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In a message dated 2/20/0 9:46:07 PM, you wrote:

<<If the number of stress cycles is the dominant
factor in determining fatigue life, why do Top
Fuel Dragsters have a TBO in the neighborhood of
three minutes?>>

I don't claim to be an expert in this area.  I don't have a clue about the
answer to this interesting question.  My prior comments were directed to the
notion that long-term damage would be forstalled if engines are operated at
low power settings on takeoff.  If they were not well expressed, I apologize
to anyone I've offended.

My comments were directed at the notion that partial-power takeoffs were
gentler on the engine, and thus preferable.  My thoughts are that safety is
enhanced by getting the takeoff finished quicker and gaining safe altitude
fast, suggesting that maximum available power should be used for takeoff.  
The takeoff is a small portion of an average flight, and the
engine-life-prolonging benefits of reduced power operation probably ought to
be realized in cruise, not on takeoff.

Concerning full-power runups, I do mine at 1700 rpm, but once on the runway I
throttle up to 100%, verify the correct RPM is attained, and that the engine
gauges are in the green and not changing.  So maybe this three-second
full-power check attains the same goal as the full-power runup.  I agree,
it's good to be sure you can get 100% power before you start rolling...

Happy flying.

- Rob
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