Block 2 Tilt Rotor Aerodynamics Flashcards
(41 cards)
What are the three modes of flight?
VTOL, Vertical Takeoff and Landing; CONV, Conversion; APLN, Airplane
Applying longitudinal stick causes pitch characteristics and airspeed changes similar to those in conventional helicopters.
Pitch
What are Nacelles used for?
- Accelerate or decelerate aircraft
- Select a desired pitch attitude while in a steady hover
- Adjust stick control margin
- Correct for extreme CG
- Recover from adverse flight conditions
What do forward nacelles produce?
Nose up attitude
What do Aft nacelles produce?
Nose down attitude
Location of the engines, prop rotors and gearboxes in the wingtip nacelles results in high inertia.
Roll
Axis inertia is high like the roll axis, but the yaw control power is less. Control is provided through the differential longitudinal cyclic.
Yaw
The ________ ___________ ________ (____) controls the overall thrust of the rotor system in a tiltrotor aircraft
Thrust Control Lever (TCL)
The Thrust Control Lever (TCL) in a tiltrotor aircraft ______ _____ operate in the same fashion as a typical helicopter collective controller
does not
Several design features have been incorporated in the software in tiltrotor aircraft to improve __________ ___________
vertical damping
For a tiltrotor aircraft, approximately _____ degree nacelles will generally give a level deck attitude on takeoff
90
During vertical takeoff to hover in a tiltrotor aircraft, _________ _________ is a decrease in power required at liftoff
ground effect
During vertical takeoff to hover in a tiltrotor aircraft, the power required ____________ with increasing altitude
increases
Aggressive pedal turns in tiltrotor aircraft should be ________ due to the high flapping associated with hovering turns
avoided
A ________ ________ _______ in a tiltrotor aircraft will require a roll angle into the wind
sideward hover taxi
________ ______ __________ refers to the pitch-up tendency of the aircraft when the empennage and horizontal tail are directly downwind of a prop rotor
Pitch-up with sideslip
Stick control margins in rearward flight can be increased with aft nacelles. In tiltrotor aircraft this is:
rearward hovering flight
During take off of a tiltrotor aircraft, ________ can be made from a hover if power available _______ power required for hover
departure
exceeds
During transition to forward flight as the aircraft builds airspeed and the nacelles continue their forward movement the control surface become _______ _______.
increasingly effective
_________ _________ is when power required decreases as forward airspeed increases wings provide lift.
Transitional lift
Approach to landing an increase in ________ will be required to maintain or arrest the decent.
Thrust Control Lever (TCL)
Vertical Landing is preferred to land with a _______ or ________ attitude.
Level or slightly nose-up pitch
Why is full aft nacelle vertical landing can be accomplished but is not recommended due to the ______ ______ _______ _______ attitude to touchdown .
Large nose down pitch
During take off of a tiltrotor aircraft, ________ can be made from a hover if power available exceeds power required for hover
departure