10 Design calculations for a new single-engined light aircraft assume that it is flying at an altitude where thelair density is 1.0 kg.m$^{-3}$. Its current mass is 2,000 kg, its wing area is 20 m$^2$ and its drag polar is: $C_D = 0.04 + 0.08C_L^2$ Find: (a) the maximum rate of climb of the aircraft if its engine can develop a thrust of 5 kN; [7 marks] (b) the maximum angle of climb with the same engine, and the rate of climb at that angle; [8 marks] (c) the minimum rate of descent of the aircraft if the engine fails. [7 marks] (d) State any assumptions implicit in your calculations. [3 marks]