Aviation & Aeronautics
Intermediate

Thrust Horsepower

Thrust horsepower is the engine's brake horsepower multiplied by propeller efficiency — the power actually converted to thrust.

Formula

THP=BHP×ηpTHP = BHP \times \eta_p

Variables

THPThrust horsepower
BHPBrake horsepower
\eta_pPropeller efficiency

Example

200 BHP at 85% efficiency: THP = 170 hp

Did You Know?

Even a great propeller wastes some power — typical efficiency peaks around 85% at cruise.

powerpropellerperformance

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