The Bell Boeing V-22 Osprey is an American multi-mission, military, tiltrotor aircraft with both a vertical takeoff and landing (VTOL), and short takeoff and landing (STOL) capability. It is designed to combine the functionality of a conventional helicopter with the long-range, high-speed cruise performance of a turboprop aircraft.

The V-22 originated from the United States Department of Defense Joint-service Vertical take-off/landing Experimental (JVX) aircraft program started in 1981. The team of Bell Helicopter and Boeing Helicopters was awarded a development contract in 1983 for the tiltrotor aircraft. The Bell Boeing team jointly produce the aircraft. The V-22 first flew in 1989, and began flight testing and design alterations; the complexity and difficulties of being the first tiltrotor intended for military service in the world led to many years of development.

The United States Marine Corps began crew training for the Osprey in 2000, and fielded it in 2007; it is supplementing and will eventually replace their Boeing Vertol CH-46 Sea Knights. The Osprey's other operator, the U.S. Air Force, fielded their version of the tiltrotor in 2009. Since entering service with the U.S. Marine Corps and Air Force, the Osprey has been deployed in both combat and rescue operations over Iraq, Afghanistan, Sudan and Libya.

Source: Wikipedia

Variants

V-22A 

Pre-production full-scale development aircraft used for flight testing. These are unofficially considered A-variants after the 1993 redesign.

CV-22B 

U.S. Air Force variant for the U.S. Special Operations Command (USSOCOM). It conducts long-range special operations missions, and is equipped with extra wing fuel tanks, an AN/APQ-186 terrain-following radar, and other equipment such as the AN/ALQ-211, and AN/AAQ-24 Nemesis Directional Infrared Counter Measures. The fuel capacity is increased by 588 gallons (2,230 L) with two inboard wing tanks; three auxiliary tanks (200 or 430 gal) can also be added in the cabin. The CV-22 replaced the MH-53 Pave Low.

MV-22B 

U.S. Marine Corps variant. The Marine Corps is the lead service in the V-22's development. The Marine Corps variant is an assault transport for troops, equipment and supplies, capable of operating from ships or expeditionary airfields ashore; replacing the Marine Corps' CH-46E and CH-53D fleets. The aircraft has received the latest modifications in the Block C upgrade.

EV-22 

Proposed airborne early warning and control variant. The Royal Navy studied this AEW variant as a replacement for its current fleet of carrier-based Sea King ASaC.7 helicopters.

HV-22 

The U.S. Navy considered an HV-22 to provide combat search and rescue, delivery and retrieval of special warfare teams along with fleet logistic support transport. It chose the MH-60S for this role in 2001. Naval Air Systems Command's 2011/2012 V-22 Osprey Guidebook lists the HV-22 for the U.S. Navy with the USAF and USMC variants.

SV-22 

The proposed anti-submarine warfare variant. The U.S. Navy studied the SV-22 in the 1980s to replace S-3 and SH-2 aircraft.