ARMY AVIATION INFO

Question 1

What is the typical structure of a helicopter (body of the craft) called?

Answer 1

The Fuselage

Question 2

Why does a helicopter need a main rotor?

Answer 2

To generate thrust

Question 3

What is the purpose of a tail rotor?

Answer 3

To counteract torque

Question 4

Why does a single rotor helicopter need a tail rotor?

Answer 4

To balance out the effects of torque

Question 5

On U.S model crafts, in what direction do the rotor blades conventionally spin?

Answer 5

Counter-Clockwise

Question 6

The rotor blades usually spin counter-clockwise in which countries?

Answer 6

The U.S.A, U.K, and Germany

Question 7

True or False: In a single main rotor helicopter, some of the power is used to counteract torque, rather than being used solely for lift.

Answer 7

True

Question 8

True or False: In a tandem rotor helicopter, some of the power is used to counteract torque, rather than being used solely for lift.

Answer 8

False.

Question 9

How many main rotors does a tandem rotor helicopter have?

Answer 9

Two

Question 10

True of False: A tandem rotor helicopter has a secondary/tail rotor.

Answer 10

False

Question 11

What is an advantage of the tandem rotor helicopter, in terms of torque and energy usage?

Answer 11

Each blade rotates counter to the other, meaning that torque is automatically offset.

Question 12

Is the Chinook one of the fastest aircraft in existence? If so, how?

Answer 12

Yes. Because of its tandem rotors, all of the power from the Chinook’s engine can be used in lift.

Question 13

On a Coaxial Rotor Helicopter, in which direction do the blades spin?

Answer 13

The two blades spin in opposite directions

Question 14

How are the blades displayed on a Coaxial Rotor Helicopter?

Answer 14

One blade sits on top of the other, mounted to the same mast.

Question 15

What is one thing that is reduced by a coaxial rotor?

Answer 15

Payload

Question 16

What advantage does an aircraft have by reducing payload?

Answer 16

By reducing payload, you are allowed to carry greater cargo and have a higher passenger capacity.

Question 17

What are four aerodynamic forces?

Answer 17

• Thrust
• Drag
• Weight
• Lift

Question 18

How is thrust transferred into motion?

Answer 18

By the use of the aircrafts mast and rotors

Question 19

What part of the aircraft creates thrust?

Answer 19

The aircrafts engine.

Question 20

What is drag?

Answer 20

A disruption in the flow of air due to the objects shape and size.

Question 21

What other aerodynamic force does drag act against?

Answer 21

Thrust.

Question 22

Name four different types of drag.

Answer 22

• Profile Drag
• Induced Drag
• Parasite Drag
• Total Drag

Question 23

Define Profile drag

Answer 23

Frictional resistance of a helicopters blades passing through the air.

Question 24

What are two forms of profile drag?

Answer 24

Form Drag and Skin Drag

Question 25

Which form of drag is being applied when there is an increase in drag due to an increase of speed of the helicopter?

Answer 25

Form drag

Question 26

The roughness of a rotors blade surface can increase the drag on a aircraft. Which form of drag is this?

Answer 26

Skin drag

Question 27

Which form of drag is caused by the airflow circulation around the blades?

Answer 27

Induced Drag

Question 28

What is parasite drag? Name a few examples.

Answer 28

Any external components to the aircraft. For example, landing gear, doors, or cowlings.

Question 29

When this is at its lowest value, the maximum endurance, and best rate of climb is achieved. What is it?

Answer 29

Total drag.

Question 30

What is the downward force which acts through the center of gravity on the helicopter?

Answer 30

Weight

Question 31

Can a helicopter increase its weight mid-flight?

Answer 31

Yes.

Question 32

Given an aircraft is banking or experiencing severe gusts. What force is applied to the aircraft? What happens as a result?

Answer 32

G force is applied to the aircraft, resulting in an increase of the aircraft's weight.

Question 33

What is the upward force created by the spinning of the helicopters blades, allowing air to pass over them?

Answer 33

Lift

Question 34

What is the term for a helicopter blades direction, relative to the air?

Answer 34

Angle of Attack

Question 35

How can the pilot change his/her Angle of Attack?

Answer 35

By moving the cyclic and collective

Question 36

What are some non-user factors that could impact your Angle of Attack?

Answer 36

- Blade flapping - Blade flexing - turbulent conditions

Question 37

Is the Angle of Attack a mechanical or aerodynamic angle?

Answer 37

Aerodynamic

Question 38

Is the Angle of Incidence a mechanical or aerodynamic angle?

Answer 38

Mechanical

Question 39

What is the intersection of the chord line with the plane of rotation?

Answer 39

The Angle of Incidence OR The blade pitch angle