737 NG speedbrake IAS limits?

[Empty Cruise]

Hi all,

Have read numerous references (Bulfer, MRG) to the 737 NG speedbrake limitation being 320 KIAS due tailplane vibration.

Now, the problem is that I cannot find it in our FCOM. Has this been cleared via an AD or is it my outfit that have jumped the gun on the issue being resolved?

A reference would be great - I'm sure this is one that Chris or Pat would be able to help out with ;)

Brgds
Empty

[BOAC]

Waiting for the experts but I believe there is some limitation without a tail mod in place.

[CaptainSandL]

The limitation was actually not to exceed 300kts with the speedbrakes extended, with a warning that speeds in excess of 320 could cause severe vibration and damage.

This limitation should have been cleared from all fleets by having the elevator tabs “stiffened” IAW SB 737-55A1080. It was recommended to be done within 2 years of Sep 2004. You can check this visually on a walkaround by counting the number of hinges on each elevator tab, the modified ones have 6 hinges, the unmodified had 4.

You should also check this before any airtest as the elevator power off limits are slightly different.

S&L