Item 1622
DESIGN:
AeroVantage ~ PropRotor - Outside Information - BA609, V-22 and V-44 (quad) TiltRotors
Craft:
& some information
- Transcendental Model 1-G:
- Disk loading: 3.6 lb/ft2
Transcendental Model 2:
Disk loading: 4.4 lb/ft2
Bell XV-3:
Disk loading: 5.3 or 5.66 lb/ft2
XV-15:
Disk loading: 10.3 or 13.2 lb/ft2
V-22:
Disk loading: 23.2 lb/ft2
BA609:
Disk loading: lb/ft2
Eagle Eye: Disk loading: 12.5 lb/ft2
Disk loading: lb/ft2
See; DESIGN: AeroVantage ~ PropRotor - Outside Information - Eagle Eye 916 (918) TiltRotors
V-44 (quad):
Disk loading: lb/ft2
For more see; DESIGN: AeroVantage ~ PropRotor - Outside Information - General Overview
Notes:
The V-22 Osprey V-22 and the Bell-Agusta BA609 tilt-rotors have fast cruise speeds, but are lacking in payload capacity. The problem is that the PropRotors have a fixed diameter. The disk areas are too small to provide a low disk loading during hover and too large to provide high-induced velocities during cruise.
Tip Speed:
- Helicopter mode: 790 ft/s ~ 772 fps [0.71M]
- Propeller mode: 662 ft/s ~ 641 fps [0.59M]
Twist: The V-22 has 47-degree rotorprop blade twist.
Control: The V-22 is a fly-by-wire aircraft with triple-redundant flight control systems. With the nacelles pointing straight up in conversion mode at 90° the flight computers command the aircraft to fly like a helicopter, with cyclic forces being applied to a conventional swashplate at the rotor hub. With the nacelles in airplane mode (0°) the flaperons, rudder, and elevator fly the aircraft like an airplane. This is a gradual transition, which occurs over the entire 96° range of the nacelles. The lower the nacelles, the greater effect of the airplane-mode control surfaces.
Blades: Bell-Boeing 901 V-22 Osprey Blade Root ~ XN28/XN18/XN12 Tip ~ XN09
Much information on V-22 Qsprey
Related Articles Etc:
Eagle Eye Pocket guide GW = 1960 lb., Rotor dia. = 10 ft., Cruise speed = 200 kts+
Aerodynamic Optimization of a Coaxial PropRotor Have Hard copy.
An Experimental Investigation of Ground Effect on a Quad Tilt Rotor in Hover and Low Speed Forward Flight https://drum.umd.edu/dspace/bitstream/1903/4094/1/umi-umd-3879.pdf Saved as Quad_Rotor_Testing.pdf in Stick
On page 22 it says "The rear wing is slightly longer and higher than the front wing, and the rear rotors are outboard of the front rotors for higher performance and fuel economy in cruise." Why will this give better performance in cruise over having the fore and aft rotors coaxial???
On page 24 it says "Previous studies on conventional tilt rotors have indicated a large download penalty on the wings while operating in hover,"
ACTIVE AND PASSIVE TECHNIQUES FOR TILTROTOR AEROELASTIC STABILITY AUGMENTATION A Thesis
AERODYNAMIC INTERFERENCE EFFECTS ON TILYNG PROPROTOR AIRCRAFT
AIRLOADS MEASUREMENTS FROM A 1/4-SCALE TILTROTOR WIND TUNNEL TEST Have hard copy.
Overview of the Testing of a Small-Scale Proprotor
Effects of Swept Tips on V-22 Whirl Flutter and Loads
Information on the V-22 blades ~ Calculation of the Aerodynamic Behavior of the Tilt Rotor Aeroacoustic Model (TRAM) in the DNW Saved in E-drive as Johnson_AHS01
Performance and Design Investigation of Heavy Lift Tiltrotor with Aerodynamic Interference Effects Have hard copy.
- Notes:
- The rotors rotate with the top blades moving outward in airplane mode. "This observation, the reduction of wing drag due to the favorable rotor swirl provided by the up-inboard rotating rotors, ...." It appears that this is done so that the upward swirl pushs lift under the wing while the downward swirl is not associated with a wing. This swirl relationship with the wing may also be beneficial during hover.
Flight Controls ~ V-22 Osprey:
The V-22 has both conventional airplane and conventional tandem rotor helicopter control surfaces. The primary flight controls consist of cyclic sticks located in front of each pilot, thrust control levers (TCLs) mounted to the left of each seat, and floor-mounted directional pedals. These controls are part of a fully digital, electronic, fly-by-wire system. Because the system is completely digital, the V-22 flight control system offers exceptional flexibility to incorporate the actuator control command for both fixed wing and rotary wing control surfaces and provides a smooth transition between helicopter and airplane flight modes.
The proprotor controls respond to cyclic, directional, and thrust lever inputs in helicopter and conversion modes, and to thrust inputs alone in airplane mode.
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Airplane Controls
- Full-span control surfaces
- Combination flap/aileron (flaperon)
- Rudder
- Elevator
- Proprotor pitch controlled automatically though TCL input
- Reduces flapping
- Maintains constant RPM
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Helicopter Controls
- Proprotor blades are primary flight control
- Thrust Control Lever (TCL) is throttle and collective pitch
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Extensive research has been performed using pilot simulation to design an intuitive and comfortable set of cockpit controls. The figures below illustrate the effects of each pilot control input on aircraft motions in both helicopter and airplane modes.
Forward Stick Input
Aft Stick input
Left Stick Input
Right Stick Input
Left Pedal Input
Flap Input
Right Pedal Input
Thrust Power Input
PropRotor Head ~ BA 609:
DESIGN & DEVELOPMENT OF THE BA 609 CIVIL TILTROTOR HYDRAULIC SYSTEM ARCHITECTURE Have hard copy.
Technical Specifications:
See;
DESIGN: AeroVantage ~ PropRotor - Outside Information - General Overview
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Last Revised: February 17, 2009