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Forget Airwolf: One of these is the Army's next assault "helicopter"



The Army's future "helicopter" takes shape.

The Sikorsky UH-60 Black Hawk and its many variants have been the backbone of the US Army's helicopter force for decades. Designed during the Army's last major helicopter procurement push in the 1980s, the Black Hawk now flies in some form in all of the military services. But its range and speed have become limiting factors in the Army's airborne assault operations. And to add to the problem, the Army lacks a scout helicopter that meets the demands of deployment overseas. The Eurocopter UH-72 Lakota is not capable of fighting, so AH-64 Apaches has played the role of armed scouts with the help of drones.

As a result, the Army has two separate helicopter procurement programs running for the first time since the Black Hawk and Apache were in the pipeline. The two programs, which emerged from the "capability sets" of the Army's Future Vertical Lift program, seek Black Hawk and Kiowa replacements that are "optional manned" ̵

1; meaning that they can fly with or without an aircrew-as well as being easier to

The Black Hawk replacement competition, which the Army is now calling the Future Long Range Assault Aircraft program, is the most fully formed of the two so far, with two contenders already in the prototype phase. The goal of the program is a flight that is faster, longer ranged, more lethally armed, stealthier, more rugged, and more agile than the Black Hawk, while at the same time being more intuitive to fly. And it should be affordable.

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”/>
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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