Question

Consider a turbofan powered airplane with the following characteristics:

Available thrust: 16 256 N at sea level/per engine.

Weight: 88 251 N. Planform area: 29.24 m2 .

Number of engines: 2 Span: 16.25 m

Span efficiency factor: 0.81

Parasite drag coefficient: 0.02

Maximum lift coefficient: 2.0

Specific fuel consumption: 0.6/h

How far will this airplane glide if the engines stop at 10 000 m altitude?

Answer 1

Write the equation for the drag coefficient Cp-CDst rel Aspect ratio) Te_ Substitute the given values (2.0)2 G+(0.02)+ 16.25 29.24 =0.194 Under engine operating condition, thrust produced by the engine balances the drag force due to the air Substitute the given values

(0.194) (0.4135) (29.24)2x (16256) 2x(16256) (0.194)(0.4135) (29.24) 2x(16256) (0.194)(0.4135) (29.24) -166.498 m/s Calculate the acceleration (retardation) when engines stop at given altitude. 2x(16256) 88251 9.81) -3.614 m/s Calculate the gliding distance using kinematic equation

(0) (166.498) +2(-3.614)s (166.498)2 2(3.614) 3835.305 m 3835.3 m