The Allison T56 turboprop engine is rated at 4,910 equivalent shaft horsepower at zero velocity at sea level.
The Allison T56 turboprop engine is rated at 4,910 equivalent shaft horsepower at zero velocity at sea level. Consider an airplane with this engine flying at 500 ft/s at sea level. The jet thrust is 250 lb, and the propeller efficiency is 0.9. Calculate the equivalent shaft horsepower at this flight condition.
\[P_{eq,shaft} = P_{shaft} + P_{Thrust}\]\[P_{shaft} = 4910\]
\[P_{Thrust} = \frac{T_{j}V_{\infty}}{\eta _{p}} = \frac{250\left ( 500 \right )}{ 0.9} = 138888.89\]
\[\Rightarrow P_{eq,shaft} = 4910 + 138888.89 = 143798.89\]
