Control Flashcards
Pitch
Elevators (and variable incidence tailplane)
Roll
Ailerons and spoilers
Yaw
Rudder
True or false- aircraft moves around its CG, but CG position can change
True
Why do we need aerodynamic balance
To achieve acceptable stick forces at all speeds
7 types of balance
- Inset hinge
- Horn balance
- Internal Balance
- Balance tab - moves opposite balance control
- Anti-balance tab - moves same as flight control
- Servo/spring servo - moves opposite
- Trim tabs - moves opposite
Hinge moments - size of moments depends on
- Deflection angle
- IAS
CG position affects size of pitch and yaw moments
Two advantages of internal balance
1) decrease stick force using pressure difference
2) less drag
How does balance tab move (geared tab)
Mechanical linkage moves H the opposite way automatically - the control moves down so it goes up
What is the function of balance and dreams that combined together?
The trim tab offset the zero stick force to a new location, i.e. the trimmed position
How does servo tab works
The force acting on the tab moves the control surface
What is one disadvantage of servo tab
Might get stuck, controls would be reversed
What is spring tab
An advanced servo tab, decreases stick forces at higher speeds only
What is the purpose anti-balance tab and how does it move
Increases stick forces
Moves is same direction as control surface
Stabilizer trim purpose and advantages
Changes stabilizer incidence.
Resulting in less drag, equal range of movement, and less flutter.
Greater speed range, greater CG variation, trim changes from powerful high lift device, tuck-under.
