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Old 9th Jun 2011, 03:38
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Brian Abraham
 
Join Date: Aug 2003
Location: Sale, Australia
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You have your work cut out for you Jane coming up with all the figures you request.

The conversion from Thrust to Horsepower, and visa versa, is not a straight conversion of units, such as Kilometres per Hour to Miles per Hour, it depends upon the Thrust and the speed of the aircraft, as derived from the basic relationship where -

Power = Force X Velocity.

As a straight conversion to eliminate the constants of the various units used, the following formula applies -

Pa = Ta V / 325, where -

Pa = Propulsive Power available in Horse Power, Ta = Thrust available in Pounds, and V = Velocity in Knots (if working in MPH use 375 as the constant rather than 325).

Taking the RR Merlin engine as an example, at a given horsepower setting the thrust produced produced would be vastly different between a Spitfire fighter and a Lancaster bomber.
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