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Armchair air crash investigator

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Re: Armchair air crash investigator

#121

Post by nknighthb »

lisper wrote: post #119
nknighthb wrote: post #109

Earlier quoted context omitted.

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 tru…

> 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…

> 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.

Re: Armchair air crash investigator

#122

Post by fnordfnordfnord »

RockyMcNuts wrote: post #56
RockyMcNuts wrote: post #36

Earlier quoted context omitted.

like this link better than the OP which is fairly uninformed speculation ...

some video of the crash - kind of looks like it was skimming the waves in ground effect trying to go around http://www.cnn.com/video/?/video/us/2013/07/07/vo-plane-sf-p... I stand by the parent having some useful data and analysis, and the OP being totally speculation, and in many respects uninformed. - number 1, if you say 'loss of power', makes sense as a possible cause. if you say 'icing in the FOHE', it's like sa…

>no icing conditions

Icing in the fuel lines may be caused by fluid flowing through an orfice (pressure differential). All that is needed is water in the fuel.

Re: Armchair air crash investigator

#123

Post by damian2000 »

lisper wrote: post #45
jevinskie wrote: post #39

Earlier quoted context omitted.

Why is this? Can they do a better (in terms of passenger comfort) job landing manually?

No, autoland is pretty good. But there are two factors that cause pilots to land manually most of the time: 1) pilots think they are better at handling last-minute unexpected contingencies like wind sheer or bird strikes (and they may well be right about that) and 2) pilots don't want to give the Powers that Be any additional data to suggest that they aren't actually needed to fly a plane at all. The fact of the matt…

Getting in a Google self driving car is one thing, where you still have the ability to take over control or apply brakes yourself. But how many passengers would be willing to get on a fully self piloting aircraft? I think not too many, at least at first.

Re: Armchair air crash investigator

#124

Post by ricardobeat »

jrockway wrote: post #79
avree wrote: post #22

Earlier quoted context omitted.

Well, the whole blog design is very gray-area 'theft' of Medium's design.

I don't know what Medium is, but ... a white page with a title on the top? This is just as much a 'theft' of the default Apache "It works!" page.

Design is about choices. In this case you can point out:

    1. top-left square logo, dark gray, slab serif, fixed on scroll
    3. bold, large sans-serif title in "off-black"
    4. large serif body text with extended line-height
    5. 100% width image on top
Despite the visual simplicity, there are a lot of variables in effect. It's definitely "inspired" by Medium.

(medium has a few different post layouts, but they share the same spirit: https://medium.com/lift-and-drag/5f803f1482e3 vs https://medium.com/lift-and-drag/51691e99279f)

Re: Armchair air crash investigator

#127

Post by sneak »

snom380 wrote: post #97
CamperBob2 wrote: post #87

Earlier quoted context omitted.

Devil's-advocate: fine, OK, we still need pilots, for the time being. But do they actually need to be on the planes? In the case of two recent crashes (AF447 and this one, assuming pilot error turns out to be the cause as seems likely), it's safe to say that a computer would've easily done a better job than the pilots. Would be interesting to hear Capt. Sullenberger's take on the question.

Assuming we could make such a system secure and unhackable as well as unjammable, why would we want to? To save some money? I would rather pay a little more to have the pilot sit in the same airplane and have his life on the line as well. I just find it fascinating how obsessed people seem with getting rid of pilots. You don't often hear the same discussion about train or bus drivers, or doctors for that matter, even…

> I would rather pay a little more to have the pilot sit in the same airplane and have his life on the line as well.

I think I agree with you in general about this, but that's sort of a shitty and unpersuasive way of making that argument.

Re: Armchair air crash investigator

#128

Post by timcederman »

WalterBright wrote: post #35
bdirgo wrote: post #2

I heard a reporter on TV reporting that the airplane was doing cartwheels on the runway, and I pictured the semi-truck being flipped over in Batman. And then I thought what the hell could have done that? Fishtailed makes more sense, thanks for the clarification.

With cameras everywhere on the streets, I am baffled that there aren't cameras on the runways. Many, many airplane accidents on runways would be a lot easier to investigate, including, for example, the one where the SST caught fire.

There are runway cameras.

Re: Armchair air crash investigator

#129

Post by vl »

cpncrunch wrote: post #49
nostromo wrote: post #47

Curious as to why autopilot isn't being used to land planes yet. My understanding is that pilots can choose to use it to land, but only do so when visibility is very low. (ex: http://www.youtube.com/watch?v=DOFs-oa-bbc )

The autopilot requires the ILS to land the plane. If the ILS is inoperative, it can't autoland. However pilots do still land planes to keep their skills honed.

Presumably GPS and/or visual recognition system can be used to achieve the same, after all airstrip location is know in advance.

Re: Armchair air crash investigator

#130

Post by phire »

mikeash wrote: post #46
kop316 wrote: post #13

"The final bit of information is interesting. It shows a positive rate of climb – 120 feet per minute to be exact, which for a jet airliner, is very slow. For reference, at takeoff the vertical speed is most often +1500 feet per minute. Another interesting bit of information is the aircraft’s airspeed; 85 kts – for a Boeing 777 that is (and I’m guessing here) probably way below stall speed." That is actually expected…

It's been said, but I want to add weight to it: this is not at all expected. You never climb during a normal landing. I'd wager that 120fpm climb reading to be due to a measurement error of some kind, not actually something that really happened.

Looking at the GPS coordinates, the second to last reading was ~200m before the seawall, while the last reading was around halfway down the runway.

The plane is far outside it's normal operating conditions by this point, it's possible the plane instruments actually experienced a brief moment of 'climb' while the plane was crashing, or it could be equipment malfunction.

However, from what I can tell, the plane never reached that far down the runway. And the gps coordinates have actually snapped to the middle of runway 19L, near where it intercepts 28L, suggesting that flight radar 24 are doing some post-processing to make the planes stick to runways better.

I wouldn't trust that last data-point at all, as it's definitely post-seawall.

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