  Sometimes it really does come down to sheer stupidity or incompetence. Taking the recent incident at HND earlier this month between a JAL A350 and JCG DHC-8, the investigation (currently still ongoing) is pointing to the JCG Captain astronomically fucking up: * ATC ordered the JCG DHC-8 to hold short of the runway and informed them they were #1 in the take off queue. Take off clearance was never given. * The First Officer of the JCG DHC-8 read back the order to hold short and their position in the queue. * JAL A350 had clearance to land and (along with other aircraft) listened in to the above conversation, routine stuff to help maintain situational awareness. * The Captain of the JCG DHC-8 entered the runway, violating order to hold short, and sat there for approximately 40 seconds until they were struck by the JAL A350. ATC, JAL, and even the JCG First Officer all did things right and yet all it took was apparently one Captain screwing up. Yes, there were compounding factors like how it was nighttime and all the airport lights flooded out the JCG DHC-8's lights, but pilot error is the only reasonable way of ultimately explaining incidents like this.
  - goodcanadian 3y ago
    So, I would say that pilot error is a primary factor in this case. But, that still leaves open the question of why the error occurred and whether there is anything we can do to reduce the probability of it happening again. I highly doubt the Captain is simply stupid or incompetent given all of his experience. Perhaps, the crew was overly fatigued? People make mistakes, sometimes big ones. The question is how to reduce mistakes and how to limit damage from those mistakes.
Havoc 3y ago
Yes especially the fact that they can drift in and out of sync. How are the pilots even supposed to know what the resulting net input is?
- kube-system 3y ago
  There should never be a 'net' input. Only one pilot can fly a plane at a time. This is fundamental training for pilots, they would have learned this in the very first few moments they sat behind the controls.
WalterBright 3y ago
Dual inputs is there for redundancy in case of a jam in one of them, or in case one set of cables is cut. Everything is dual. The reason pilots are there is to diagnose problems and take the right corrective action. This also means they can misdiagnose problems and take the wrong action. This is where pilot training comes in.

I don't want to minimize pilot errors but I can't stop thinking this dual inputs system easily ranks in the top 5 of the worst design ideas in history. Probably just behind the MCAS.

lbourdages 3y ago

Is there really an alternative? Say one pilot loses consciousness, the other one has to extract them from their seat before they can fly the airplane. That's no easy task - humans are surprisingly heavy once they pass out.

voxadam 3y ago
Three pilots with a voting algo, obviously. Or, maybe, a supreme court of nine pilots all constantly and continuously in search of perfect aerodynamic justice. Ah hell, just let ChatGPT fly the damn plane. Edit: I've got it! We'll have a single pilot but they'll be based on a Rust rewrite of ChatGPT running on RISC-V.
- winchester6788 3y ago
  2 chatgpt instances controlling the dual inputs would be funny
skylabmelody 3y ago
By "dual input system" I was referring to the fact that both pilots can apply input into their sticks or trim wheels simultaneously resulting into inputs cancelling each other out or de-synchronizing.
- lbourdages 3y ago
  Agreed, that seems like a really bad design. At the very least there should be an alert whenever the system detects that both pilots are touching the controls.
masklinn 3y ago
Airbus has had a Priority Takeover button, from the start, I assume Boeing also has something like that. Its primary use case is exactly what you’re talking about, although it also disables autopilot so it’s a good way to ensure you have manual input in case you need to react quickly. Airbus has a dual input alert, apparently Boeing doesn’t, and didn’t add it after this incident, blows my mind. Still they’re far from perfect, stress deafness is absolutely a thing. Active sticks (force feedback) are finally making it into commercial cockpits, they’ve been deployed in business jets, and the Irkut MC-21 was supposed to be the first implementation in an airliner (as it’s french-made, that’s been sunk by the Russian invasion of Ukraine and subsequent economic blockade). This means hopefully active stick swill make it into big two airframes eventually. I assume there’s some redesign work ongoing as it likely requires additional power and data connection, AFAIK currently the sticks (Airbus’s anyway) are just centered and resisting via springs, I don’t think there’s any data fed back into the sticks.
- skylabmelody 3y ago
  Quite incredible that the aviation industry haven't introduces sticks with force-feedback despite video game industry having them for about 30 years. Probably because it's a patent lawsuit minefield.
  - sph 3y ago
    They have vibration in case of imminent stall: https://en.wikipedia.org/wiki/Stick_shaker https://en.wikipedia.org/wiki/Stick_shaker
  - scrlk 3y ago
    Active sidesticks have been around for a few years now: https://www.youtube.com/watch?v=3sXXx8rgeeE https://www.youtube.com/watch?v=3sXXx8rgeeE
  - masklinn 3y ago
    Active sticks have been in development for decades. They’re getting deployed on civilian crafts these days e.g. Gulf Stream’s top of the lines jets (though retrofitting them on existing planes is likely a ways away still). I would assume the issues are / were around reliability, failure modes, certification and training rather than patents.
gray_-_wolf 3y ago
Hm, cannot you just have a tree-way switch determining the active control (both, A only, B only)?

goodcanadian 3y ago

I always hate findings of "pilot error." Like you, I don't want to minimise it, but it never feels like it gets to the root cause. It often feels a bit like scapegoating. Why did highly trained, presumably competent pilots make the error? How can it be avoided in the future? As you say, UI design choices can make errors more or less likely. Absolutely everyone makes mistakes. We need to design to reduce the likelihood of mistakes and to minimise the impact of mistakes when they do happen. To be clear, I think everyone in the industry understands this, but when reported in the media, the average public just hears, "Pilots f'ed up," which is almost never a complete picture.

Dalewyn 3y ago
Sometimes it really does come down to sheer stupidity or incompetence. Taking the recent incident at HND earlier this month between a JAL A350 and JCG DHC-8, the investigation (currently still ongoing) is pointing to the JCG Captain astronomically fucking up: * ATC ordered the JCG DHC-8 to hold short of the runway and informed them they were #1 in the take off queue. Take off clearance was never given. * The First Officer of the JCG DHC-8 read back the order to hold short and their position in the queue. * JAL A350 had clearance to land and (along with other aircraft) listened in to the above conversation, routine stuff to help maintain situational awareness. * The Captain of the JCG DHC-8 entered the runway, violating order to hold short, and sat there for approximately 40 seconds until they were struck by the JAL A350. ATC, JAL, and even the JCG First Officer all did things right and yet all it took was apparently one Captain screwing up. Yes, there were compounding factors like how it was nighttime and all the airport lights flooded out the JCG DHC-8's lights, but pilot error is the only reasonable way of ultimately explaining incidents like this.
- goodcanadian 3y ago
  So, I would say that pilot error is a primary factor in this case. But, that still leaves open the question of why the error occurred and whether there is anything we can do to reduce the probability of it happening again. I highly doubt the Captain is simply stupid or incompetent given all of his experience. Perhaps, the crew was overly fatigued? People make mistakes, sometimes big ones. The question is how to reduce mistakes and how to limit damage from those mistakes.

Havoc 3y ago

Yes especially the fact that they can drift in and out of sync. How are the pilots even supposed to know what the resulting net input is?

kube-system 3y ago
There should never be a 'net' input. Only one pilot can fly a plane at a time. This is fundamental training for pilots, they would have learned this in the very first few moments they sat behind the controls.

WalterBright 3y ago

Dual inputs is there for redundancy in case of a jam in one of them, or in case one set of cables is cut. Everything is dual. The reason pilots are there is to diagnose problems and take the right corrective action. This also means they can misdiagnose problems and take the wrong action. This is where pilot training comes in.