chapter 1 helicopters Test 2

An out-of-balance rotor blade on a helicopter causes a _ vibration, or a/an __ movement. -

Lateral, Side-To-Side swinging

An out-of-track rotor blade on a helicopter causes a _ vibration or a/an movement. -

Vertical, Up-And-Down

Rotor tracking systems have focused on providing information that can be used to adjust the
_ and to make the blades fly perfectly. -

Pitch Links, Tip Tabs

A force that is placed on a body measured in force per unit area is called _. -

Stress

The two basic types of stress on a helicopter rotor system are and _. -

Tension, Compression

The three other forms of stress that are combinations of the two basic forms of stress in Question #5 are __, ___, ___. -

Bending, Shear, Torsion

The condition known as ____ happens when vibrations within the helicopter are amplified by contact with the ground and can lead to total destruction of the aircraft. -

Ground Resonance

The method of blade tracking optically without a strobe light is called _. -

Electric - Optical Tracking

[MC]
Each time the helicopter lifts off the ground, the transmission mount/mast tube is subjected to what type of stress?

Tension

[MC]
What type of stress is the same transmission mount/mast tube subjected to when it lands?

Compression

[MC]
Which of these causes crystallization of metal, which can lead to mechanical failure?

High-frequency vibration

[MC]
A helicopter with twin mast, (one main rotor on each mast) where the blades intermesh during rotation is referred to as a?

Synchropter

[MC]
A helicopter that uses two main rotors that are mounted on the same mast (one above the other) is referred to as a?

Coaxial Rotor System

[MC]
A twin rotor helicopter where the one rotor is installed on the forward end of the helicopter and the second is installed on the aft end (one in front of the other) is referred to as a?

Tandem Rotor System

[MC]
A rotor system that allows an aircraft to operate as a helicopter and then transition to an airplane is referred to as a?

Tilt Rotor System

[MC]
A helicopter rotor system that uses a main rotor and a tail rotor is referred to as a?

Single Rotor System

[MC]
Which force tends to pull a component apart?

Shear

[Essay]
On a fully articulated rotor system, what job do blade feathering, lead-lag, and flapping perform? -

These three features help compensate for dissymmotry of lift.

[Essay]
What techniques are used to compensate for a rotor blades uneven lift characteristics during flight? -

Dissymmetry of lift is corrected by blade flapping, cyclic control, and blade twist for even lift distribution.