Boeing Withheld Information on 737 Model, According to Safety Experts and Others

Re:Boeing Withheld Information on 737 Model, According to Sa... by foldr on Tuesday November 13, 2018 @08:09AM (#18440634)

> At full stabilizer travel you may not have sufficient elevator authority to overcome the downward pitch.

Do the stabilizer trim tabs really have more authority than the elevator? That seems odd.

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Re:Boeing Withheld Information on 737 Model, According to Sa... by voiture_rapide on Tuesday November 13, 2018 @08:30AM (#18440754)

They aren’t “trim tabs” — it moves the entire stabilizer.

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Re:Boeing Withheld Information on 737 Model, According to Sa... by FabHK on Tuesday November 13, 2018 @09:08AM (#18441001)

This article from 2013 outlines the differences quite nicely. It's a subtle point (that I hadn't appreciated before reading the article), but trim on a Cessna (on which many pilots learn) and modern jet work quite differently, though you rarely ever notice the difference in normal ops (because you never go massively out of trim). The author speculates that several accidents might be attributable to this.

Do you really understand how your trim works? Many do not, and why it matters. Alex Fisher - GAPAN

https://www.skybrary.aero/bookshelf/books/2627.pdf

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Re:Boeing Withheld Information on 737 Model, According to Sa... by VBprogrammer on Tuesday November 13, 2018 @10:25AM (#18441620)

I only really appreciated this while reading while reading about https://en.wikipedia.org/wiki/Alaska_Airlines_Flight_261

It's quite an interesting one if you are into that kind of thing.

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Re:Boeing Withheld Information on 737 Model, According to Sa... by inferiorhuman on Tuesday November 13, 2018 @12:50PM (#18442990)

Well an MD-80 does use trim tabs.

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Re:Boeing Withheld Information on 737 Model, According to Sa... by VBprogrammer on Tuesday November 13, 2018 @01:13PM (#18443226)

Not really. It trims via a moving stabiliser. You are confused because it has flying elevators and the pilot only directly controls the servo tabs which look a lot like trim tabs.

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Re:Boeing Withheld Information on 737 Model, According to Sa... by inferiorhuman on Tuesday November 13, 2018 @01:32PM (#18443415)

Ah yes, brain fart. Tabs for the elevator, jackscrew for the stabilizer.

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Re:Boeing Withheld Information on 737 Model, According to Sa... by foldr on Tuesday November 13, 2018 @08:36AM (#18440794)

Ah ok, that make sense.

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Re:Boeing Withheld Information on 737 Model, According to Sa... by Serow225 on Tuesday November 13, 2018 @10:56AM (#18441896)

Yes (but it's not tabs)

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