[nknighthb]

Is it standard procedure to land A320s in the Hudson? Prior to 2009, how likely do you think it would have been for someone to have programmed an autopilot with such a capability?

Do pilots typically glide unpowered 767s to landings at abandoned military airfields? (A result, incidentally, that could not be reproduced by other crews in simulators; are you sure it's the crews, and not inadequate programming? Still trust the computer?)

Are you willing to bet your life that the computer on a 737 that looked like this[1] could find its way to a safe landing?

As programmers, we should know better.

[1] http://en.wikipedia.org/wiki/File:Aloha_Airlines_Flight_243_...

[lisper]

> Is it standard procedure to land A320s in the Hudson?

Yes, ditching an airplane that has lost all of its engines is a standard emergency procedure.

> Prior to 2009, how likely do you think it would have been for someone to have programmed an autopilot with such a capability?

What difference does that make? I'm not saying it's a good idea to take pilots out of the cockpit right now, I'm just saying it's a lot more plausible than most people think. The main limiting factor is politics, not technology.

> Are you willing to bet your life that the computer on a 737 that looked like this[1] could find its way to a safe landing?

Sure, why not? Losing the top of the fuselage looks dramatic, but it probably doesn't change the flight characteristics all that much. Also, very good adaptive control algorithms exist that could almost certainly handle this.

Also, you're cherry-picking your anecdotes. There are plenty of examples of flights that would almost certainly have ended safely but for some stupid mistake the pilot made. Controlled flight into terrain accidents, for example, are much more common than heroic rescues, and they could be entirely eliminated if you took human pilots out of the loop.

[nknighthb]

> Yes, ditching an airplane that has lost all of its engines is a standard emergency procedure.

See my reply to krisoft. You're changing a specific situation into a general one. You can't just say "ditch the plane if you lose power", you have to anticipate every possible variable that may influence whether that is actually the correct course of action, and the manner in which it is carried out. And you have to do that before it ever happens.

> What difference does that make?

Unanticipated situations are unanticipated situations. We don't have AI. We haven't replicated the ability of a human being to adapt on-the-fly. There is no reason to believe we will in the near future.

> Controlled flight into terrain accidents [...] could be entirely eliminated if you took human pilots out of the loop.

The problem I have with this line of reasoning is that so much more could be done to prevent them even without taking the pilots out of the loop, and yet it's not. That does nothing to give me confidence that the right thing will be done when pilots ARE taken out of the loop.

Edit: What it comes down to is this. All you're ultimately doing is completely and irrevocably substituting the unalterable judgement of somebody in a completely different time, place, and circumstance for the adaptable judgement of the person on the plane. When you do that, what you're really saying is "I refuse to give people in a scenario I didn't think about the chance to survive". I can't accept that.

[snom380]

CFIT used to be common, but it's not anymore on commercial flights thanks to GPWS. There's not yet been an accident on an airplane equipped with EGPWS.

[krisoft]

Emergency landing on water is "standard procedure". You might have the impression that it's something which was creatively invented by the pilot at a moments notice, but it's really not. The engineers designed the airplane with the capability, included advice and checklist in the operation manual, they even put a button labeled "ditch" on the dash! Can't really see why they could not make such an autopilot program.

[nknighthb]

You completely misunderstand. I wasn't talking about a generic "emergency landing on water".

A plane suddenly loses power in a highly urbanized area. It's very near multiple airports. Prior to 2009, I have no expectation that an autopilot would have been equipped to judge whether it should attempt to land in a heavily-trafficked river. (I further have no expectation that it would have been equipped to notice in the highly plausible scenario of one or more small boats being in the way.)

It's not a question of landing on water, it's a question of making the decision to do so and where.

Humans have the judgement gained by a lifetime of learning. Computers only have what it occurs to us to put into them while we're sitting safe and sound in our little offices pushing little buttons that don't threaten our lives.