In article ,
(Jay) writes:


I'm not sure its fair to compare a 10" 1/4 HP electric fan to a 150HP
propeller.



Depends on how much of the output from each actually has contact with the
cooling surface. That 10" 1/4 hp fan is placed directly next to the radiator
and the output is forced through and past the cooling surfaces at a constant
and predictable velocity. The vast majority of the output from that 150 hp
propeller will not even be close to the cooling surface and its velocity will
varry considerably.

Bob Reed
www.kisbuild.r-a-reed-assoc.com (KIS Builders Site)
KIS Cruiser in progress...Slow but steady progress....

"Ladies and Gentlemen, take my advice,
pull down your pants and Slide on the Ice!"
(M.A.S.H. Sidney Freedman)