Question

What is range factor in cruise method 1?

(a) \(\left[\frac{V_{mdi}}{C} E_{max}\right]\)

(b) \(\left[\frac{V_{max}}{C} E_{max}\right]\)

(c) \(\Big\{\frac{2u^3}{u^4+1}\Big\}\)

(d) \(\Big\{\frac{2u^4}{u^4+1}\Big\}\)

I had been asked this question in unit test.

This interesting question is from Cruise Method 1 topic in chapter Cruising Performance of Aircraft Performance

Answer 1

Correct choice is (a) \(\left[\frac{V_{mdi}}{C} E_{max}\right]\)

To explain I would say: Range factor in cruise method 1 is given by \(\left[\frac{V_{mdi}}{C} E_{max}\right]\). The range equation in cruise method 1 is given by R1 = \(\left[\frac{V_{mdi}}{C} E_{max}\right]\Big\{\frac{2u^3}{u^4+1}\Big\}\) ln ω where V is true airspeed, C is specific fuel consumption, L is lift, D is drag, Emax is endurance and ω is fuel ratio.