Block 2 Tilt Rotor Aerodynamics

Question 1

What are the three modes of flight?

Answer 1

VTOL, Vertical Takeoff and Landing; CONV, Conversion; APLN, Airplane

Question 2

Applying longitudinal stick causes pitch characteristics and airspeed changes similar to those in conventional helicopters.

Answer 2

Pitch

Question 3

What are Nacelles used for?

Answer 3

1. Accelerate or decelerate aircraft
2. Select a desired pitch attitude while in a steady hover
3. Adjust stick control margin
4. Correct for extreme CG
5. Recover from adverse flight conditions

Question 4

What do forward nacelles produce?

Answer 4

Nose up attitude

Question 5

What do Aft nacelles produce?

Answer 5

Nose down attitude

Question 6

Location of the engines, prop rotors and gearboxes in the wingtip nacelles results in high inertia.

Answer 6

Roll

Question 7

Axis inertia is high like the roll axis, but the yaw control power is less. Control is provided through the differential longitudinal cyclic.

Answer 7

Yaw

Question 8

The ________ ___________ ________ (____) controls the overall thrust of the rotor system in a tiltrotor aircraft

Answer 8

Thrust Control Lever (TCL)

Question 9

The Thrust Control Lever (TCL) in a tiltrotor aircraft ______ _____ operate in the same fashion as a typical helicopter collective controller

Answer 9

does not

Question 10

Several design features have been incorporated in the software in tiltrotor aircraft to improve __________ ___________

Answer 10

vertical damping

Question 11

For a tiltrotor aircraft, approximately _____ degree nacelles will generally give a level deck attitude on takeoff

Answer 11

90

Question 12

During vertical takeoff to hover in a tiltrotor aircraft, _________ _________ is a decrease in power required at liftoff

Answer 12

ground effect

Question 13

During vertical takeoff to hover in a tiltrotor aircraft, the power required ____________ with increasing altitude

Answer 13

increases

Question 14

Aggressive pedal turns in tiltrotor aircraft should be ________ due to the high flapping associated with hovering turns

Answer 14

avoided

Question 15

A ________ ________ _______ in a tiltrotor aircraft will require a roll angle into the wind

Answer 15

sideward hover taxi

Question 16

________ ______ __________ refers to the pitch-up tendency of the aircraft when the empennage and horizontal tail are directly downwind of a prop rotor

Answer 16

Pitch-up with sideslip

Question 17

Stick control margins in rearward flight can be increased with aft nacelles. In tiltrotor aircraft this is:

Answer 17

rearward hovering flight

Question 18

During take off of a tiltrotor aircraft, ________ can be made from a hover if power available _______ power required for hover

Answer 18

departure

exceeds

Question 19

During transition to forward flight as the aircraft builds airspeed and the nacelles continue their forward movement the control surface become _______ _______.

Answer 19

increasingly effective

Question 20

_________ _________ is when power required decreases as forward airspeed increases wings provide lift.

Answer 20

Transitional lift

Question 21

Approach to landing an increase in ________ will be required to maintain or arrest the decent.

Answer 21

Thrust Control Lever (TCL)

Question 22

Vertical Landing is preferred to land with a _______ or ________ attitude.

Answer 22

Level or slightly nose-up pitch

Question 23

Why is full aft nacelle vertical landing can be accomplished but is not recommended due to the ______ ______ _______ _______ attitude to touchdown .

Answer 23

Large nose down pitch

Question 24

During take off of a tiltrotor aircraft, ________ can be made from a hover if power available exceeds power required for hover

Answer 24

departure

Question 25

A vertical landing with a nose gear first-contact can be safely accomplished by ____________ _______ prior to touchdown.

Answer 25

Minimizing drift

Question 26

In CONV mode, the use and effect of flight controls will vary with _________ ________

Answer 26

nacelle angle

Question 27

As the nacelles rotate into CONV mode, the corresponding increase in airspeed allows the FCS to respond to pilot inputs using the ________, ________ and _________ to a greater degree than in VTOL

Answer 27

elevator
flappers
rudders

Question 28

______ ________ (___) is used in high altitude, high density, heavy weight where a VTOL can’t be done

Answer 28

Short Takeoff (STO)

Question 29

The Nacelle angle chosen for a short takeoff (STO) is:

Answer 29

nominally 60-75 degrees

Question 30

Under most conditions, there is no requirement to _______ _______ ______ for short takeoff, although this will generally reduce the ground roll distance

Answer 30

rotate the nose

Question 31

As the nacelles are rotated toward the downstops in CONV mode the aircraft transitions to wing-borne flight and the ________ ________ becomes more consistent

Answer 31

pitching effect

Question 32

During transition, maintaining a level _________ ________ and letting the ________ accelerate the aircraft gives the best results

Answer 32

pitch attitude

nacelles

Question 33

During transition use _____ ________ ___________ to maintain pitch attitude due to thrust and CG effects

Answer 33

aft stick movement

Question 34

_____________ ____________ (____) may be necessary at decreased power margins or preferred in the presence of certain aircraft malfunctions

Answer 34

Run-on landing (ROL)

Question 35

In APLN, CV-22 has flight characteristics similar to __________ ___________ ________

Answer 35

multi-engine turboprop aircraft

Question 36

In APLN mode, power setting and aircraft attitude determine __________

Answer 36

performance

Question 37

________ (________, ________, _________) principle is used for basic air work

Answer 37

P.A.T. (power, attitude, trim)

Question 38

The effect of pitch-power coupling increases with ____ ____________ and _______ ____________

Answer 38

low airspeed

high GW

Question 39

Adjust the ______ to negate any pitch coupling effects

Answer 39

stick

Question 40

In pitch coupling with rolling maneuvers, commands are phased out as bank angle increases beyond ____,. This is due to the ________ and ________ of the engines

Answer 40

30 degrees
weight
placement

Question 41

The FCS limits the aircrafts ability to reach the angles of attack at which ________ _______ could be encountered while maneuvering at high speed and altitude

Answer 41

empennage buffet