With Few Army Aviation Opportunities in Sight, Industry Targets R&D Programs
By Valerie Insinna
Once again, it is a quiet year for Army aviation at the Association of the U.S. Army annual meeting and exposition.
With no upcoming new-start aviation programs in the years ahead, industry is focused on science and technology programs that could improve future helicopters' capabilities including range, speed and payload.
The Army recently announced Bell Helicopter and a Sikorsky-Boeing team will design, build and fly joint multirole demonstrator aircraft capable of flying 230 knots — about 30 knots faster than a UH-60 Black Hawk utility helicopter.
Since their selection, the companies are finalizing designs ahead of the critical design review next summer, executives from Bell and Sikorsky-Boeing said at the conference. Both contractors will fly aircraft in fiscal year 2017.
Bell is offering the V-280 Valor tiltrotor, a clean-sheet design that applies some of the lessons learned while building the V-22 Osprey, said program manager Keith Flail.
Boeing-Sikorsky is building the SB>1 Defiant, a coaxial helicopter featuring counter-rotating rigid main rotor blades on top and a pusher propeller in the rear.
“Right now we’re already practicing bending metal. We’re doing some manufacturing risk reduction elements … on our rotor blades, which will be composite,” said Pat Donnelly, one of Boeing-Sikorsky’s program managers.
The 2017 flight demonstrations will not end with the Army signing on to purchase a new fleet of aircraft. Rather, the new aircraft will help inform requirements for a program of record called future vertical lift — a family of rotorcraft that will replace most of the Army’s helicopter fleet. The medium-lift FVL variant is expected to enter service as early as 2034 and would replace Boeing’s AH-64 Apache and Sikorsky’s UH-60 Black Hawk.
Army officials have disclosed preliminary FVL requirements relating to speed, range and payload. The joint multirole effort is only concerned with one of those — speed — but companies are working to meet as many requirements as possible during the demonstrator program.
The Defiant will exceed the Army’s 230-knot speed requirement and is projected to cruise at 250 knots, said Doug Shidler, Boeing-Sikorsky’s other program manager. It can carry 12 troops and a four-person crew. The SB>1 will be able to operate at altitudes of 6,000 feet in 95-degree Fahrenheit temperatures — a 2,000 foot increase over the Black Hawk. The companies will also leverage composite materials and fly-by-wire technology.
The only future vertical lift requirement the aircraft falls short on is range, Donnelly said.
"Since we're using off the shelf engines we just don't have the fuel efficiency that's projected for future vertical lift, so we're not going to have the range that they're looking for,” he said. The Defiant is equipped with a T55 turboshaft engine, which is also used on the CH-47 Chinook cargo helicopter.
The aircraft is sized to meet the 424-kilometer range requirement listed in the Army’s broad area announcement, Shidler said. Boeing-Sikorsky expects the Defiant will be able to fly that distance once it is equipped with the service’s future affordable turbine engine, which is being developed by General Electric.
Meeting the future vertical lift range requirement will not be a problem for Bell Helicopter’s V-280, Flail said. For the demonstrations, the tiltrotor will be powered by the GE Aviation T64 used in the Marine Corps’ CH-53E Super Stallion cargo aircraft, and it will also be able to accommodate the future affordable turbine engine.
The Valor will fly at a cruise speed of 280 knots and be able to carry 14 troops and a four-person crew, he said. It has a fly-by-wire flight control system that prevents the pilot from overturning the propellers when it’s decelerating and accelerating.
One of Bell’s goals is to reduce the Valor’s cost, weight and complexity, Flail said. Although the Army has not set a cost target for future vertical lift, the company has set its own goal — “significantly less than half the cost of a V-22 for this capability,” he said.
Bell designed the V-280’s wings to be perfectly straight and they will be manufactured completely from composite materials, which reduces cost and weight, he said.
Helicopters typically have a higher cost-per-flying-hour than fixed wing airplanes because there is added stress on the dynamic components of most rotorcraft, Flail said. Because a tiltrotor can take off vertically, but fly horizontally like an airplane, stress is reduced and operating and support costs are lowered.
“If you advanced technologies without looking at it through an affordability lens, what’s the point, if you’re making a technology that no one can afford?” he asked. “That’s where we have that benefit of understanding how tiltrotors behave and really attacking the affordability while at the same time increasing performance.”
Boeing-Sikorsky’s 30,000-pound Defiant is derived from Sikorsky’s X2 demonstrator aircraft, which weighed about 6,000 pounds, but Shidler stressed that scaling up the aircraft is more involved than simply sizing up all of its components.
“You need to optimize for speed, you need to optimize for hover performance,” he said.
The companies could not simply increase the size of the X2’s transmission, for example, and expect it to perform the same, Donnelly said. The team designed a transmission together, conducted a “fairly exhaustive” trade study, “and came up with what we believe is … a very weight efficient transmission design.”
Exactly how “joint” the JMR and FVL will be is up for debate. The Navy has expressed interest in acquiring a maritime version of the latter aircraft. The Defiant will have manually folding blades so it can be stowed on a ship, Shidler said.
Boeing-Sikorsky receives its feedback from the Army, but Donnelly is seeing more interest from the other services, he said.
“Up until now, most of the services have been fairly quiet, but now they’re stepping up as the JMR is becoming more real, and they’re being more vocal,” he said.
AUSA 2014 marked the second year in a row the service’s program executive office for aviation held no press briefings.
PEO Aviation’s decision to sit out the conference was not surprising given the events over the past year. Lt. Gen. Kevin Mangum, formerly commander of the Army Aviation Center of Excellence and Fort Rucker and now deputy commanding general of Training and Doctrine Command, announced in January that the Army did not have enough money to procure an armed aerial scout to replace the OH-58 D Kiowa Warrior reconnaissance helicopter.
Not only did the service have to eliminate its only initiative for procuring new rotorcraft, budget constraints forced it to cut its entire fleet of Kiowa Warriors and TH-67 trainers in the fiscal year 2015 budget submission.
Instead, the service is investing in modernization initiatives that can stretch the service lives and capabilities of its aircraft. One such program is the improved turbine engine program, a 3,000 shaft horsepower engine that will double a Black Hawk’s range and the number of troops it can carry in high altitudes and hot temperatures.
The Advanced Turbine Engine Co., a joint venture of Pratt & Whitney and Honeywell, announced yesterday that its second engine completed durability, performance and sand testing, said its president Craig Madden.
GE Aviation finished its second engine testing earlier this year, said Michael Sousa, Jr., GE Aviation’s product development manager for new and derivative products.
Both companies have designed and produced two new engines under the Advanced Affordable Turbine Engine science and technology program. The AATE effort allowed the companies to mature technologies before the ITEP program of record launches. A request for proposals from the Army is expected for ITEP sometime next year, Madden said.
“Our understanding is the Army would intend to take two competitors to Milestone B … just after preliminary design review,” said Jerry Wheeler, ATEC’s vice president of programs. After that, the service would downselect to one competitor.
Despite budget cuts, both ATEC and GE Aviation officials expressed confidence that the ITEP program would be protected.?
“Maj. Gen. [Mike] Lundy, the new aviation branch chief, has come on board, and this is his number one Army aviation modernization priority,” Madden said. “He’s very supportive because this engine improves the warfighter capability.”
GE Aviation is developing the future affordable turbine engine, or FATE, in a five-year science and technology effort similar to AATE, Sousa said. The company completed a detailed design review last year for a FATE engine with 5,000 to 10,000 shaft horsepower and is now testing components. GE expects to test two engines before the program ends in 2016.
So far, there is no concrete plan to build FATE into a program of record, but the Army could require a similar engine for certain future vertical lift variants, Sousa.
“What you really want if you’re developing that brand new aircraft for the future and its going to be around for the next 50 years, is you want an engine that gives you the technology that’s appropriate with that new aircraft,” he said. “The challenge we have today is knowing exactly where the requirements for FVL will be versus where JMR is today and … the physical size it needs to be.”
Madden believes the light or medium future vertical lift aircraft could incorporate ITEP, depending on requirements, he said.
“If it’s in a similar weight range as today’s Black Hawk or Apache, then the ITEP engine is sized to power that,” he said. “The ITEP engine is also scalable to higher powers if needed to fill in a gap in the shaft horsepower range.”
Topics: Aviation, Rotary Wing