Aerodynamics & Flight Controls Flashcards
What axis is pitch
Lateral - wing tip to wing tip
What axis is roll
Longitudinal - nose to tail
What axis is yaw
Vertical - through the centre of gravity
control surface for yaw
Rudder
Control surface for roll
Aileron
Control surface for pitch
Elevator
Where and what are roll spoilers / speed brakes added for
Larger commercial aircraft & Increase efficiency of the flying surface
What happens if the right aileron is deflected upward
Decreased lift on right aileron , increase lift on left aileron
Aircraft rolls right
Are high speed ailerons inboard or outboard
Inboard
What’s bigger inner or outboard ailerons
Outboard
What can be used to help execute accurate turns
Roll spoilers
Where are elevators located
Trailing edge of horizontal stabiliser
What creates a nose down motion
Elevators deflected down
What pilot action can cause the aircraft nose to pitch up
Control column pulled rearwards
What is a stabilator a combination of
Elevator and horizontal stabiliser
Where are stabilators found
Light general aviation aircraft
High speed military combat aircraft
What’s another name for a variable incidence stabiliser
Trimmable Horizontal stabiliser ( THS )
What is a trimable horizontal stabiliser used for
Pitch trimming due to its limited range of movement
How does a variable incidence stabiliser reduce drag
It reduces the requirement for elevator deflection
Primary role of canard
Provide pitch control
How does the aircraft deflect the rudder left and what happens
Deflected left by pilot pushing left rudder pedal & aircraft is defected left
Why do we need a rudder limiter
To stop excessive use of the rudder at high speeds as it can cause structural failure on vertical stabiliser
What aircraft does adverse yaw happen in and how can you reduce it
Light aircraft & reduced by frise ailerons or differential ailerons
What’s an elevon
Combination of aileron and elevator
What type of aircraft uses a elevon
Delta wing aircraft
What is a ruddervator
Combination of rudder and elevator
What type of aircraft uses a ruddervator
V - tailed aircraft
How is an aileron controlled in the cockpit
Yoke or side to side of control colomn
What happens if pilot moves stick to the right
Right aileron up and left down
What happens to the ailerons in a left turn
Left aileron up and right down
How do spoilers supplement aileron control
Reduces lift on wing
How do elevators move
Up and down same time
What does pushing the pilot stick foward do to the elevator
Nose down attitude
What does pulling the pilot stick rearward do to the elevator
Nose up attitude
What attitude does a deflected up elevator give
Nose up
What attitude does a deflected down aileron give
Nose down
What is a stabilitator a combination of
Elevator and horizontal stabaliser
What type of aircraft is a stabilitor most common on
High speed
What is a variable incidence stabiliser also known as and what is it used for
Trimmable horizontal stabiliser
Used for pitch trimming
Where is a canard
Horizontal surface ahead of wings at the front
How can we overcome adverse yaw
Aileron rudder interconnect system
How is Dutch roll compensated
Sensed and corrected by yaw dampening system
What is the purpose of high lift devices
Increase lift produced by wing
Does a slot create lift
No , re-energise boundary layer to delay flow separation or prevent stall
Where are slots located
Outboard leading edge
What is a slot
Fixed convergent duct or gap
Where are slats located
Leading edge
Where are flaps located
Trailing edge on wings
What does a flap do
Increase lift at low speed used during take off and landing
How does deploying the flaps help the pilot
Causes a nose down attitude which aids the pilots view
Plain flap lift increase
50-55%
Split lift increase
60-65%
Slotted flap lift increase
65-70%
Fowler flap lift increase
95%
What flap gives the lowest drag possible
Slotted fowler
Decide where is leading edge located
Mounted of front part of wing
What is a flapperon
Combination of flap and aileron
What happens if a flapperon deflects collectively
Acts as a flap
What happens if a flapperon deflects deferentially
Acts as a aileron
What does a mixer do
Combines separate inputs into a single set of control surfaces
What does a spoiler do
Dump lift produced and increase drag
What is a flight spoiler used as
In flight speed brake
What’s a ground spoiler used for
Maximise wheel brake efficiency
What’s the advantage of a roll spoiler
Aircraft can roll without a twisting force
What type of aircraft are air brakes used on
High performer military and commercial aircraft
When are air brakes used
High performer military and commercial aircraft
What areas are speed brakes positioned in
Areas where structure can withstand heavy air loads
How does speed brakes help with decent
Controls it without an increase in speed
How many directions is span wise flow
2 , right angle to leading and follows leading edge
What happens if the centre of pressure is forward of the centre of gravity
Nose up pitch movement
What’s the purpose of a wing fence
Reduce the effects of spanwise flow and reduce wing tip stall on swept wing aircraft
Where is a wing fence placed
Leading edge where it will limit boundary layer outflow
What’s a saw tooth leading edge and what does it reduce
Extension of leading edge or zig zag cut out
It reduces wing tip stall on swept wings
What is a vortex generator
Device to reenergise boundary layer
How are vortex generators placed
Vertically on a surface of a large wing and it opposing pairs so the vortex’s mix
What is a stall wedge/strip and what is it made of
Leading edge device that encourages root to stall first
Made of alluminaum with triangular cross section
What is trimming
Adjusting aerodynamic forces on control surfaces so aircraft remains at set attitude with no control input
When can fixed trim tab be adjusted
Only on ground
What tab is not deflected in the opposite direction to the control surface
Anti balance
Disadvantage of balance tab
Reduces efficient of control surface
Disadvantage of anti balance tab
More effort is needed to deflect
