Blackbox - 02 - Deadly Weather - Part 5 of 5

[ogormanator]

Who narrates this series?

[hairyfatslobpig]

Wrong about the rudder servo valve, it was hot oil injected into a cold servo that would cause opposite direction. Not particles!

[unoriginalsyn]

@hairyfatslobpig well the experts and evidence suggests otherwise!

[KJLesnick]

@hairyfatslobpig

Yeah, thermal shock...

[dks11000]

a 737 take every 12second in the world(2010 update)

[Mrcynister]

Now if this was something that was done intentionally by somebody.......do you really think that the government would admit it, due to the panic it could produce.......hmmmmmm.

[TezzAtari]

well, the rudder jamming and/or operating in reverse on the 737's at that time was due to the unknown design flaw with the servo valve which ocurred when under the normal in flight conditions of -40 degrees whilst having the heated hydrolic fluid running through it.

After the very long investigation, they have all been replaced in recent years at great cost to Boing. There should be no need for an increased landing speed but maybe this is the case to further aid prevention?

[kieran08910715]

Black box was definitely one of the better Air Accident programs, and that episode was probably the most interesting.

[Shardith]

I wonder why they put the 737 rudder incidents under the "deadly weather" category, since it was finally discovered to be the fault of the faulty servo valve.

[CraigJ63]

9:30 Delta and ValuJet? It's the prince and the pauper!

[Honeymouu]

goodbye value jet.

[faffaflunkie]

@Honeymouu "Value Jet" is now "Air Tran" (rated highly I might add).

[prnces858]

@Honeymouu hello air tran...lol

[falconlem]

The National Transportation Safety Board determines that the probable cause of the USAir flight 427 accident was a loss of control of the airplane resulting from the movement of the rudder surface to its blow down limit.The rudder surface most likely deflected in a direction opposite to that commanded by the pilots as a result of a jam of the main rudder power control unit servo valve secondary slide to the servo valve housing offset from its neutral position and over travel of the primary slide

[qwerty112311]

wikipedia

[falconlem]

This ended up being mechanical failure, watch the seconds from disaster episode. this was made 2 years after the disaster.  But it was solved eventually. READ IT MECHANIC!

[seichel07]

I've been an aircraft mechanic for six years now, strange that I've never heard of this before. Very unique design flaw.

[helsinkisuomi]

I think this was probably fixed before you became an aircraft mechanic. And I remember from other shows that the investigators really had to think outside of the box to find the cause. Unique it was.

[JRattlesnake]

Isn't this the reason that 737's are now required to land at a faster speed? The failure of this servo was found not to be likely to happen at a faster speed. I think there must be a likely chance of another problem arising from landing faster. I am surprised that there have been no comments thus far. Thanks for the video.