V-22 Osprey in flight.
The V-22 Osprey is an American joint service, military tiltrotor aircraft with the V/STOL capability. V/STOL stands for Vertical/Short Takeoff and Landing. It is deisgned to operate like a conventional helicopter, but with the long-range, high-speed cruise performance of a turboprop aircraft.
Development...
The Department of Defense began the V-22 program in 1981, first under Army leadership, then the Navy/Marine Corps later took the lead in developing what was then known as the Joint-service Vertical take-off/landing Experimental (JVX) aircraft. Full-scale development of the V-22 tilt-rotor aircraft began in 1986.
The V-22 was developed and is built jointly by Bell Helicopter, which manufactures and integrates the wing, nacelles, rotors, drive system, tail surfaces, and aft ramp, as well as integrates the Rolls-Royce engines, and Boeing Helicopters, which manufactures and integrates the fuselage, cockpit, avionics, and flight controls. Portions of the aircraft are manufactured in Philadelphia, Pennsylvania, Grand Prairie, Texas, and Fort Worth, Texas. Final assembly and delivery occurs in Amarillo, Texas. The joint development team is known as Bell Boeing. The first of six MV-22 prototypes first flew on March 19, 1989 in the helicopter mode and on September 14, 1989 as a fixed-wing plane. The third and fourth prototypes successfully completed the Osprey's first Sea Trials on the USS Wasp in December 1990. However, the fourth and fifth prototypes crashed in 1990-91. Flight tests were resumed in August 1993 after changes were incorporated in the prototypes.
Flight testing of four full-scale development V-22s began in early 1997 when the first pre-production V-22 was delivered to the Naval Air Warfare Test Center in Patuxent River, MD. The first EMD Flight took place on February 5, 1997. The first of four low-rate initial production aircraft, ordered on April 28, 1997, was delivered on May 27, 1999. Osprey number 10 completed the program's second Sea Trials, this time from the USS Saipan in January 1999. During external load testing in April 1999, Boeing used a V-22 to lift and transport the M777 howitzer.
In 2000 there were two further fatal crashes, killing a total of 19 marines, and the production was again halted while the cause of these crashes was investigated and various parts were redesigned.
The V-22 completed its final operational evaluation in June 2005. The evaluation was deemed successful; events included long range deployments, high altitude, desert and shipboard operations. It was claimed that the problems identified in various accidents had been addressed by the V-22 program office.
On September 28, 2005, the Pentagon formally approved full-rate production for the V-22. The plan was to boost production from 11 a year to 24 to 48 a year by 2012. Planned production quantities include 360 for the Marine Corps, 48 for the Navy, and 50 for the Air Force. The U.S. Army, originally the lead service for the then-named JVX program, is a possible candidate for use.
The V-22 had a flyaway cost of $70 million per aircraft in 2007, but the Navy hopes to shave about $10 million off that price after a five-year production contract starts in 2008.
A total of 458 V-22s are expected to be built for the Marines, U.S. Air Force and U.S. Navy at an average unit cost of $110 million per aircraft.
Israel has shown interest in the purchase of an undisclosed number of MV-22s, but an order has not been placed or approved.
U.S. Marines jump from a V-22 Osprey.
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Design...
The Osprey is the world's first production tiltrotor aircraft, with one three-bladed proprotor, turboprop engine, and transmission nacelle mounted on each wingtip. For takeoff and landing, it typically operates as a helicopter with the nacelles vertical (rotors horizontal). Once airborne, the nacelles rotate forward 90° in as little as 12 seconds for horizontal flight, converting the V-22 to a more fuel-efficient, higher-speed turboprop airplane. STOL rolling-takeoff and landing capability is achieved by having the nacelles tilted forward up to 45°. For compact storage and transport, the V-22's wing rotates to align, front-to-back, with the fuselage. The proprotors can also fold in a sequence taking 90 seconds.
The V-22 is equipped with a glass cockpit, which incorporates four Multi-Function Displays (MFDs) and one shared Central Display Unit (CDU), allowing the pilots to display a variety of images including: digimaps centered or decentered on current position, FLIR imagery, primary flight instruments, navigation (TACAN, VOR, ILS, GPS, INS), and system status. The flight director panel of the Cockpit Management System (CMS) allows for fully-coupled (aka: autopilot) functions which will take the aircraft from forward flight into a 50-foot hover with no pilot interaction other than programming the system.
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.
The Osprey is armed with one 0.308 in (7.62 mm) machine gun pointing rearward that can be fired when the loading ramp is lowered. A GAU-19 three-barrel 0.50 in (12.7 mm) gatling gun mounted below the V-22's nose has also been studied for future upgrade. BAE Systems is also developing a remotely operated turreted weapons system for the V-22.
Operational History...
USMC crew training on the Osprey has been conducted by VMMT-204 since March 2000. On 3 June 2005, the Marine Corps helicopter squadron HMM-263, stood down to begin the process of transitioning to the MV-22 Osprey. On 8 December, 2005, Lieutenant General Amos, commander of the 2nd Marine Expeditionary Force, accepted the delivery of the first fleet of MV-22s, delivered to HMM-263. The unit reactivated on 3 March 2006 as the first MV-22 squadron and was redesignated VMM-263. On 31 August 2006, VMM-162 (the former HMM-162) followed suit. On March 23, 2007, Marine Medium Helicopter Squadron 266 became Marine Medium Tiltrotor Squadron 266 (VMM-266) at Marine Corps Air Station New River, North Carolina.
he Air Force's first operational CV-22 Osprey was delivered to the 58th Special Operations Wing (58th SOW) at Kirtland Air Force Base, New Mexico on 20 March 2006. This and subsequent aircraft will become part of the 58th SOW's fleet of aircraft used for training pilots and crewmembers for special operations use.
On 10 July, 2007 an MV-22 Osprey landed aboard the Royal Navy aircraft carrier, HMS Illustrious in the Atlantic Ocean. This marked the first time an MV-22 had landed on any non-US vessel.
The Osprey entered operational service with the Marine Corps in 2007, in some cases replacing existing CH-46 Sea Knight squadrons. On 13 April, 2007 the United States Marine Corps announced that it would be sending 10 V-22 aircraft to Iraq, the Osprey's first combat deployment. Marine Corps commandant, Gen. James Conway, indicated that over 150 Marines would accompany the Osprey set for September deployment to Al-Asad Airfield. On 17 September 2007, 10 MV-22Bs of VMM-263 left for Iraq aboard the U.S.S. Wasp. The decision to use a ship rather than use the Osprey's self-deployment capability was made because of concerns over icing during the North Atlantic portion of the trip, lack of available KC-130s for mid-air refueling, and the availability of the U.S.S. Wasp.
The Osprey has provided support in Iraq, racking up some 2000 flight hours over three months with a mission capable availability rate of 68.1% as of late January 2008. They are primarily used in Iraq's western Anbar province for routine cargo and troop movements, and also for riskier "aero-scout" missions. Gen. David Petraeus, the top U.S. military commander in Iraq, used one to fly around Iraq on Christmas Day, 2007, to visit troops. The only major problem has been obtaining the necessary spare parts to maintain the aircraft.
Specifications
General Characteristics...
Crew: two pilots
Capacity: 24 troops (seated), 32 troops (floor loaded) or up to 15,000 pounds of cargo
Length: 57 ft 4 in (17.5 m)
Rotor diameter: 38 ft 0 in (11.6 m)
Wingspan: 46 ft (14 m); 84 ft 7 in (including rotors))
Height: 22 ft 1 in (overall - nacelles vertical) (17 ft 11 in 5.5 m (at top of tailfins))
Disc area: 2,268 ft² (212 m²)
Wing area: 301.4 ft² (28 m²)
Empty weight: 33,140 lb (15,032 kg)
Loaded weight: 47,500 lb (21,500 kg)
Max takeoff weight: 60,500 lb (27,400 kg)
Powerplant: 2× Rolls-Royce Allison Rolls-Royce T406 (AE 1107C-Liberty) turboshafts, 6,150 hp (4,590 kW) each.
Performance...
Maximum speed: 275 knots (316 mph, 509 km/h)
Cruise speed: 214 knots (246 mph, 396 km/h) at sea level
Range: 879 nmi (1,011 mi, 1,627 km) (unrefueled)
Combat radius: 370 nmi (430 mi, 690 km)
Ferry range: 2,417 nm (2,781 mi, 4,476 km)
Service ceiling: 26,000 ft (7,925 m)
Rate of climb: 2,320 ft/min (11.8 m/s)
Disc loading: 20.9 lb/ft² @ 47,500 lb GW (102.23 kg/m²)
Power/mass: 0.259 hp/lb (427 W/kg.).
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