1) The effects of aerodynamic compressibility become most apparent at Report

Transonic speeds

Supersonic speeds

Hypersonic speeds

2) Large, high-speed aircraft are normally fitted with power-operated flight control systems because Report

The weight of cable-operated systems would be too great

Of their size and weight

The air loads acting on their control surfaces are very high

3) Under standard atmospheric conditions, the speed of sound at sea level is approximately Report

678.9 mph

663.9 mph

761.9 mph

4) Under standard atmospheric conditions, at 60,000 ft., where the temperature is approximately -69F, the speed of sound would be Report

761.9 mph

660.7 mph

735.4 mph

5) An aircraft's forward air speed that is below Mach 1 is considered to be Report

Subsonic

Transonic

Hypersonic

6) An aircraft's forward air speed that is between 1.2 M and 5.0 M is termed Report

Hypersonic

Transonic

Supersonic

7) What is one common disadvantage with the formation of both an oblique and normal shock wave? Report

Both speed-up the airstream

Both cause erratic, uncontrollable vibrations

Both are wasteful of energy

8) The aerodynamic term "area rule" means: Report

The area of cross-section should increase gradually to a maximum and then decrease gradually.

The planform of the wing should match the planform of the empennage tail plane surface.

The mean chord of the tail plane must be 1/2 the thickness of the mean chord of the wing.

9) An aircraft's forward air speed that is between 0.75 M and Mach 1.2 is considered to be Report

Subsonic

Transonic

Hypersonic

10) An aircraft's forward air speed that is above 5.0 M is considered to be Report

Hypersonic

Supersonic

Transonic

11) An important design technique used to minimise drag at transonic speeds is the Report

Use of titanium for control surfaces

Use of diffusers on engine inlets

Supersonic area rule

12) An undesirable feature of a sweptback wing design is Report

Reduced forward air speed

Increased tendency for a wingtip stall

Extreme tail plane down forces

13) Wingtip stalling of a sweptback wing can be prevented by using Report

Wing fences

Differential ailerons

Aileron upfloat

14) The helicopter equivalent of a rudder on a fixed wing aircraft is termed the Report

Antitorque rotor

Articulated rotor

Dynamic stability rotor

15) To counter the effects of gyroscopic precession, changes in blade pitch must be applied Report

At precisely the same position as the desired action

90� later than the input

90

16) The main purpose of a helicopter's tail rotor is to Report

Counter the effect of torque from the main rotor

Control the direction of travel

Improve dynamic stability

17) The lift characteristics of main rotor blades are optimised by Report

Blade twist

Blade flapping

Collective pitch

18) The lift characteristics of main rotor blades are optimised by Report

Blade twist

Blade flapping

Collective pitch

19) In a no-wind hover, the lift created by main rotor blades is Report

Greater from the retreating blades

Evenly distributed across the blades

Greater from the advancing blades

20) The initial sign of blade tip stall is Report

Vibration from the blades

The tail of the helicopter pitching up

The nose of the helicopter pitching up

EASA Questions Module 13 Set 8

Set 1

Set 2

Set 3

Set 4

Set 5

Set 6

Set 7

Set 8

Set 9

Set 10

Set 11

Set 12