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

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

#181

Post by inferiorhuman »

dang wrote: post #115
inferiorhuman wrote: post #98

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,…

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

As opposed to posting alternative facts and shallow dismissals? HN brings out a lot of knowledgeable folks, but on these 737 related posts the difference between HN and aviation centered forums is pretty stark.

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

#182

Post by burfog »

ruytlm wrote: post #20
koolba wrote: post #8

Earlier quoted context omitted.

Riding dead head as a pilot is normal. They do it all the time to get back home or wherever their next flight is from. Being in the right place, and happening to know exactly how to deal with what would otherwise kill the pilot and all the passengers, is incredibly fortunate.

I suppose similar in terms of the right place a the right time would be the QF32 incident[0], where by chance there were two additional pilots in the cockpit; a check captain, and a supervising check captain who was training that check captain. [0]: https://en.wikipedia.org/wiki/Qantas_Flight_32

Possibly a better example, with a DC-10 instructor on the plane as a passenger being pressed into service:

https://en.wikipedia.org/wiki/United_Airlines_Flight_232

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

#183

Post by crooked-v »

jimktrains2 wrote: post #32
flashman wrote: post #23

So a single point of failure (malfunctioning sensor) can engage the horizontal stabilizer without notifying pilots, in a way that the control yoke can't override. What the hell did Boeing think was going to happen?

Do we have a confirmed source that it can't be override by pilot input? My understanding was that using the stick could overcome it with other control surfaces and that the controls for trim can be set/reset by the pilot. I think Boeing has handled the aftermath (and much of the lead up since the release of the plane) very, very poorly. I, as a layman to aviation, am not willing to bet that Boeing knew the true likel…

> Do we have a confirmed source that it can't be override by pilot input?

Pilot input works... then MCAS silently does it again with up to +2.5 degrees additional adjustment, until after enough times it's maxed out the full rotation of the tail flap. See: https://www.seattletimes.com/business/boeing-aerospace/faile...

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

#184

Post by joecool1029 »

euyyn wrote: post #139
inferiorhuman wrote: post #70

Earlier quoted context omitted.

MCAS is a convenience feature that counteracts the plane's tendency to pitch up more than you want when climbing. Nope, MCAS is required to meet the requirements set forth by the FAA. That's not a convenience thing. Various nannies may seem like convenience things in a well balanced car, but they become far more important in a powerful, poorly balanced car like a Porsche 911 or Dodge Viper — cars that have earned rep…

Whatever is a car nanny?

Traction and stability control in modern cars.

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

#185

Post by phire »

Someone1234 wrote: post #128
js2 wrote: post #125

Earlier quoted context omitted.

Can you explain how they are different? Both cause the stabilizer to tilt. Both cause the stabilizer wheels next to the pilot/co-pilot to turn. If the plane is pitching down, and you pull back the yoke and that still doesn't recover, don't you at some point check the stabilizer angle? If it's wrong, you use the stabilizer trim switch on the yoke under your thumb to correct it. Won't you see the stabilizer wheel turn…

Runaway stabilizer causes a more dramatic sudden movement than MCAS. MCAS's start, wait 5 seconds, re-start, motion is more gradual. For example you could look at the wheel and it has stopped, only to re-start after you look away (add noise cancelling Bose headphones and you may not hear it) Pilots are trained well for runaway stabilizer, MCAS was essentially the same thing, but it didn't FEEL like the same thing, so…

Basically, the pilots would get more and more confused as their plane went more and more out of trim.

Now things are starting to make sense.

Boeing claimed (and F.A.A agreed) that pilots didn't need training because they already had training for a memory procedure which would have solved the issue.

They both appear to have overlooked is the MCAS symptoms were sufficiently different to the runaway stabiliser scenarios pilots trained on, that pilots are having problems knowing which procedure to apply.

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

#186

Post by TomMarius »

tomnm wrote: post #157
arcticbull wrote: post #126

Earlier quoted context omitted.

It's a single data point / anecdote. These investigations are incredibly thorough, precise, and authoritative so it makes sense they'd seek to exclude that kind of information until they knew for sure.

> It's a single data point / anecdote. A single data point is still a data point.

An irrelevant one in this case. This report needs to find out the technical/training/... reason, not why the other pilot needed a ride. I'm sure they'd have included it if they wanted to recommend having three pilots on every flight.

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

#187

Post by yason »

tomnm wrote: post #157
arcticbull wrote: post #126

Earlier quoted context omitted.

It's a single data point / anecdote. These investigations are incredibly thorough, precise, and authoritative so it makes sense they'd seek to exclude that kind of information until they knew for sure.

> It's a single data point / anecdote. A single data point is still a data point.

And a very relevant one, in this case: trim runaway with pilots not understanding it's a runaway. The visiting pilot does recognise the situation and restores expected flight dynamics. What went wrong, why did not two pilots realise something that is traditionally a known case and well understood? Because it didn't look like a traditional case.

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

#188

Post by StavrosK »

averros wrote: post #174
zaphirplane wrote: post #106

Earlier quoted context omitted.

This is very important, as it shows the ratio of pilots aware of the mitigation is low, and/or the stress of fighting with the the computer makes you forget you training amendments Edited to add it’s a training amendment

Actual instrument-rated pilot here. What people (including pilots) do under stress is resort to simple actions drilled in by training. That's why emergency procedure training is a major part of pilot training curriculum. What goes away first under stress is capability for complex reasoning, which is what one would need to figure out what the heck is going on and take appropriate action. In this case an a/c doing unco…

My question is why doesn't the "omg something is seriously fucked up give me manual control NOW" button disable the MCAS as well? That seems like a UX failure.

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

#189

Post by inferiorhuman »

tyingq wrote: post #121
twblalock wrote: post #87

Earlier quoted context omitted.

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

Various pilot unions aren't mincing words. Here's one quote: "This is the first description you, as 737 pilots, have seen,” the message from the pilots association at American reads. “It is not in the American Airlines 737 Flight Manual … nor is there a description in the Boeing FCOM (Flight Crew Operations Manual). It will be soon.” It doesn't seem unreasonable to me that the jumpseat rider made an educated guess ba…

It doesn't seem unreasonable to me that the jumpseat rider made an educated guess based on some prior experience. Aided by the fact that he didn't have other things to do besides observing.

Or he went back into the cabin and pulled out a copy of the FCOM to do some emergency diagnostic work.

https://www.grid.id/read/04966850/deretan-kejanggalan-yang-d...

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

#190

Post by dpe82 »

StavrosK wrote: post #188
averros wrote: post #174

Earlier quoted context omitted.

Actual instrument-rated pilot here. What people (including pilots) do under stress is resort to simple actions drilled in by training. That's why emergency procedure training is a major part of pilot training curriculum. What goes away first under stress is capability for complex reasoning, which is what one would need to figure out what the heck is going on and take appropriate action. In this case an a/c doing unco…

My question is why doesn't the "omg something is seriously fucked up give me manual control NOW" button disable the MCAS as well? That seems like a UX failure.

That's an excellent question, and will likely be one of the conclusions of the accident investigations.
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