Unit 1
What two materials are aircraft cables made of?
High Carbon Steel and Corrosion Resistant Steel
Why is it important that control surfaces be balanced following repairs?
Eliminate or reduce the tendency of flutter.
Feathering, Flapping, Lead-lag
Autorotation
The rotation of rotorcraft blades solely by aerodynamic forces. (not powered or driven by the engine.
What is the purpose of the free wheeling unit (sprag clutch) in a helicopter drive system?
It disconnects the rotor whenever the engine stops or slows below the equivalent of rotor RPM.
What is the primary purpose of turnbuckles in aircraft systems?
Adjust tension of the cables.
The angle between the chord of the wing and relative wind in flight is known as?
Angle of Attack
A helicopter in forward flight, cruise configuration, will turn by? and is controlled by?
Tilting the rotor disk in the desired direction of flight. The cyclic
Wire Blending
Where would you find precise information to perform an alignment check for a particular aircraft?
Aircraft service or maintenance manual.
What are the two most common end connection found on aircraft cables?
Nico-press and Swage-type.
For an aircraft maintain a straight and level flight what must be true regarding the forces of flight?
They must be equal.
What device senses and automatically changes the power output of the engine when the collective is changed?
Governor
Dihedral
The positive angle formed by the lateral axis of the airplane and a line that passes through the center of the wing or horizontal stabilizer. Increases the lateral stability of the plane. Measured on the front spar.
What are three reasons an aircraft cable may be rejected from service?
Worn, distorted, corroded, or otherwise damaged cables”, Any cable that has one broken wire strand located in a critical fatigue area, Kinked cables or cables with a popped core or loose strands, Nylon-Jacketed cable with cracks or necking down in the Jacket, Wires “Blending” together, indicating wear of 40%- 50% through diameter of wires, Corrosion on the interior strands of the cable,Blending of the wires
What special part must be used on internally wrenched bolts?
A chamfered washer, to protect the radius of the bolt
If the elevator trim control tab is put in the nose down position what direction is the trailing edge of the trim tab? What direction should the elevator move?
Up, pushing the elevator down
Vertical vibration of a helicopter is primarily caused by
The main rotor being out of track
Angle of Incidence
Fixed angle between the chord line and the longitudinal axis of the aircraft
A pilot reports an airplane flies in a left wing heavy condition how may this be corrected?
Increasing the angle of incidence of the left wing, or decreasing the angle of incidence of the right wing, or both
Fairleads should never deflect the alignment of a cable than?
3 Degrees
An aircraft that has the tendency to gradually increase in a pitching moment is considered to have what?
Poor longitudinal stability
Dysentery of lift in a helicopter in forward flight is caused primarily by?
The difference in speed of the relative wind between the advancing and retreating rotor blades.
Translating Tendency
Is a single main rotor helicopter that tends to drift or move in the direction of tail rotor thrust.
The Three main drill indexes?
Fraction, Numbered, Lettered