tekelberry
Posts: 1309
Joined: Tue May 13, 2003 6:37 am

777 Flaps

Wed Jun 25, 2003 2:01 pm

I recently took a trip on a 777 and noticed that one of the flaps closer to the plane..or what appeared to be a flap...wasn't actually secure and was wiggling up and down. Is this normal? It didn't seem to affect anything...
 
AJ
Posts: 2295
Joined: Wed Nov 03, 1999 3:54 pm

RE: 777 Flaps

Wed Jun 25, 2003 2:18 pm

I think you're referring to the high-speed aileron, situated between the inboard and outboard trailing edge flaps behind the engine pylon. It is the primary source of roll control at high speed (flaps up), with both the high-speed and low-speed (located towards the wing tip) used when the flaps are extended. Roll control spoilers are also used when high roll rates are required.
 
AJ
Posts: 2295
Joined: Wed Nov 03, 1999 3:54 pm

RE: 777 Flaps

Wed Jun 25, 2003 2:22 pm

You can see them clearly in this shot deflected down (a trait borrowed from the 767 to reduce the pitch attitude on approach). They are outboard of the double slotted inboard flap directly behind the engine pylons:

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Photo © Carlos Borda


On the ground when the hydraulics aren't pressurised both high-speed ailerons droop.
 
tekelberry
Posts: 1309
Joined: Tue May 13, 2003 6:37 am

RE: 777 Flaps

Wed Jun 25, 2003 2:34 pm

Yep, those are the "things" I was talking about. You learn something new everyday...
 
JBirdAV8r
Posts: 3454
Joined: Sun Jun 24, 2001 4:44 am

RE: 777 Flaps

Wed Jun 25, 2003 2:49 pm

These are getting into technical aeras I don't have very far-reaching knowledge about, but the "wiggling" you referred to that didn't seem to have much effect on the airplane...is this part of the AFCS? If so, its purpose is to maintain directional/longitudinal stability of the airplane.
I got my head checked--by a jumbo jet
 
Ejazz
Posts: 689
Joined: Wed May 22, 2002 10:26 am

RE: 777 Flaps

Wed Jun 25, 2003 3:49 pm

On the B777 its actually a "Flaperon"

The flaperons provide roll control as per an aileron but to increase lift they move down and aft in proportion to trailing edge flap extension.

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Etihad Girl, You're a great way to fly.