An aircraft is cruising with lift coefficient of 2.5 and thrust loading of 0.6. Find drag coefficient of the aircraft.

A)
1.5
B)
2.5
C)
2.9
D)
3.4

Correct Answer :   1.5


Explanation : Given, lift coefficient CL = 2.5, thrust loading T/W = 0.6.
Now, thrust loading at cruise is given by,
T/W = CD / CL
0.6 = CD / 2.5
CD = 0.6*2.5 = 1.5.