Control Flashcards
Pulling the control column aft moves the elevator ____ ?
UP
Primary effect of elevator
PITCH
Secondary effect of elevator
AIRSPEED
How does faster airflow effect elevator responsiveness
Better elevator responsiveness
Smaller movements required
With a Forward CoG, what effect does this have on the elevator sensitivity?
LESS sensitive
Requires more pilot input to achieve same effect
In relation to the elevator, what is a danger on landing with a forward CoG
Not enough elevator authority
Not enough elevator to roll out or maintain nose up
What effect does Reward CoG have on elevator
MORE sensitive
Requires less pilot input to achieve same effect
In relation to the elevator, what is a danger on take-off with a rearward CoG
Overly sensitive elevator
Over rotation / Tail strike
In a roll to the right, what position are the ailerons on the left and right wings
Left wing = Up Going wing = Aileron DOWN
Right wing = Down Going wing = Aileron UP
Aileron down makes more camber, producing more lift, resulting in the outer wing in a roll creating more lift
Review here
What type of aileron is defined below
The up-going aileron goes up MORE than the down going aileron, trying to produce more drag
Differential Aileron
What type of aileron is defined below
Designed to penetrate into the airflow beneath the wing when the aileron is moved up
Frise Aileron
Small part of the aileron hangs below the wing when it is moved up into the airflow
What is the definition of adverse yaw
What causes it to happen
yaw moment towards the upgoing wing
Down going aileron produces more lift than upgoing aileron.
More lift creates more induced drag
What are 2 aileron designs to help counteract adverse yaw
- Differential Aileron
- Frise Aileron
Primary effect of rudder
YAW
Secondary effect of rudder
ROLL
Yaw causes one wing to travel faster than the other
Increased speed causes increase lift on the wing traveling faster
What does the following define
Small up and down movements felt on the control surface due to airflow
FLUTTER
What are 2 methods used for flying control balance
Mass Balance
Aerodynamic Balance
Where in relation to the hinge point is a mass balance (horn) situated
IN FRONT
Mass balance is situated infront of the hinge point
What are 2 benefits of a mass balance
Alleviate FLUTTER
Alleviate CONTROL HEAVINESS
help reduce flutter at high speed
aid pilot control manipulation at low speed
How does an aerodynamic balance work
20% of elevator surface protrudes into airflow below the hinge point
Airflow striking this part of the elevator counter acts the forces of airflow striking the bigger surface area
When the trailing edge of the tailplane moves UP, what tendancy does the nose have
NOSE UP
When the trailing edge of the tailplane moves DOWN what tendancy does the nose have
NOSE DOWN
What position is the anti-balance tab when the trailing edge of the tailplane is
1. UP
2. DOWN
Trailing edge UP = Anti Balance tab UP = Nose UP
Trailing edge DOWN = Anti Balance tab DOWN = Nose DOWN
Aircraft trimming systems apply to which controls, and what is their trim name called
Elevator - Pitch Trim
Rudder - Yaw Trim
Aileron - Roll Trim
What are 3 conventional types of trim
- Fixed
- Simple
- Spring loaded
Fixed Trim Tabs & Simple Trim Tabs
Which direction will the control surface deflect in relation to the trim tab itself
OPPOSITE DIRECTION
General Knowledge
When trimming nose DOWN, the trim tab moves UP into the airflow.
This pushes the elevator DOWN.
Remembering that the tailplane is an upside down wing, this has reduced the camber, reducing lift on the tailplane.
Remember that CoG is typically forward of CoL and has a typical nose down tendancy. This is normally counter acted by tailplane down force.
By reducing downforce on the tailplane, nose down tendancy takes precedence.
Hence, trimming nose DOWN makes the trim tab go UP and elevator go DOWN
When trimming nose UP, the trim tab moves DOWN into the airflow.
This pushes the elevator UP.
Remembering that the tailplane is an upside down wing, this has increased the camber, increasing lift on the tailplane.
Remember that CoG is typically forward of CoL and has a typical nose down tendancy. This is normally counter acted by tailplane down force.
By increasing downforce on the tailplane, nose down tendancy is counteracted.
Hence, trimming nose UP makes the trim tab go DOWN and elevator go UP
What are 2 issues of the stabilator Anti Balance Tab
- No pilot feedback to control loading
- “snatch” due to airflow changes
What is a stabilator
ALL FLYING TAILPLANE
All-moving tail surface
