Assembly and Rigging Flashcards
The auxiliary (tail) rotor of a helicopter permits the pilot to compensate for and/or accomplish which of the following?
Torque and directional control.
The vertical flight of a helicopter is controlled by what?
Collective pitch changes.
A reduction in anti-torque thrust will cause the what?
tail to pivot in the direction of torque rotation around the main rotor axis.
In rotorcraft external-loading, the ideal location of the cargo release is where the line of action passes what?
through the center of gravity.
The acute angle formed by the chord line of a wing and the relative wind is known as the what?
angle of attack.
A helicopter in forward flight, cruise configuration, changes direction by what
tilting the main rotor disk in the desired direction.
The purpose in checking main rotor blade tracking is to determine the what?
relative position of the blades during rotation.
In a hovering helicopter equipped with a tail rotor, directional control is maintained by what?
varying the pitch of the tail rotor blades.
If a single-rotor helicopter is in forward horizontal flight, the angle of attack of the advancing blade is what?
less than the retreating blade.
Main rotor blades that do not cone by the same amount during rotation are said to be out of what?
track.
One purpose of the freewheeling unit required between the engine and the helicopter transmission is to what?
automatically disengage the rotor from the engine in case of an engine failure.
Which statement is correct concerning torque effect on helicopters?
Torque direction is the opposite of rotor blade rotation.
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.
Movement about the longitudinal axis (roll) in a helicopter is effected by movement of the what?
cyclic pitch control
Movement about the lateral axis (pitch) in a helicopter is effected by movement of the what?
cyclic pitch control
Wing dihedral, a rigging consideration on most airplanes of conventional design, contributes most to stability of the airplane about its what?
longitudinal axis
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.
If a pilot reports that an airplane flies left wing heavy, this condition may be corrected by what?
increasing the angle of incidence of the left wing, or decreasing the angle of incidence of the right wing, or both.
If the vertical fin of a single-engine, propeller driven airplane is rigged properly, it will generally by parallel to what?
The vertical axis but not the longitudinal axis.
An airplane which has good longitudinal stability should have a minimum tendency to what?
pitch
As the angle of attack of an airfoil increases, the center of pressure will what?
move toward the leading edge.
The angle of incidence is that acute angle formed by what?
a line parallel to the wing chord and a line parallel to the longitudinal axis of the aircraft.
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.
An airplane is controlled directionally about its vertical axis by the what?
rudder
The elevators of a conventional airplane are used to provide rotation about the what?
lateral axis
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.
What type of flap system increases the wing area and changes the wing camber?
Fowler flaps
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 what?
airplane to be off balance both laterally and directionally.
The chord of a wing is measured from…
leading edge to trailing edge.
When the lift of an airfoil increases, the drag will what?
also increase.
What physical factors are involved in the aspect ratio of airplane wings?
Span and chord.
Improper rigging of the elevator trim tab system will affect the balance of the airplane about its what?
lateral axis.
An airplane that has a tendency to gradually increase a pitching moment that has been set into motion has what?
poor longitudinal stability
The purpose of wing slats is to what?
reduce stalling speed.
The angle of incidence of an airplane at rest…
does not change when in flight.
Buffeting is the intermittent application of forces to a part of an airplane. It is caused by what?
An unsteady flow from turbulence.
Movement of an airplane along its lateral axis (roll) is also movement…
around or about the longitudinal axis controlled by the ailerons.
The primary purpose of stall strips is to what?
stall the inboard portion of the wing first.
Rigging and alignment checks should not be undertaken in the open. However, if this cannot be avoided, the aircraft should be positioned with the what?
nose into the wind.
The correct dihedral angel can be determined by what?
using a dihedral board and bubble level along the front spar of each wing.
The dihedral angle of a wing may be measured by placing a straightedge and level protractor on the what?
front spar.
Where would you find precise information to perform a symmetry alignment check for a particular aircraft?
Aircraft service or maintenance manual.
Where is the buttock line or buttline of an aircraft?
A width measurement left or right of, and parallel to, the vertical centerline.
Where is fuselage station No. 137 located?
137 inches aft of the zero or fixed reference line.
Proper wing twist in a sheet metal constructed wing can usually be checked by utilizing a what?
bubble level, and special fixtures described by the manufacturer.
The vast majority of aircraft control cables are terminated with swaged terminals, that must be what?
checked with a go-no-go gauge before and after, to show compliance with the manufacturer’s requirements after the swaging operation.
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.
When inspecting a control cable turnbuckle for proper installation, determine that what?
the safety wire ends are wrapped a minimum of four turns around the terminal end shanks.
If all instructions issued by the swaging tool manufacturer are followed when swaging a cable terminal, the resultant swaged terminal strength should be what?
the full rated strength of the cable.
Which is an acceptable safety device for a castle nut when installed on secondary structures?
Cotter pin
When installing a castle nut, start alignment with the cotter pin hole at the what?
minimum recommended torque plus friction drag torque.
When used in close proximity to magnetic compasses, cotter pins are made of what material?
corrosion resistant steel.
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 what?
rejected.
The purpose of the vertical fin is to provide what?
directional stability.
How are changes in direction of a control cable accomplished?
Pulleys.
What is the smallest size cable that may be used in aircraft primary control systems?
1/8 inch.
After repairing or re-covering a rudder, the surface should be rebalanced…
to manufacturer’s specifications.
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 inspection for what?
broken strands.
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 what?
decrease when the aircraft structure and cables become cold.
Very often, repairs to a control surface require static rebalancing of the control surface. Generally, flight control balance condition may be determined by what?
The behavior of the trailing edge when the surface is suspended from its hinge points.
Excessive wear on both of the sides of a control cable pulley groove is evidence of what?
pulley misalignment.
Fairleads should never deflected the alignment of a cable more than…
3 degrees.
Where does the breakage of control cable wires occur most frequently?
breakage usually occurs where cables pass over pulleys and through fairleads.
With which system is differential control associated?
Aileron.
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.
If control cables are adjusted properly and the control surfaces tend to vibrate, the probable cause is what?
worn attachment fittings.
Aircraft flight control trim systems must be designed and installed so that the what?
pilot can determine the relative position of the trim tab from the cockpit.
Stability about the axis which runs parallel to the line of flight is referred to as what?
lateral stability.
The purpose of spring tabs or servo tabs is to what?
assist the pilot in moving the control surfaces.
If the control stick of an aircraft with properly rigged flight controls is moved rearward and to the left, the right aileron will move how?
down and the elevator will move up.
Movement of the cockpit control toward the nose down position during a ground operation check of the elevator tab system will cause the trailing edge of the trim tab to move in which direction?
Upward regardless of elevator position.
If the control stick of an aircraft with properly rigged flight controls is moved forward and to the right, the left aileron will move…
down and the elevator will move down.
If the travel of an airplane’s controls is correct but the cables are rigged exceptionally tight, what probable effect will this have when flying the airplane?
The airplane will be heavy on the controls.
During inspection of the flight control system of an airplane equipped with differential-type aileron control side-to-side movement of the control stick will cause what?
each aileron to have a greater up travel (from the streamlined position) than down travel.
A universal propeller protractor used to measure the degrees of aileron travel should be zeroed…
with the aileron in the NEUTRAL position.
The universal propeller protractor can be used to measure what?
degrees of flap travel.
(Refer to figure 8) Identify the cable that is used in primary control systems and in other places where operation over pulleys is frequently.
3
A tension regulator in the flight control cable system of a large all-metal aircraft is used primarily to what?
retain a set tension.
(Refer to figure 9.) When the outside air temperature is 80 degrees F, select the acceptable 3/16 cable tension range.
117 pounds minimum, 143 pounds maximum.
Differential control on an aileron system means that what?
The up travel is more than the down travel.
Why is it generally necessary to jack an aircraft indoors for weighing?
so that air currents do not destabilize the scales.
Which should be accomplished before jacking an aircraft?
Install critical stress panels or plates.
