Definition of Service Ceiling...

[wo...@home.com]

I see very commonly that service ceiling is defined as the density
altitude where the climb rate reaches 100 fpm (in a single). I've
also seen where the single engine service ceiling in a twin is the
same but when the climb rate gets down to 50 fpm. Now, I'm almost
positive that I saw somewhere very recently that the service ceiling
for a twin is the same but 200 fpm.

Can someone please cite for me something that either supports or
disputes that definition for the twin engine plane?

Brad Wood
PA34-200T
AA5B

[Bob Lewis]

I found these two definitions in the official Flight Training Handbook
(AC61-21a).

For a twin:

The single engine service ceiling is the maximum density altitude at which
the single engine best rate of climb speed will produce 50 FPM rate of
climb. This ceiling is determined by the manufacturer on the basis of the
airplane's maximum gross weight, flaps and landing gear retracted, the
critical engine inoperative, and the propeller feathered.

For any airplane:

The service ceiling is the altitude at which the airplane is unable to climb
at a rate greater than 100 feet per minute.

I haven't heard/read anything about the 200 fpm reference.

Bob Lewis

wo...@home.com wrote in message <36a9296f.304069492@news>...