Question

The formula for velocity of maximum specific endurance is _______________

(a) \(\big[\frac{3+n}{1+n}\big]^{\frac{1}{4}}\)Vmd

(b) \(\big[\frac{2+n}{1+n}\big]^{\frac{1}{4}}\)Vmd

(c) \(\big[\frac{2+n}{2-n}\big]^{\frac{1}{4}}\)Vmd

(d) \(\big[\frac{2-n}{2+n}\big]^{\frac{1}{4}}\)Vmd

The question was asked in an international level competition.

My question is from Cruising Performance topic in section Cruising Performance of Aircraft Performance

Answer 1

Correct option is (d) \(\big[\frac{2-n}{2+n}\big]^{\frac{1}{4}}\)Vmd

Best explanation: The formula forvelocity of maximum specific endurance is \(\big[\frac{2-n}{2+n}\big]^{\frac{1}{4}}\)Vmd where ‘n’ is the exponent and Vmd is maximum velocity. The value of ‘n’ depends on the value of bypass ratio of the engine. This implies that as the value of ‘n’ increases the bypass ratio increases.