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Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

bloomberg.com

111–120 of 269 posts

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#111

Earlier quoted context omitted.

> More to the point, this reflects positively on Lion Air because it means that the pilots in the forward facing seats properly took advice into account. This is good crew resource management. It's good the pilots took advice -- but they should not have needed that advice because they should have been trained to operate the system properly. The whole thing reflects very poorly overall: - The pilots were not trained p…

The pilots were not trained properly on the new system It's hard to train for something that doesn't exist according to Boeing The plane was allowed to fly again the next day despite the malfunction The plane was serviced between flights, and assuming that Lion Air actually did what they claimed, Lion Air maintenance followed the Boeing instructions by the book. The incident was not reported properly at the time The…

> It's hard to train for something that doesn't exist according to Boeing

From the article:

> The so-called dead-head pilot on the earlier flight from Bali to Jakarta told the crew to cut power to the motor driving the nose down, according to the people familiar, part of a checklist that all pilots are required to memorize.

Clearly only one of the pilots memorized the checklist, but they were all required to do so. Presumably the pilots who crashed the plane the next day didn't memorize it either.

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#112

Earlier quoted context omitted.

> The deadheading pilot recognized a problem with something controlling the stabilizer and went off script. It's not like he was pushing random buttons. He knew what the system was, he knew that it was likely to be the cause of the problem, and he knew how to disable it. He must have been informed about the system.

He knew what the system was How would he know something that was undisclosed? It's not conjecture here, no airlines and no pilots knew of the presence of MCAS before the Lion Air 610 crash.

The article says that all of the pilots were supposed to know what to do in this situation:

> The so-called dead-head pilot on the earlier flight from Bali to Jakarta told the crew to cut power to the motor driving the nose down, according to the people familiar, part of a checklist that all pilots are required to memorize.

This guy didn't go off script. It seems like he was the only one of the three who knew the script.

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#113
post #105

Earlier quoted context omitted.

Boeing did inform them. Boeing did not inform any of the airlines of MCAS until after the Lion Air crash. Otherwise how would the third pilot have known what to do when he saved the plane? The deadheading pilot recognized a problem with something controlling the stabilizer and went off script. Edit: I love the downvotes from folks who haven't actually read any of the complaints from pilots. Since reading is too hard,…

> and went off script From the article: "told the crew to cut power to the motor driving the nose down, according to the people familiar, part of a checklist that all pilots are required to memorize. " Emphasis mine.

Yeah, that's part of the checklist for runaway trim (which I've posted in a previous comment). That same checklist says to stop if the stabilizer stops moving after you counter with trim button input. MCAS stops after you counter with the trim buttons.

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#114
post #85

Earlier quoted context omitted.

The symptoms of MCAS are the same as runaway trim No, they're not.

So, how are they not?

It feels different from their runaway stabilizer training. MCAS has a delay between each motion, whereas a runaway stabilizer is much more aggressive.

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#115

Earlier quoted context omitted.

Boeing did inform them. Otherwise how would the third pilot have known what to do when he saved the plane?

Boeing did inform them. Boeing did not inform any of the airlines of MCAS until after the Lion Air crash. Otherwise how would the third pilot have known what to do when he saved the plane? The deadheading pilot recognized a problem with something controlling the stabilizer and went off script. Edit: I love the downvotes from folks who haven't actually read any of the complaints from pilots. Since reading is too hard,…

Please don't break the site guidelines regardless of how wrong other commenters or voters may be. That only makes this place worse.

https://news.ycombinator.com/newsguidelines.html

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#116
post #108

Earlier quoted context omitted.

It didn't need to be included in the preliminary report since it is contextual/background information. They did include in the report that on a previous flight the same sensor error occurred and the pilots resolved it by disabling auto-trim. The fact there was a third pilot there is definitely interesting, but they didn't make anyone less safe by not including it in the report. There's no bombshell here. Previous pro…

It suggests that no LionAir crews knew how to handle this.

US pilots say they didn't either. The training wasn't out there.

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#117

Earlier quoted context omitted.

The pilots were not trained properly on the new system It's hard to train for something that doesn't exist according to Boeing The plane was allowed to fly again the next day despite the malfunction The plane was serviced between flights, and assuming that Lion Air actually did what they claimed, Lion Air maintenance followed the Boeing instructions by the book. The incident was not reported properly at the time The…

> It's hard to train for something that doesn't exist according to Boeing From the article: > The so-called dead-head pilot on the earlier flight from Bali to Jakarta told the crew to cut power to the motor driving the nose down, according to the people familiar, part of a checklist that all pilots are required to memorize. Clearly only one of the pilots memorized the checklist, but they were all required to do so. P…

Clearly only one of the pilots memorized the checklist

I've already posted the checklist. If you've memorized the checklist you'd know that it says to stop if the trimming stops once you hit the push buttons on the yoke. MCAS stops trimming when you manually input opposite trim (and you can see this on the black box graphs from the preliminary report).

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#118

Earlier quoted context omitted.

>I'm fairly certain that the characteristic "If this component malfunctions loss of life is one potential outcome" is a solid case for the component actually being safety critical. The same thing can be said for literally tons of components on a plane. You can't have them all be redundant. At some point you have to pick and choose. A sensor for an obviously supplemental feature seems like a pretty obvious one to choo…

> You can't have them all be redundant. Why not?

The usual, cost. But I wonder how much the redundant sensor costs for airlines to ditch it.

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#119
post #108

Earlier quoted context omitted.

It suggests that no LionAir crews knew how to handle this.

US pilots say they didn't either. The training wasn't out there.

The runaway stabilizer trim procedure is how it was expected to be handled:

https://www.flightglobal.com/news/articles/faa-order-tells-h...

https://www.youtube.com/watch?v=3pPRuFHR1co

The specifics of MCAS weren't out there because Boeing expected the pre-existing procedure to have been sufficient. That procedure wasn't sufficient, or the Lion and Ethiopian Air pilots were somehow not aware of it, or they forgot their training in a stressful situation.

To be clear: the planes should not have put these pilots into the situation they were in, but unless the recovery procedure doesn't work, these planes should not have crashed.

[One thing I've been wondering: somehow the pilots were able to bring the nose back up... it was only (apparently) after multiple nose downs that they eventually failed to recover the plane. What was going on there? It's as if they understood how to correct the stabilizer trim, but weren't aware of the cut-off switches.]

Re: Pilot Who Hitched a Ride Saved Lion Air 737 on the Day Before Deadly Crash

#120

Earlier quoted context omitted.

>I'm fairly certain that the characteristic "If this component malfunctions loss of life is one potential outcome" is a solid case for the component actually being safety critical. The same thing can be said for literally tons of components on a plane. You can't have them all be redundant. At some point you have to pick and choose. A sensor for an obviously supplemental feature seems like a pretty obvious one to choo…

> You can't have them all be redundant. Why not?

Redundant wings? Fuselage? Just 2 obvious examples, back to my armchair.
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