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USS McCain collision ultimately caused by UI confusion

arstechnica.co.uk

31–40 of 369 posts

Re: USS McCain collision ultimately caused by UI confusion

#31
post #27
post #22

Earlier quoted context omitted.

Once Bonin told them he had been holding the stick back the entire time, they immediately began a proper recovery, it was just far too late. This might have happened much, much earlier if the other pilot at the controls had been able to feel this.

What is your source for this? It does not seem consistent with sections 2.1.3.4-5 of the report. In any case, the captain was not holding a stick when he returned to the cockpit, as both pilots were in their seats. So the captain could not have gotten any tactile feedback regardless of the stick design.

This transcript: http://www.popularmechanics.com/flight/a3115/what-really-hap...

I’m not talking about the captain, I’m talking about the other pilot at the controls, Robert. He also held the stick back for some time, but he appears to have done this in the mistaken belief that the correct recovery procedure had been tried and failed.

Re: USS McCain collision ultimately caused by UI confusion

#32
post #17

The real cause of the collision was poor seamanship and failure to follow the COLREGS on the part of the bridge crew of the destroyer. Most specifically they were seriously in violation of Rule 6: the Safe Speed Rule http://navruleshandbook.com/Rule6.html Every vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropr…

I’m sorry for bringing this up here, but why do I need to scroll sideways in Safari on iphone on Hacker News every time there is a quote written in an unproportional font? Just, why?

Re: USS McCain collision ultimately caused by UI confusion

#33
post #21

Aside from the lack of clarity about which station has control over what, which should be made really obvious, with additional warnings when someone sets a control input on an inactive station, this seems bizarre to me: While the Ship's Control Console has a wheel for manual steering, both steering and throttle can be controlled with trackballs, with the adjustments showing up on the screens for each station. I've ne…

None of those operate on the open ocean.

There's a wheel there for steering; from the article it sounds like the trackball is used with a menu system of some type, not directly to set the steering angle.

Re: USS McCain collision ultimately caused by UI confusion

#34
Even specialised UIs need to be intuitive. You should need to know the domain (navigation), but not the specifics of everything the UI can show.

The problem with this kind of thing is people are sent on a course, which gives everyone a false sense of control and understanding. Clearly the crew didn't understand it, leading to a panic and wasted time.

Re: USS McCain collision ultimately caused by UI confusion

#35
post #32
post #17

The real cause of the collision was poor seamanship and failure to follow the COLREGS on the part of the bridge crew of the destroyer. Most specifically they were seriously in violation of Rule 6: the Safe Speed Rule http://navruleshandbook.com/Rule6.html Every vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropr…

I’m sorry for bringing this up here, but why do I need to scroll sideways in Safari on iphone on Hacker News every time there is a quote written in an unproportional font? Just, why?

Because the markup for those blocks isn't intended for general-purpose quotations; it's blocks. You don't word-wrap code.

Re: USS McCain collision ultimately caused by UI confusion

#36
post #31
post #27

Earlier quoted context omitted.

What is your source for this? It does not seem consistent with sections 2.1.3.4-5 of the report. In any case, the captain was not holding a stick when he returned to the cockpit, as both pilots were in their seats. So the captain could not have gotten any tactile feedback regardless of the stick design.

This transcript: http://www.popularmechanics.com/flight/a3115/what-really-hap... I’m not talking about the captain, I’m talking about the other pilot at the controls, Robert. He also held the stick back for some time, but he appears to have done this in the mistaken belief that the correct recovery procedure had been tried and failed.

That is an article in popular mechanics that contains a few excerpts from the transcript selected in order to make a particular point. The accident report gives a detailed description of the behavior of both pilots before the copilot entered (2.1.2.3).

One possible misconception here is that the copilot would have had his hands on the stick. It isn't normal for both pilots to have their hands on the stick. Only the pilot flying does -- for obvious reasons. At the stage where the problem developed, the copilot's attention, as the report explains, was mostly concerned with trying to interpret the ECAM warnings, and later with calling the captain. The idea that the copilot would have closely observed his own (hypothetically linked) stick and detected the problem, despite being fundamentally confused about what was going on, and having many more things on his plate, is little more than wishful thinking. The possibility cannot be conclusively ruled out, but there is no evidence that this would have happened.

Re: USS McCain collision ultimately caused by UI confusion

#37

Earlier quoted context omitted.

Happens more often than we like. I know of a ferry that a local warf built that had two bridges, and a combined throttle and rudder in each. The thing is that when moving from one bridge to the other, the crew had to flip a switch to indicate what direction was forward. And quite often they forgot. End result was a long history of damaged because ferry would ram the pier when the crew was actually attempting to move…

That is super dumb and dangerous. They should just flip the inputs on one end. EDIT (since some people obviously don’t understand the problem): ... so that each set of controls is always correct for the respective side on which it is located. No switch is necessary.

No, they just have a big button by each wheel marked "MAKE THIS THE BOW".

Re: USS McCain collision ultimately caused by UI confusion

#38
post #32
post #17

The real cause of the collision was poor seamanship and failure to follow the COLREGS on the part of the bridge crew of the destroyer. Most specifically they were seriously in violation of Rule 6: the Safe Speed Rule http://navruleshandbook.com/Rule6.html Every vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropr…

I’m sorry for bringing this up here, but why do I need to scroll sideways in Safari on iphone on Hacker News every time there is a quote written in an unproportional font? Just, why?

Because he used block quote syntax. It's designed for code on HN's implementation, so it preserves newlines, instead making you scroll.

It's a poor choice for quoting non computer languages.

Re: USS McCain collision ultimately caused by UI confusion

#39
post #17

The real cause of the collision was poor seamanship and failure to follow the COLREGS on the part of the bridge crew of the destroyer. Most specifically they were seriously in violation of Rule 6: the Safe Speed Rule http://navruleshandbook.com/Rule6.html Every vessel shall at all times proceed at a safe speed so that she can take proper and effective action to avoid collision and be stopped within a distance appropr…

Leave it to HN to uncover the real cause.

Re: USS McCain collision ultimately caused by UI confusion

#40
post #3

Amazing that someone would design in multiple steering wheels, only one of which is active, and no big indicator to make it super-obvious which one it is. Also amazing that there's a mode where moving a control sometimes controls all engines, sometimes just one.

I can imagine the requirements doc that led to that, where some Pentagon wonk was thinking "What happens if the helmsman is shot? If there's engine damage? If the helmsman is shot and there's engine damage?" and wrote all of those cases in, and completely forgot about the case where the bridge crew gets super confused because they triggered an edge case in the software and have no idea how to regain control of the ship.
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