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AVIA 305 QUIZ Aircraft Performance - Questions and Answers
Question 1: An airplane is towing a glider to altitude. The tow
rope is 20° below the horizontal and has a tension force of 300 lb exerted on it by the airplane. Find the horizontal drag of the glider and the amount of lift that the rope is providing to the glider. Sin 20° = 0.342; cos 20 °= 0.940.
CORRECT ANSWER : Drag: D = 282lbs CORRECT ANSWER : Lift: Lift = 102.6 lbs
Question 2: A jet airplane is climbing at a constant airspeed in
no‐wind conditions. The plane is directly over a point on the ground that is 4 statute miles from the takeoff point and the altimeter reads 15,840 ft. Find the tangent of the plane's climb angle and the distance that it has flown through the air.
CORRECT ANSWER : Tangent of the plane's climb angle: Tan
= 0.75
CORRECT ANSWER : Distance flown through the air: Da = 5sm
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Question 3: Find the distance (S) and the force (F) on the seesaw
fulcrum shown in the figure. Assume that the system is in equilibrium. For the system to be in equilibrium, the moments on the left and right of the fulcrum must be equal.
CORRECT ANSWER : Distance: S = 8 CORRECT ANSWER : Force: F = 30
Question 4: The airplane in Problem 2 starts from a brakes‐
locked position on the runway. The airplane takes off at an airspeed of 200 fps. Find the time for the aircraft to reach takeoff speed. (Use answer from problem 2 as acceleration rate)
CORRECT ANSWER : T = 16.67 Seconds
Question 5: Under no‐wind conditions, what takeoff roll is
required for the aircraft in Problem 6?
CORRECT ANSWER : S = 1,667.7 ft
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Question 6: Upon reaching a velocity of 100 fps, the pilot of the
airplane in Problem 6 decides to abort the takeoff and applies brakes and stops the airplane in 1000 ft. Find the airplane's deceleration.
CORRECT ANSWER : A = 5fps²
Question 7: A helicopter has a rotor diameter of 30 ft and it is
being operated in a hover at 286.5 rpm. Find the tip speed of the rotor.
CORRECT ANSWER: Vt = 450 fps
Question 8: An airplane weighs 16,000 lb and is flying at 5000
ft altitude and at an airspeed of 200 fps. Find (a) the potential energy, (b) the kinetic energy, and (c) the total energy.Assuming no extra drag on the airplane, if the pilot dove until the airspeed was 400 fps, what would the altitude be?
CORRECT ANSWER : (a) Potential Energy: PE = 80,000,000 ft-lb
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CORRECT ANSWER : (b) Kinetic Energy: KE = 10,000,000 ft- lbs CORRECT ANSWER : (c) Total Energy: TE = 90,000,000 ft-lbs CORRECT ANSWER : Altitude after dive: Height = 3,125ft
Question 9: An aircraft's turbojet engine produces 10,000 lb of
thrust at 162.5 knots true airspeed. What is the equivalent power that it is producing?
CORRECT ANSWER : HP = 5,000hp
Question 10: An aircraft weighs 24,000 lb and has 75% of its
weight on the main (braking) wheels. If the coefficient of friction is 0.7, find the braking force on the airplane.
CORRECT ANSWER : Fb = 12,600lbs
Question 11: An increase in static air pressure
CORRECT ANSWER : affects air density by increasing the
density.