Question

Which of the following is correct for horsepower (hp) to the weight ratio?

(a) T/W = (550*η / V) * (hp/W)

(b) T/W = (550*η / V)

(c) T/W = (550*η / V) + (hp/W)

(d) T/W = (550*η / V) – (hp/W)

I have been asked this question by my school principal while I was bunking the class.

This question is from Thrust Weight Ratio-1 in section Thrust-Weight Ratio and Wing Loading of Aircraft Design

Answer 1

Right option is (a) T/W = (550*η / V) * (hp/W)

For explanation I would say: Power is defined as thrust into velocity. Propeller will be operating with some finite value of propeller efficiency ƞ. 550 we multiply as to make units similar both the side.

In general, for prop aircraft thrust loading and power loading is given as,

T/W = (550*η / V)*(hp/W)