Problem 2 (flight determination of drag polar): Consider a 60,000 lb. aircraft, with a wing-area of 1000 ft. A series of tests were attempted at sea level (density: 0.002377 slug.ft) to achieve cruise flights. It was observed that with a propulsion system generating a maximum of 4000 lb. thrust, the cruise flight could be maintained only at a velocity of 300 ft.sec. Determine the drag-polar of the aircraft, i.e., determine the parameters CD, and K. Based on observations Dmin = 4000 16 Corresponding to V = 300 ft/sec. In this flight D Tavail Dmin e 300 CD max 8 = 200 2 = Coo W & 4 = evs evs 4000 00187 4000 = Domin = 1/2 Ps (260) Goo = p(300/2/1000) 2W = C ev's Go G = D min K = Fet Goo/ =>K = 0.0594