Imagine an aircraft that could take off and land like a helicopter but fly as fast as an airplane. You're thinking of Bell Boeing V-22 Osprey, the first tiltrotor aircraft to enter production and one of the most innovative (and controversial) machines of the modern era.
After a long and troubled development process, which included several notorious crashes that soured many people on the program, the Osprey eventually escaped its bad headlines and proved itself to the Pentagon. The V-22 has entered service with the U.S. Marine Corps and U.S. Air Force, and is set to join the U.S. Navy in the early 2020s. Its story is just beginning.
It Really Works
The dream of an airplane that could take off vertically and fly horizontally is decades old. In the 1950s, Bell Helicopter Textron flew the XV-3, an aircraft that placed its two Pratt & Whitney R-985 engines on wingtips. Positioned at the end of the wings, they could rotate 90 degrees to transition from takeoff/landing to forward flight.
The could fly up to 185 miles an hour, much faster than contemporary helicopters. Test pilots racked up 110 conversions from vertical to horizontal flight and back before one of the two aircraft was severely damaged in a wind tunnel accident.
Although that accident spelled the end of the program, the XV-3 had proven the tiltrotor concept was feasible. And after a long break, Bell followed up in 1977 with the . Unlike the XV-3, which housed the engine in the fuselage and ran a complex system of driveshafts the length of the wings to the rotating wingtip propellers, the XV-15 placed the turboshaft engines directly on the wingtips where the entire propulsion unit could be rotated from forward facing to straight upward. This was a lighter, less complicated solution to the tiltrotor issue and a significant step forward, freeing up space inside the aircraft to carry personnel and cargo.
An Aircraft Born of Failure
Meanwhile, the U.S. was facing the scourge of the Iran hostage crisis. The 1980 failure of Operation Eagle Claw, the failed hostage rescue mission, was partially attributed to the short range of U.S. military helicopters. The U.S. Navy RH-53D helicopters, required to fly from the aircraft carrier USS Nimitz in the Persian Gulf to the Iranian capital of Tehran, lacked the range to make a nonstop trip. Troops and aircraft would secretly secure an airstrip in the Iranian desert to refuel the helicopters and ensure they had enough fuel for their mission. It was a dangerous tactic. A collision between a C-130 Hercules and RH-53D at the refueling site caused the loss of aircraft and rescuers and forced the commander to abort the mission.
And so, in 1981, the Pentagon issued a requirement for a Joint Services Advanced Vertical Lift Aircraft (JVX). A long-range transport aircraft like JVX would have simplified the rescue process, allowing the rescuers to fly directly to Tehran and back without landing to refuel. In response to the military's request, Bell Helicopter Textron and Boeing Vertol proposed a tiltrotor aircraft with a substantial carrying capacity, speed, and range.
The Bell-Boeing won the contract for JVX in 1983. The aircraft was envisioned in multiple flavors: as a medium assault transport for the Marine Corps, replacing 1960s-era transport helicopters, s CV-22 special operations variant for the Air Force, a HV-22 logistics aircraft for the Navy, and a special mission electronics aircraft for the Army.
The first Osprey rolled out of Bell’s Flight Research Center in Arlington, Texas on May 23, 1988, and the V-22 program immediately ran into strong headwinds. The Cold War was winding down, and the defense budget was decreasing. Budget-cutters eyed the V-22 and said its mission could be accomplished by cheaper, traditional helicopters. Yet the aircraft survived numerous attempts to cancel it, even in the face of .
Today’s Osprey is a mature aircraft design that fulfills the Pentagon's decades-long vision. The Osprey is 57 feet long and 22 feet high with its engine nacelles rotated upward. In that position, with two sets of rotors side by side, it is more than 84 feet wide.
The plane is powered by two Rolls-Royce Liberty engines, each of which delivers 6,150 shaft horsepower/4,568 kilowatts. This allows the Osprey to carry a crew of four plus up to 24 personnel internally. Alternatively, the Osprey can carry up to 12,500 pounds in an external slung load, including artillery, wheeled vehicles, and supplies.
The Marine Corps version, the , can be loaded with 24 Marine combat troops in the back and fly at speeds of up to 240 knots (276 miles an hour). By contrast, the old CH-46E Sea Knight could only carry about 18 troops at 166 miles an hour. And the MV-22 has a longer range, allowing it to carry those troops up to 230 miles versus the CH-46E’s 186 miles. The MV-22 is also capable of in-flight refueling, giving it nearly unlimited range. In May 2015, four MV-22s self-deployed from the Japanese island of Okinawa in the Pacific to Nepal to assist in earthquake recovery efforts, covering a distance of more than 2,500 miles.
Today the U.S. Marine Corps has enough Ospreys to retire the Vietnam-era CH-46, and plans to field a total of 360. The U.S. Air Force currently has operational, with a requirement for 50 aircraft. The MV-22 and the CV-22 differ in only a handful of respects, mainly that the Air Force model carries an additional 304 gallons more fuel internally, giving it longer range but at a slightly slower cruising speed. The U.S. Navy, meanwhile, is planning to order to ferry cargo to and from shore from aircraft carriers, replacing the C-2A Greyhound. The CMV-22B will have even greater range, a high frequency beyond line of sight radio, and a public address system.
Both the MV-22 and CV-22 Ospreys have seen combat in Afghanistan, Iraq/Syria, and the Horn of Africa region. The aircraft is lightly armed, since the tiltrotor configuration prevents it from carrying side-mounted weapons like many traditional helicopters. The MV-22 Osprey has a provision for a M240B 7.62-millimeter machine gun or M2 .50 caliber heavy machine gun firing from out the back of the rear cargo ramp, while the CV-22 has a dedicated .50 caliber machine gun in the same position. A belly-mounted gun that can fire without risk of striking the aircraft is under development.
Despite a rocky, sometimes tragic start, the Osprey’s combination of speed, range, and vertical takeoff capability has won the tiltrotor concept a permanent place in aviation. The U.S. Army is now considering a similar tiltrotor, the V-280 Valor, to replace the UH-60 Blackhawk, and European aviation giant Leonardo is preparing a commercial tiltrotor, the . The Navy’s CMV-22Bs will enter service starting in 2020. Meanwhile, the Marines and Air Force will fly their Ospreys for several more decades.
Although rooted in the 1980s, the Osprey will serve the U.S. military well into the mid-21st century.