Operation of Systems Flashcards
What are the Primary and Secondary Flight Controls?
Primary - Ailerons, Elevators, Rudder
Secondary - Flaps, Spoilers, Trim Devices, Leading Edge Devices
What are the different kinds of Flaps?
Plain
Split
Slotted
Fowler
What are the various Leading Edge Device Types?
Fixed Slots
Movable Slats
Leading Edge Flaps
What are the different types of trim devices?
Trim Tabs
Balance Tabs
Anti-servo tabs
Servo tabs
Ground adjustable tabs
What is a stabilator and how does it work?
A stabilitor is like a horizontal stabilizer that pivots to act like one big elevator. To keep abrupt control movements of this big surface from subjecting the tail to huge loads, stabilators typically use anti-servo tabs as a trim device. The anti-servo tab moves in the same direction as the trailing edge of the stabilator to provide a counter force. Piper Warrior, Archer and Cherokee use this system.
What are the different types of ailerons?
Plain ailerons
Differential ailerons
Frise-type ailerons
Flaperons
Explain Frise-type ailerons.
When banking the aircraft, an adverse yawing moment is caused by the drag from the lowered aileron. A Frise-type aileron is designed to extend its leading edge slightly into the airstream when raised thus creating drag to balance that out. This helps to equalize the drag between the wings and counteract adverse yaw. A Frise-type aileron may also creates a slot ahead of the lowered aileron to energize the boundary layer air and make it more effective at higher AOA.
Explain differential ailerons.
When banking the aircraft, an adverse yawing moment is caused by the greater drag from the lowered aileron than the raised aileron. With differential ailerons the raised aileron deflects further than the lowered aileron so that it can develop a similar amount of drag. This helps to equalize the drag between the wings and counteract adverse yaw.
Explain Ailerons.
Ailerons control roll about the longitudinal axis. They are movable surfaces mounted on the trailing edges of the wings controlled from the cockput wheel or stick through things like cables, pulleys, bellcranks, and pushrods.
The aileron on the outside of the turn is lowered creating additional lift which acts to raise that wing. At the same time, the aileron on the inside of the turn is lowered, reducing lift which acts to lower that wing.
Explain Adverse Yaw.
When ailerons are used to roll the plane on its longitudinal axis, the aileron to the outside of the turn is deflected downward creating additional lift which raises that wing. Remember that anytime you generate more lift you also generate more induced drag. At the same time the outer aileron is deflected down, the inside aileron is deflected upward which reduces lift. The wing on the outside of the turn has more drag than the inside wing which creates a yawing moment opposite the direction of the turn.
What is a balance tab?
A balance tab is like a trim tab in that it is attached to the trailing edge of the primary control surface and it moves in the opposite direction of deflection. The difference is that it does this automatically through a control linkage as the primary control surface moves. This makes the controls require less forced to move the primary control surfaces. It also serves as an adjustable trim tab.
What is a trim tab?
A trim tab is a small adjustable surface that is attached to the trailing edge of a primary control surface. It is adjusted by the pilot to aerodynamically reduce control force on the primary control surface. It is deflected in the opposite direction of desired primary control surface deflection.
What is a servo tab?
A servo tab is a control that is adjusted from the cockpit to move the primary control surface to the desired position aerodynamically.
What are the types of elevator?
Elevator
Stabilator
Ruddervator
