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I think one easy example to think about is a landing configuration alarm. This usually sounds when the altitude is below a certain altitude (must be landing) bu

I think one easy example to think about is a landing configuration alarm. This usually sounds when the altitude is below a certain altitude (must be landing) but the flaps are up (or something else is not according to the handbook landing instructions). Could also be landing gear up but I think that was a common enough problem that newer commercial aircraft tend to have a dedicated "gear not down" alarm just for that case. It's a situation where there's a pretty clear action to be taken (extend flaps) but that change will meaningfully impact flight dynamics, will need application of elevators and changes to trim, etc. and so changing it without pilot input could be a real hazard. I think a lot of more subtle situations fall into the same category of there being a pretty clear corrective action, but the pilot needs to have positive awareness of when that change occurs, and may decide to delay action or do something else. We can pretty easily draw analogy to this kind of thing in computing. Database migrations are one I've run into - nice for them to be completely automated in routine situations, but because they can result in downtime or old versions not working in some cases it's a good idea to run migrations with an engineer "in the loop" for uptime critical software. If it's automated they click the button and do nothing, but having the button to click ensures that they're aware of the change and present in case of problems.

nucleardog 6y ago
I think you touch on what might be an easier example to demonstrate with here: "GEAR NOT DOWN" So the plane has determined you are close to the ground, but the landing gear is not extended. What is the proper course of action? If you're trying to land on a runway or other normal surface (i.e., 99 cases out of a hundred type of thing) the appropriate action would be to extend the landing gear. In that other case though, extending the landing gear in preparation for something like an emergency water landing is certain to take something which has a surprisingly good survival rate and turn it into a mass casualty event. So we're left with the choice between "do the usual thing automatically, and rely on the pilot to remember to override it in the rare event of an emergency" or "alert the pilot and rely on them to evaluate whether it's the right thing for their current situation and conditions". I would definitely argue for the latter. Especially in this specific example increasing cognitive load during exceptional situations to make the unexceptional more convenient is probably not what we want to do. The plane is not aware of the actual situation the plane is in. The pilot is.

nucleardog 6y ago

I think you touch on what might be an easier example to demonstrate with here: "GEAR NOT DOWN" So the plane has determined you are close to the ground, but the landing gear is not extended. What is the proper course of action? If you're trying to land on a runway or other normal surface (i.e., 99 cases out of a hundred type of thing) the appropriate action would be to extend the landing gear. In that other case though, extending the landing gear in preparation for something like an emergency water landing is certain to take something which has a surprisingly good survival rate and turn it into a mass casualty event. So we're left with the choice between "do the usual thing automatically, and rely on the pilot to remember to override it in the rare event of an emergency" or "alert the pilot and rely on them to evaluate whether it's the right thing for their current situation and conditions". I would definitely argue for the latter. Especially in this specific example increasing cognitive load during exceptional situations to make the unexceptional more convenient is probably not what we want to do. The plane is not aware of the actual situation the plane is in. The pilot is.