"His theoretical insights are grounded in an extended analysis of ship navigation—its computational basis, its historical roots, its social organization, and the details of its implementation in actual practice aboard large ships.":
USS McCain collision ultimately caused by UI confusion
221–230 of 369 posts
Re: USS McCain collision ultimately caused by UI confusion
#222Earlier quoted context omitted.
If you're going to go against the conclusions of the accident report, which is very thorough, you'll have to do more than just assert that the side sticks were responsible. Check it out here: https://www.bea.aero/docspa/2009/f-cp090601.en/pdf/f-cp09060...
First, I did not say the side-sticks are the fully responsible factor for the accident, but a contributing factor . Second (and as noted in the parallel subthread), the BEA report does not include cockpit transcripts in section 2, 2.1, and relevant subsections, in describing the cockpit situation. It mentions specific utterances of the crew, but not in the specific context and sequence they occurred. Other reports do…
I've addressed the popular mechanics article in other comments. It's difficult to square some of its key claims with the description of events in the accident report. In particular, the report gives no indication that any of the three pilots successfully identified that the plane was stalled.
The fundamental issue here is that if only one pilot has his hand on the stick (which should always be true) then linked sticks won't help much, and if both have their hands on the stick (which triggers both audio and visual warnings on the airbus) then they are already fighting over the sticks, indicating a total breakdown of cockpit discipline. The author of the popular mechanics article appears to think that it's normal for both pilots to be holding their sticks at the same time.
It's also worth noting that a half-competent PNF could have looked at (i) the pitch attitude, (ii) the throttle setting and (iii) the rate of descent and concluded that the plane was stalled. The fact that the PNF never managed to integrate these three very basic pieces of information makes it seem rather unlikely that he would have paid close attention to the position of his (hypothetically linked) control stick.
Note that when the PNF took over the controls briefly, he made a lateral input rather than pushing the stick forward! (p. 183)
Finally, sidesticks don't really have "a position". The airbus is usually flown using short movements away from center with the stick then returning to the center.
Re: USS McCain collision ultimately caused by UI confusion
#223Earlier quoted context omitted.
Figure 69 shows Bonin's stick inputs before Robert took control (and a few seconds after). As explained on p. 182 of the report, Robert pressed the override switch at this point and took control, so Bonin's stick inputs would have been ignored. Bonin then took back control by himself pressing the override switch. In effect, then, at this late stage, the pilots were fighting over the stick. If it had been a physical f…
There's a big difference between unknowingly fighting over the controls and knowingly fighting over the controls. If Robert had realized that Bonin was making the completely wrong control input then maybe he would have put a stop to it somehow. "Stop that, you'll get us all killed" is likely to be effective. He could have told the captain about it as soon as the captain arrived, rather than just before impact. Note t…
There's no indication that they were fighting unknowingly. I'm not sure what you're concluding that on the basis of.
>Note that when the incorrect input was finally identified by someone other than Bonin, it was corrected immediately, it was just far too late.
So the popular mechanics article says, but it's not so clear in the report that this ever really happened.
Re: USS McCain collision ultimately caused by UI confusion
#224Earlier quoted context omitted.
Figure 69 shows Bonin's stick inputs before Robert took control (and a few seconds after). As explained on p. 182 of the report, Robert pressed the override switch at this point and took control, so Bonin's stick inputs would have been ignored. Bonin then took back control by himself pressing the override switch. In effect, then, at this late stage, the pilots were fighting over the stick. If it had been a physical f…
With physically linked controls, direct physical feedback will tell you if the person in the other seat is fighting your inputs. Without them, that doesn't happen, so any explanation for the aircraft not responding to your inputs is potentially valid.
They most likely would have been aware of the audio and visual "dual input" warnings.
Re: USS McCain collision ultimately caused by UI confusion
#225Earlier quoted context omitted.
On a nuclear powered ship, yes, since you still essentially have a steam engine, the engine telegraph (throttle) isn't actually linked directly to the engine. On a modern diesel or gas turbine ship, no there's not. Obviously there are limits to what the engine can do still.
The nuclear part isn’t just used to generate electricity for the motors?
The nuclear power plant is heating water to generate steam.
Re: USS McCain collision ultimately caused by UI confusion
#226Earlier quoted context omitted.
User interfaces have gone backwards decades in quality. Look at your car radio in a 90's car. You didn't need to look at it to figure out how to push the radio button, turn the volume, anything. You could even adjust the bass on the fly with a bass knob instead of navigating to your "eq" menu to do it. Now, you've got to look away from the road, realize what "mode" your in, you can move the menu around to the "audio"…
That wasn't particularly early. I learned to drive in a used (but perfectly functioning, of course) '91 Lexus LS400. It was the make or break car for the new Lexus marque, and they put serious effort into the experience. It has excellent thermostat-controlled AC and heat, and it was very easily controllable using dedicated buttons without looking away from the road at all. I wish modern cars (cough, Tesla) would put…
Tesla's console is the embodiment of form over function for UI. It looks beautiful having a flowing button-free cockpit, but I'd rather be able to adjust settings without looking away from the road. Whatever happened to HUDs? It seems like a HUD with a dial on the steering wheel would let you have the best of both worlds.
Re: USS McCain collision ultimately caused by UI confusion
#227Earlier quoted context omitted.
Absolutely. Maintaining a ship's heading is a full time job. If you get distracted, you get off course pretty quickly. Speed isn't even really handled on the bridge. The engine order (ahead full, back half, emergency stop, etc) goes to the engine room where multiple people do the work. Note: This is in the context of oil and nuclear steam-powered ships. Gas turbine ships may well have an actual throttle on the bridge…
As an outsider (well, I have plenty of experience with pleasure boats/yachts, but none with large ships) it seems really extraordinary that just maintaining a heading would be a full time job. Somehow in airplanes a single pilot manages to control not only the rudder, but throttles, ailerons, elevators, flaps and whatnot while also yakking on the radio. And airplanes zip along at 500 knots rather than 20 like a ship.
Fewer obstacles maybe? Also, with a fast plane you either land or take off, or do stuff in practically free space.
Re: USS McCain collision ultimately caused by UI confusion
#228Earlier quoted context omitted.
This theory isn't citing the report itself, but independent analysis that's been done on the same data. The Wikipedia article on the topic has a whole section for these [1], and a section about this theory in particular [2]. Furthermore. The official accident report for crashes is not always considered the authoritative source for what happened. One good example is EgyptAir Flight 990 which the official report claims…
The theory is generally sourced from a popular mechanics article. There's nothing particularly authoritative about that "independent analysis". Goodness knows what you mean by the "same data". No third party has access to all the data recovered from the flight recorders and the wreckage. >conclusions that could result in the grounding of the entire worldwide Airbus fleet Concluding that the sidesticks were a contribu…
I think PM brought wide attention to it, but it's not like it's just some fringe theory of theirs, see e.g. this CBS report [1] from 2012 (after the PM article was published) with Captain Chesley Sullenberger (of the 2009 Hudson crash fame). Many aviation experts have weighed in on this.
Yes they don't have all the data, but they have enough to draw this sort of conclusion, including flight path, status of the plane at any given point, and the cockpit transcripts.
And true. Suggesting the fleet would be grounded was hyperbolic on my part. But I stand by my general point. Aside from happened in this accident, you're assuming that anything worthwhile to be learned from a given incident must be covered in the final report, or it must not be worth considering at all.
This expects too much of accident investigators, and doesn't account for the sort of institutional blindness that happens when everyone is used to things being done a certain way. Of course that was pilot error, two disconnected joysticks are just how planes are flown!
This wasn't the first case of an incident being attributed to Airbus's overdesigned flight controls, QF72 [2]. comes to mind.
1. https://www.youtube.com/watch?time_continue=62&v=kERSSRJant0
Re: USS McCain collision ultimately caused by UI confusion
#229Earlier quoted context omitted.
You seem awfully invested in quashing this particular line of argument. Mind my asking why?
I think it's wrong. If you think I am some kind of shill (?), then I guess it makes sense that you would be some kind of conspiracy theorist, given your unwarranted skepticism about the conclusions of the official report.
I made no such accusation.
There is considerable informed and expert opinion voiced that the conflicting inputs were a potential issue. A fair bit of that discussed here. There are other instances of conflicted inputs. And despite considering numerous elements of confusion, uncertainty, and information overload, the BEA report doesn't even consider the matter.
This calls into question the report itself, the investigation, and the investigators. Such processes are not perfect and may be subject to political pressures (say: EgyptAir Flight 990).
I've given the basis on which my skepticism is warrented. You've chosen not to accept it.
Cheers.
Re: USS McCain collision ultimately caused by UI confusion
#230Earlier quoted context omitted.
The theory is generally sourced from a popular mechanics article. There's nothing particularly authoritative about that "independent analysis". Goodness knows what you mean by the "same data". No third party has access to all the data recovered from the flight recorders and the wreckage. >conclusions that could result in the grounding of the entire worldwide Airbus fleet Concluding that the sidesticks were a contribu…
I think PM brought wide attention to it, but it's not like it's just some fringe theory of theirs, see e.g. this CBS report [1] from 2012 (after the PM article was published) with Captain Chesley Sullenberger (of the 2009 Hudson crash fame). Many aviation experts have weighed in on this. Yes they don't have all the data, but they have enough to draw this sort of conclusion, including flight path, status of the plane…
Every Airbus crash gives rise to lots of FUD in the media. Initially, everyone was blaming AF447 on the vertical stabilizer breaking off (http://www.businessinsider.com/henry-blodget-air-france-447-...). I guess they thought they had "enough" data then, and of course plenty of "experts" were on hand to lend credence to this particular speculation. But anyway, the accident report says what it says. I see no reason to put more trust in random newspaper/magazine articles that just riff on a standard template for covering Airbus accidents (it was the scary computers what dunnit).