By Kris Osborn
The Army is preparing for the first official flights of two high-tech, next-generation aircraft now being designed with a wide range of abilities to include flying faster, flying farther without needing to refuel, operating in high-hot conditions and having an ability to both reach high speeds and hover like a helicopter.
The new aircraft are part of an Army-led effort, called Joint Multi-Role Technology Demonstrator, aimed at paving the way toward ultimately engineering a new fleet of aircraft for all the services to take flight by 2030.
“These are next-generation aircraft. These are new configurations,” Dan Bailey, JMR TD program director, told Scout Warrior.
While some of the eventual requirements for the new aircraft have yet to be defined, there are some notional characteristics currently being sought after by the program. They include an ability to travel at airplane-like speeds greater than 230 knots, achieve a combat radius of 434 kilometers, use a stronger engine and operate in what’s called “high-hot” conditions of 6,000-feet and 95-degrees Fahrenheit.
“We had set 230 as the speed requirement because we wanted to push the technology. We wanted people to bring new ideas and new configurations to the table,”
A faster, more manueverable helicopter that can fly farther on one tank of fuel would enable forces in combat to more effectively engage in longer combat operations such as destroying enemy targets or transporting small groups of mobile, lethal ground fighters. The new helicopter will also be designed to use next-generation sensors to find enemies on the move and employ next-generation weapons to attack them, Army officials describe.
The JMR TD technology effort will inform a planned program of record called Future Vertical Lift, or FVL, which will design, build and test a series of next-generation aircraft for the Army, Navy, Air Force and Marine Corps.
“FVL is a high priority. We have identified capability gaps. We need technologies and designs that are different than what the current fleet has. It will carry more equipment, perform in high-hot conditions, be more maneuverable within the area of operations and execute missions at longer ranges,” Rich Kretzschmar, project manager for the FVL effort, told Scout Warrior in an interview.
The first flights of the demonstrator aircraft, slated for 2017, will include developmental helicopter/aircraft from two industry teams – Bell Helicopter and a Sikorsky-Boeing team.
The Bell offering, called the V-280 Valor, seeks to advance tilt-rotor technology, wherein a winged-aircraft with two rotor blades over each wing seeks to achieve airplane speeds and retain an ability to hover and maneuver like a helicopter.
Bell’s V-280 recently finished what’s called a system-level design review where Army and Bell developers refine and prepare the design of the air vehicle.
“They have an air vehicle concept demonstrator that they call the third-generation tilt-rotor. Their fuselage was completed and it is being delivered to Bell for the build-up of the aircraft,” Bailey said.
Along with Boeing, Bell makes the V-22 Osprey tilt-rotor aircraft which is currently praised by military members for its excellent operational performance in recent years. The Osprey has two rotating rotor blades which align vertically when the aircraft is in helicopter mode and then move to a horizontal position when the aircraft enters airplane mode and reaches speeds greater than 280 knots.
The V-280 Valor also has two propellers which rotate from horizontal airplane mode to a vertical position, which allows for helicopter mode. Bell officials have said their new aircraft will be able to reach speeds of 280 knots. Bell and Army officials explain that their V-280 Valor substantially advances tilt-rotor technology.
“What Bell has done is taking its historical V-22 aircraft, and all the demonstrators before that, and applies them to this next-generation tilt-rotor. It is a straight wing versus a V-22 which is not straight. This reduces complexity,” Bailey explained. “They are also building additional flapping into the rotor system and individual controls that should allow for increased low-speed maneuverability.”
The Sikorsky-Boeing demonstrator, called the SB>1 Defiant, uses a coaxial rotor system configuration. This is a design structure, referred to as a compound configuration, which relies upon two counter-rotating rotor blades on top of the aircraft and a thrusting mechanism in the rear.
“To make a rotorcraft go fast you have to off-load the rotor lift onto something else or else you run into problems when you try to reduce the speed of that rotor. Typically, you do that with a wing but Sikorsky-Boeing came up with a lift-offset design,” Bailey added.
The pusher-prop on the back of the aircraft is a small propeller behind the counter-rotating rotor heads. It is what can give the aircraft airplane-like speeds. It operates with what’s called positive and negative pitch, allowing the aircraft to lean up or down and move both forwards and backwards, Boeing officials have said.
The JMR TD program and the follow-on FVL effort will also integrate a wide range of next-generation sensors, weapons and avionics, Army officials explained.
Bailey said both the Bell and Sikorsky-Boeing designs appear to be buildable.
In addition to conducting the first official Army-industry flight of the two demonstrators, the program will conduct what’s called a Milestone Development Decision, which will begin to pave the way for the FVL acquisition program. This effort will conduct a thorough examination of all the available technologies and their performance through what is called an “analysis of alternatives.”
A key advantage of a joint FVL program is that it will engender further inter-operability between the services and, for example, allow an Army helicopter to easily be serviced with maintenance at a Marine Corps Forward Operating Base, Bailey explained.
