Assembly and Rigging Flashcards
What are three types of commonly used flight control systems?
They are the cable, the push-pull, and the torque tube systems. The cable system is the most widely used because deflections of the structure to which it is attached do not affect it’s operating.
What is used in large metal aircraft to keep control cable tension within acceptable limits?
Because there is a considerable difference in temperature expansion between the aluminum aircraft structure and the steel control cables, some large aircraft incorporate cable tension regulators in the control cable systems. These regulators are designed to maintain a given cable tension. The unit consists of a compression spring and a locking mechanism that allows the spring to make corrections in the system only when the cable system is in neutral.
What is a fairlead?
It is a cable guide used to guide cables in a straight line through or between structural members of the aircraft. Fairleads should never deflect the alignment of a cable more than 3 degrees from a straight line.
Where does breakage of control cables occur most frequently?
Breakage of wire strands occurs most frequently where cables pass over pulleys and through fairleads.
Which flight control surfaces are considered the primary group?
The elevators, the ailerons, and the rudder.
Which flight controls are considered the secondary group?
The trim tabs and the spring tabs.
Which flight controls are included in the auxiliary group?
This group consists of the wing flaps, speed brakes, spoilers, slats, leading edge flaps and slots.
. How do wing flaps affect landing speed and approach angle of an aircraft?
The use of flaps increase the camber of a wing and therefore the lift of the wing making it possible for the speed of the aircraft to be decreased without stalling. This permits a steeper gliding angle to be obtained for the landing approach.
What is a balance tab?
It is an auxiliary control with fixed linkage that is designed in such a way that when the control surface is moved the tab moves in the opposite direction. Aerodynamic forces acting on the tab assists in moving the control surface.
. What is a trim tab?
It is an auxiliary control attached to the trailing edge of a control surface that is positioned by movement of a cockpit control to balance the forces acting on the control surface.
What is the purpose of the collective pitch control in a helicopter?
It is used to change the lift (pitch) of the main rotor blades.
What unit on a helicopter is used to compensate for torque created by the main rotor?
The tail rotor.
What control operates the helicopter tail rotor?
The anti-torque pedals.
What are the three axes of an aircraft, and which control surfaces cause the aircraft to move about each axis?
The axis of an aircraft can be considered as an imaginary axle around which the aircraft turns like a wheel. The axis which extends through the fuselage from nose to tail is the longitudinal axis. The axis which extends crosswise, from wingtip to wingtip, is the lateral axis. The axis which passes through the center from top to bottom, is the vertical axis. Motion about the longitudinal axis is called roll and is controlled by the ailerons. Motion around the lateral axis is called pitch and is affected by the elevators. Finally, motion about the vertical axis is called yaw and is produced by the rudder of the aircraft.
When installing an aircraft bolt, what precaution would you “take regarding the position of the bolt?
Where possible, the bolt head should be positioned on top when a bolt is installed vertically, and the bolt head should be forward when it is installed horizontally. In these positions the bolt is less likely to slide out if the locking device comes off.
