Suppose a general aviation aircraft is in steady longitudinal flight in a vertical plane. The translational velocity vector of the aircraft with respect to a stationary atmosphere, expressed in a ground-fixed frame, has a constant ground speed of 160 ft/s and a constant rate of climb of 5 ft/s; the constant pitch attitude of the aircraft is given by 4 degrees. The aerodynamic drag polar of the aircraft is given by
The lift coefficient, expressed in terms of the angle of attack, is
where the angle of attack is measured in degrees.
a) What is the aircraft airspeed?
(b) What are the velocity components of the aircraft when expressed in the aircraftfixed frame?
(c) What is the aircraft angle of attack?
(d) What is the aircraft flight path angle?
(e) Draw a side view of the aircraft indicating the relevant aircraft-fixed and ground axes with origins at the aircraft center of mass; draw the velocity vector and indicate the pitch angle, the angle of attack, and the flight path angle. Verify that the pitch angle is the sum of the angle of attack and the flight path angle.
(f) What is the value of the lift coefficient at this flight condition?
(g) What is the value of the drag coefficient at this flight condition?
(h) What should be the elevator deflection at this flight condition so that the pitch moment is zero?