Re: Compressor Stall at Takeoff?

Date:         09 Dec 97 03:54:23 
From:         John Vincent Lombardi <uniphone@pacbell.net>
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>A few minutes later, the captain got on the loudspeaker and said that we had
>experenced a compressor stall in one of the engines. He said that it was
>common when taking off into a strong crosswind.

The B727 #2 engine is apt to compressor stall in strong crosswinds owing
to the length of the inlet duct. This was especially true for the early
model -100's (vortex generators were later added to the duct to smooth
the flow). Generally, the crosswind stall can be avoided by advancing
power on the outboards first, accelerating to 80 knots or so
(straightening out the flow into #2), and then advancing #2 throttle
slowly. This procedure naturally requires a suitably long runway.

The early turbojets and turbofans (JT3D, JT8D, etc.) were very
susceptible to compressor stalls, but damage rarely resulted. It isn't at
all uncommon to get a stall during engine acceleration, reduce throttle
to clear and then continue the takeoff as the engine spun back up
normally.

I think you'll find that stalls on engines with variable stators are more
serious and do require shutdown/inspection. Even some of those allow
continued operation if the engine stalled during transient throttle
movement.

The Captain did the right thing. He got on the PA right away to let
everyone know things were OK.

John Lombardi
uniphone@pacbell.net