Equivalent Shaft Horsepower (ESHP) is a term used in flight mechanics to quantify the power output or power required of a propeller-driven aircraft engine. It represents the combination of the engine’s shaft horsepower (SHP) and the power required to drive the propeller. This concept is particularly relevant for aircraft with a propeller, as it considers the power losses and efficiency of the propeller system.
ESHP=SHP+(Tj *Vinfinite/0.8*1000)
SHP = Shaft Horsepower of the engine T = Thrust developed by the propeller (thrust available) V = True airspeed of the aircraft in feet per second