Aileron flutter / reversal??

[Bail out]

Hey folks,

has any body flying the B737 classic experienced any aileron flutter / reversal while flying the line?

I experienced the control yoke moving fairly aggresively left...right...left...right for about 5 secs last night.

Autopilot engaged
Alt 4000
Spd 300 knots and decreasing, speed brake FLT detent
a/c in a right turn
approx 15 miles on the ILS

It vanished as quickly as it appeared...??

thanks B

[alf5071h]

Bail out, IMHO
1. If the ailerons had fluttered, you would not be here to report it.
2. Powered controls do not feed back force to the control column, they are irreversible.
3. With the autopilot engaged it is most likely that the autos moved the controls. If you do not like what the autos are doing – disconnect.

Most probably cause:- ILS interference from preceding traffic / autopilot mode minor instability when joining ILS.

[Notso Fantastic]

Agreed as to the cause, but the 737 has power-assist controls whereby as backup in the event of total hydraulics failure, it can (just) be flown with manual controls. This was most certainly funny things on the localiser. 300 kts on the localiser will not be handled well by an autopilot.

[The Greaser]

Ah 300knots at 15 miles! Must be Ryanair again.

[411A]

Controll surface flutter?
Probably not, as the type is rather well known.

Anyway, I thought this was an A320 problem...:{ :uhoh:

[BLE]

Flutter is oscillations increasing in amplitude until structural failure occurs, so no flutter.

Reversal is when the flight control surfaces move the stick instead of stick moving the flight controls. Will only happen in aircraft with unpowered flight control surfaces. In a Learjet you could experience reversal in the form of aileron buzz at Mach above Mmo, progressing to mild aileron snatch due to shock wave moving aft and outboard on the wing, impacting the ailerons. But not at 300 KIAS low level, and certainly not in a Boeing 737.

What you probably have experienced is the increased roll rate which Boeing mentions in the very early FCTM:
Deploying speedbrakes when initiating a turn can cause a more rapid roll rate, which the A/P then will try to compensate for, thus the oscillations. You are working George too hard, and he is trying to tell you something!

Or maybe its just the guy next to you getting shaky because of your energy managment:ok:

[Miserlou]

Wake turbulence, also a possibilty.