The U.S. Army will soon have to make major decisions regarding its rotorcraft acquisition strategy.
The big overarching question: Will the service overcome previous procurement pitfalls associated with the RAH-66 Comanche — a $7 billion program cancelled by the Army in 2004?
The challenges are prima facie, as the service has not fielded a new helicopter design since the 1980s — a lack of new fielded designs that is also reflected in the commercial world, as the Bell 525 Relentless is thus far the only design of the last decade that appears close to fielding.
The Comanche had its beginnings in the Light Helicopter Experimental (LHX) program, launched in 1982 to replace a number of service helicopters, including the OH-58, OH-6, UH-1 and AH-1.
The Army wants to get the front end of its future helicopter program right this time around so that the service can get new, advanced helicopters in the field by 2028.
The Pentagon FY2020 budget request includes about $790 million for Future Vertical Lift (FVL) research and development. That includes about $94 million for FVL technology under basic research and $152 million for FVL advanced technology.
The Army's significant budget request for FVL may allay the fears of some in industry about sustaining the Joint Multirole Technology Demonstration (JMR-TD) program and moving it forward into FVL. For JMR-TD, which is to end this year, the Bell V-280 Valor tiltrotor is competing against the Boeing-Sikorsky built SB-1 Defiant. Industry and government have funded the two demonstration aircraft at a ratio of about two-to-one.
The V-280 flew for the first time in December, 2017 and achieved forward flight of 280 knots in January this year, while the SB-1 is to use two coaxial rigid rotors for lift and a variable-pitch pusher prop for airplane-like speed.
Unveiled last December, the Defiant is expected to make its first flight before the middle of this year.
The Army is seeking to replace at least 4,000 aging helicopters, and both Bell and Sikorsky/Boeing hope their respective designs are selected to fulfill FVL Capability Set 3 — the future long-range assault aircraft (FLRAA) — to replace the Sikorsky UH-60 Black Hawk. The Marine Corps, which heavily employ the Bell-Boeing V-22 Osprey, may also be a customer of the V-280.
The Army has conducted an Analysis of Alternatives (AoA) on FLRAA by using the Black Hawk and various UH-60 upgrades, including the Improved Turbine Engine Program and main rotor and tail rotor enhancements.
Army leaders may finalize the results of the AoA by this summer.
“Before JMR-TD, the industrial base had not designed a new Army rotorcraft in a couple of decades,” said Dan Bailey, the program manager of JMR-TD and the Future Attack Reconnaissance Aircraft competitive prototype (FARA CP) at U.S. Army Futures Command. “JMR-TD was squarely about bringing those companies back up to speed for the environments predicted in the future.”
“The biggest challenge area in the latest design efforts is in the generational evolution since the 1970s and 1980s to the 2010-plus time frame,” he said. “Think about computers and computer- aided design and modeling. None of that was around in the 1970s and very little in the 1980s.”
The low-fidelity computer modeling of the 1980s and scale model testing worked well for determining performance of isolated components — rotors, fuselage — but proved less accurate when those components were scaled up and tested together. Comanche worked well when scaled down, but the operational prototype had issues with the main rotors interacting with the fan tail, which required a full redesign 17 years into the program.
Companies in JMR-TD are using the Army-funded Helios code and other software programs to improve their modeling of aircraft performance in simulation before bending metal.
In the days of yore, the Army and industry used to come up with different results from their paper designs, but tools, like Helios, help to ensure that government and company engineers are on the same page.
“We’ve overcome that [analog design] problem with JMR-TD, and that postures us for executing FVL without the hiccups we saw with Comanche,” Bailey said.
Another key issue, of course, is funding. Will the Army call for enough to sustain rotorcraft technology advancement efforts by companies, as the latter have committed to investing two to three times what the Army does in JMR-TD?
For their part, Textron and Bell executives have said that their internal investment in the V-280 will likely end this year without new funding from the Army.
FVL/JMR-TD is third on the list of the Army’s most important modernization programs, and Army long-range budget plans call for $2.4 billion in FVL research-and-development over five years.
The Future Attack Reconnaissance Aircraft (FARA) — FVL Cap Set 1 — is also in the Army’s future rotorcraft mix, as FARA would fill the role once played by the OH-58D Kiowa warrior and not necessarily replace the AH-64E Apache that is now flying armed scout missions.
The Army kicked off the FARA competition last October — a solicitation that lays out a four-phase competitive prototyping effort that should yield operational, experimental aircraft flying by November 2022.
The FARA competition will likely be stiff. In February, Airbus said that it is offering a concept based on the company’s Rapid and Cost-Effective Rotorcraft (RACER) aircraft that should fly 50 percent faster than a traditional helicopter while burning 25 percent less fuel.
Proposals for the initial design review phase of FARA were due in December and Airbus has submitted its information, if not necessarily plans for a complete operational prototype. That puts it in the running with Sikorsky’s S-97 Raider or some variation of the compound helicopter, an as-yet unrevealed Bell offering likely based on its V-280 Valor advanced tiltrotor and a joint proposal from L3 and AVX Aircraft Company, which is also under wraps.
Not to be outdone, MD Helicopters has said that it is developing “Swift,” a new, all-composite, winged version of its 969 twin-engine attack aircraft. “Swift” will use MD’s no-tail-rotor (NOTAR) technology and will fly at up to 200 knots, according to the company — squarely in the Army’s desired capability range for FARA. This June or July, the Army plans to contract between four and six manufacturers to participate in a nine-month initial design review phase. From that group, two companies will move on to build competing demonstration aircraft, essentially participating in a "fly-off" for the Army and then one or both will be further contracted to enter an engineering and manufacturing development phase.
Flight testing is slated to begin in 2023, and the Army is to make a down-select decision in 2024.