Ch 18 - Control Flashcards
Principle of Operation
Local camber changing devices
Usually located on extremities
Aileron
Rate control - bigger movement of controls = faster rot
Does not change direction
Rudder
Displacement control - displaces aircraft from original flight path
Elevator
Displacement control - changes direction of aircraft
Hinge Moments
The more aerodynamic force generated from surface = the more you feel it in the controls
Aerodynamic Balance: The Inset Hinge
The hinge is inset up to 25% along the control surface so the force required to move it decreases
Aerodynamic Balance: Horn Balance
A section on the surface forward of the hinge line
Air gets caught under the front bit assisting in deflecting the surface
Aerodynamic Balance: The Internal Balance
A small diaphragm between the surface and main surface which is surrounded by q + p
Aileron still wants to get back to original position
Flexible diaphragm (rubber) resists motion basically
Aerodynamic Balance: Balance Tab
Makes controls lighter
Deflects in opposite direction to the surface (which balances it out)
These are inefficient (drag) and you lose a bit of control effectiveness
Aerodynamic Balance: The Anti Balance Tab
Makes controls heavier
Aerodynamic Balance: The Servo-Tab
Makes the controls much lighter
Moves the tab first and then the controls
Aerodynamic Balance: Spring Tab
Acts like a servo - tab at high speed (both move, tab first)
Acts like a balance tab at slow speed