Airframe - Assembly and Rigging

The auxiliary (tail) rotor of a helicopter permits the pilot to compensate for and/or accomplish which of the following?. Torque and directional control. NIL.

The vertical flight of a helicopter is controlled by. Collective pitch changes. NIL.

A reduction in anti-torque thrust will cause the. tail to pivot in the direction of torque rotation around the main rotor axis. NIL.

In fotorcraft external-loading, the ideal location of the cargo release is where the line of action passes. through the center of gravity at all times. NIL.

The acute angle formed by the chord line of a wing and the relative wind is known as the. angle of attack. NIL.

A helicopter in forward flight, cruise configuration, changes direction by. tilting the main rotor disk in the desired direction. NIL.

The purpose in checking main rotor blade tracking is to determine the. relative position of the blades during rotation. NIL.

In a hovering helicopter equipped with a tail rotor, directional control is mantained by. varying the pitch of the tail rotor blades. NIL.

If a single-rotor helicopter is in foward horizontal flight, the angle of attack of the advancing blade is. less than the retreating blade. NIL.

Main rotor blades that do not cone by the same amount during rotation are said to be out of. track. NIL.

One purpose of the freewheeling unit required between the engine and the helicopter transmission is to. automatically disengage the rotor from the engine in case of an engine failure. NIL.

Which statement is correct concerning torque effect on helicopters?. Torque direction is the opposite of rotor blade rotation. NIL.

What is the purpose of the free-wheeling unit in a helicopter drive system?. It disengages the engine from the main rotor when engine RPM is less than rotor RPM. NIL.

Movement about the longitudinal axis (roll) in a helicopter is effected by movement of the. cyclic pitch control. NIL.

Movement about the lateral axis (pitch) in a helicopter is effected by movement of the. cyclic pitch control. NIL.

Wing dihedral, a rigging consideration on most airplanes of conventional design, contributes most to stability of the airplane about its. longitudinal axis. NIL.

Other than the manufacturer maintenance manual what other document could be used to determine the primary flight control surface deflection for an imported aircraft that is reassembled after shipment?. Aircraft type certificate data sheet. NIL.

If a pilot reports that an airplane flies left wing heavy, this condition may be corrected by. increasing the angle of incidence of the left wing, or decreasing the angle of incidence of the right wing, or both. NIL.

If the vertical fin of a single-engine, propeller-driven airplane is rigged properly, it will generally be parallel to. the vertical axis but not the longitudinal axis. NIL.

An airplane which has good longitudinal stability should have a minimum tendency to. pitch. NIL.

As the angle of attack of an airfoil increases, the center of pressure will. move toward the leading edge. NIL.

The angle of incidence is that acute angle formed by. a line parallel to the wing chord and a line parallel to the longitudinal axis of the aircraft. NIL.

An airplane's center of lift is usually located aft of its center of gravity. so that the airplane will have a nose-heavy tendency. NIL.

An airplane is controlled directionally about its vertical axis by the. rudder. NIL.

The elevators of a conventional airplane are used to provide rotation about the. lateral axis. NIL.

Washing-in the left wing of a monoplane, for purposes of rigging corrections after flight test, will have what effect on the lift and drag of that wing?. Both drag and lift will increase due to increased angle of attack. NIL.

What type of flap system increases the wing area and changes the wing camber?. Fowler flaps. NIL.

If the right wing of a monoplane is improperly rigged to a greater angle of incidence than designated in the manufacturer's specifications, it will cause the. airplane to be off balance both laterally and directionally. NIL.

The chord of a wing is measured from. leading edge to trailing edge. NIL.

When the lift of an airfoil increases, the drag will. also increase. NIL.

What physical factors are involved in the aspect ratio of airplane wings?. Span and chord. NIL.

Improper rigging of the elevator trim tab system will affect the balance of the airplane about its. lateral axis. NIL.

An airplane that has a tendency to gradually increase a pitching moment that has been set into motion has. poor longitudinal stability. NIL.

The purpose of wing slats is to. reduce stalling speed. NIL.

The angle of incidence of an airplane at rest. does not change when in flight. NIL.

Buffeting is the intermittent application of forces to a part of an airplane. It is caused by. an unsteady flow from turbulence. NIL.

Movement of an airplane along its lateral axis (roll) is also movement. around or about the longitudinal axis controlled by the ailerons. NIL.

The primary purpose of stall strips is to. stall the inboard portion of the wings first. NIL.

Rigging and alignment checks should not be undertaken in the open. However, if this cannot be avoided, the aircraft should be positioned with the. nose into the wind. NIL.

The correct dihedral angle can be determined by. using a dihedral board and bubble level along the front spar of each wing. NIL.

The dihedral angle of a wing may be measured by placing a straightedge and level protractor on the. front spar. NIL.

Where would you find precise information to perform a symmetry alignment check for a particular aircraft?. Aircraft service or maintenance manual. NIL.

Where is the buttock line or buttline of an aircraft?. A width measurement left or right of, and parallel to, the vertical centerline. NIL.

Where is fuselage station No. 137 located?. 137 inches aft of the zero or fixed reference line. NIL.

Proper wing twist in a sheet metal constructed wing can usually be checked by utilizing a. bubble level and special fixtures described by the manufacturer. NIL.

The vast majority of aircraft control cables are terminated with swaged terminals, that must be. cheched with a go-no-go gauge before and after, to show compliance with the manufacturer´s requirements after the swaging operation. NIL.

What nondestructive checking method is normally used to ensure that the correct amount of swaging has taken place when installing swaged-type terminals on aircraft control cable?. Use a terminal gauge to check the diameter of the swaged portion of the terminal. NIL.

When inspecting a control cable turnbuckle for proper installation, determine that. the safety wire ends are wrapped a minimum of four turns around the terminal end shanks. NIL.

If all instructions issued by the swaging tool manufacturer are followed when swaging a cable terminal, the resultant swaged terminal strength should be. the full rated strength of the cable. NIL.

Which is an acceptable safety device for a castle nut when installed on secondary structures?. Cotter pin. NIL.

When installing a castle nut, start alignment with the cotter pin hole at the. minimum recommended torque plus friction drag torque. NIL.

When used in close proximity to magnetic compasses, cotter pins are made of what material?. Corrosion resisting steel. NIL.

When a fiber or nylon insert-type, self-locking nut can be threaded on a bolt or stud through the insert with only the fingers, it should be. rejected. NIL.

The purpose of the vertical fin is to provide. directional stability. NIL.

How are changes in direction of a control cable accomplished?. Pulleys. NIL.

What is the smallest size cable that may be used in aircraft primary control systems?. 1/8 inch. NIL.

After repairing or re-covering a rudder, the surface should be rebalanced. to manufacturer´s specifications. NIL.

Placing a piece of cloth around a stainless steel control cable and running it back and forth over the length of the cable is generally a satisfactory method of inspecting for. broken strands. NIL.

The cable-operated control system of an all-metal aircraft, not incorporating a temperature compensating device, has been rigged to the correct tension in a heated hangar. If the aircraft is operated in very cold weather, the cable tension will. decrease when the aircraft structure and cables become cold. NIL.

Very often, repairs to a control surface require static rebalancing of the control surface. Generally, flight control balance condition may be determined by. the behavior of the trailing edge when the surface is suspended from its hinge points. NIL.

Excessive wear on both of the sides of a control cable pulley groove is evidence of. pulley misalignment. NIL.

Fairleads should never deflect the alignment of a cable more than. 3°. NIL.

Where does the breakage of control cable wires occur most frequently?. Breakage usually occurs where cables pass over pulleys and through fairleads. NIL.

With which system is differential control associated?. Aileron. NIL.

Which statement concerning the 100-hour inspection of an airplane equipped with a push-pull tube-type control system is true?. The threaded rod ends should be checked for the amount of thread engagement by means of the inspection hole provided. NIL.

If control cables are adjusted properly and the control surfaces tend to vibrate, the probable cause is. worn attachment fittings. NIL.

Aircraft flight control trim systems must be designed and installed so that the. pilot can determine the relative position of the trim tab from the cockpit. NIL.

Stability about the axis which runs parallel to the line of flight is referred to as. lateral stability. NIL.

The purpose of spring tabs or servo tabs is to. assist the pilot in moving the control surfaces. NIL.