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Old 9th Feb 2012, 21:46
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barit1
 
Join Date: Feb 2005
Location: flyover country USA
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Turbine D:
The fan can be windmilling in the opposite direction of normal rotation depending on wind direction. I am not sure, but, this could have a negative effect on starter life?
Negatory - The starter cranks the core rotor, which is (almost) never windmilling from terrestrial wind. And at very low rotor speed, there's negligible aero coupling between the core and fan. Most modern engines have minimal restrictions against starting in a tailwind.

(Although - recalling the first PAA 747 revenue flight, Jan. 1970, an engine stalled/overtemped when started in a tailwind. We've learned a lot since.)
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