Click to enlarge The Bell V-280 Valor ” src=”https://cdn.arstechnica.net/wp-content/uploads/2019/02/Bell-V-280-Valor-640×346.jpg” width=”640″ height=”346″ srcset=”https://cdn.arstechnica.net/wp-content/uploads/2019/02/Bell-V-280-Valor-1280×692.jpg 2x”/>
The Bell V-280 Valor
Textron's Bell unit has already gotten its contender in the air. Bell's V-280 Valor, an evolution of the V-22 Osprey tilt-rotor, has been in flight testing for over a year. In January, the prototype V-280 reached 280 knots in flight. And Bell officials said that they expect the Valor to only get faster. The V-280 is expected to have a combat range of 920 miles (1480km) -nearly three times that of the Black Hawk.
The advantage of tilt-rotor aircraft is that they combine the vertical take-off and landing capabilities of and a helicopter with the flight characteristics of an airplane. And Bell has the advantage of having the Osprey to help it mature the technology. Early on, the Osprey-flown by the Marine Corps and Navy, was plagued with accidents and maintenance issues. But it has become much more reliable and is now being pressed into new missions by the Navy, including a heavy lift for carrier cargo deliveries
There are reasons the Osprey is not an Army favorite. One is that its entire wings – including the turbine engines that power the rotors-rotate, making the craft more expensive and complex and making landing zones more jet-blasted and dusty. The Valor fixes some of the challenges of the Osprey by tilting only its rotors and not the whole turbine engine assembly, meaning it will kick down the dust and not set fire to the grassy landing zones. It's also lighter and potentially cheaper than the V-22
The Sikorsky-Boeing SB-1 Defiant ” src=”https://cdn.arstechnica.net/wp-content/uploads/2019/02/defiant-640×360.jpeg” width=”640″ height=”360″ srcset=”https://cdn.arstechnica.net/wp-content/uploads/2019/02/defiant.jpeg 2x”/>
Enlarge / The Sikorsky-Boeing SB-1 Defiant
Sikorsky / Boeing
Bell's competitor in the competition is the Sikorsky-Boeing SB-1 Defiant. The Defiant is an evolution of the X-2 experimental helicopter and the S-97 Raider, both of which used rotors based on what Sikorsky called the Advancing Blade Concept, a design that uses counter-rotation rigid rotors for lift and a pusher propeller for much of the thrust. The design of the rigid propellers helps get past the aerodynamic issues that have limited helicopter speeds in the past.
The X-2, the first Advancing Blade Concept helicopter, unofficially broke the speed record for rotary-wing aircraft in 2010 by flying at 250 knots (287 miles per hour). The Raider, developed internally by Sikorsky, was originally targeted at the Army's Kiowa replacement effort-now the Future Attack Reconnaissance Aircraft program. It fits within the same footprint as the Kiowa but can carry up to six troops in addition to the pilot and the co-pilot
The Defiant has yet to fly-currently, its prototype is in ground testing. But the Raider has already flown and has reached cruising speeds of over 200 knots (by comparison, the Black Hawk's maximum speed is 159 knots, or 183 miles per hour.) When in a level flight, Raider behaves more like a commercial jet than a helicopter: the collective control locks in its most efficient position, and the pilot flies the helicopter exclusively with the cyclic stick. A control on the stick allows the pilot to control the pitch of the rear propeller and manipulate the speed in the level flight or to fly the aircraft backward with negative pitch. And the combination of rigid rotors and rear thrust makes Raider much more nimble than other helicopters.
The Raider is designed to withstand sustained forces of up to three times Earth's gravity in maneuvering-think Airwolf, without the 1980s soundtrack, fantastic Mach 1 speeds, and all-you-can-fire missiles.
Sikorsky is working on an updated Raider-like design for the Future Attack Reconnaissance Aircraft program that meets Army's new specifications. The Army is looking for an aircraft that has a maximum footprint of 40 feet in diameter – a bit larger than the Raider's 34-foot main rotor diameter.
Listing image by Textron Bell
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