Q. Gross weight of an airplane is 7000 N, wing area is 16 m2, and the maximum lift coefficient is 2.0. Assuming density at the altitude as 1.23 kg/m3, the stall speed (in m/s) of the aircraft Ans: 18.80 to 18.90
Q. The boundary layer thickness at the location of a sensor on a flat plate in an incompressible, laminar flow of air is required to be restricted to 1 mm for an effective measurement. If the flow velocity is 20 m/s with 1 bar pressure, 300 K temperature, and 1.789×10˗5 kg/(m-s) viscosity, the maximum distance
Q. Consider a 200 half-angle wedge in a supersonic flow at Mach 3.0 at standard sea-level conditions. If the shock-wave angle on the wedge is 360, the Mach number of the tangential component of the flow post-shock is (accurate to two decimal places). Ans: 47.0 to 55.0
Q. Air at 50 kPa pressure and 400 K temperature flows in a duct at Mach 3.0. A part of the flow leaks through an opening on the duct wall into the ambient, where the pressure is 30 kPa. The maximum Mach number achieved in the discharge is Ans: 3.30 to 3.40
Q. A spacecraft forms a circular orbit at an altitude of 150 km above the surface of a spherical Earth. Assuming the gravitational parameter, µ = 3.986 × 1014 m3/s2 and radius of earth, RE = 6,400 km, the velocity required for the injection of the spacecraft, parallel to the local horizon, is Ans: 7.80
Q. A pitot probe on an aircraft in a steady, level flight records a pressure of 55,000 N/m2. The static pressure and density are 45,280 N/m2 and 0.6 kg/m3, respectively. The wing area and the lift coefficient are 16 m2 and 2, respectively. The wing loading (in N/m2) on this aircraft is (accurate to one
A pitot probe on an aircraft in a steady, level flight records a pressure of 55,000 N/m2 Read More »
Q. An aircraft with a gross weight of 2000 kg, has a speed of 130 m/s at sea level, where the conditions are: 1 atmosphere (pressure), 288 K (temperature), and 1.23 kg/m3 (density). The speed (in m/s) required by the aircraft at an altitude of 9000 m, where the conditions are: 0.31 atmosphere, 230 K,
Q. A statically-stable aircraft has a 𝐶𝐿𝛼= 5 (where the angle of attack, α, is measured in radians). The coefficient of moment of the aircraft about the center of gravity is given as 𝐶𝑀,𝑐.𝑔 = 0.05 − 4𝛼. The mean aerodynamic chord of the aircraft wing is 1 m. The location (positive towards the nose)
Q. An aircraft with mass of 400,000 kg cruises at 240 m/s at an altitude of 10 km. Its lift to drag ratio at cruise is 15. Assuming g as 9.81 m/s2, the power (in MW) needed for it to cruise is Ans: 62.00 to 63.50
Q. Consider a cubical tank of side 2 m with its top open. It is filled with water up to a height of 1 m. Assuming the density of water to be 1000 kg/m3, g as 9.81 m/s2 and the atmospheric pressure to be 100 kPa, the net hydrostatic force (in kN) on the side
