Sikorsky has officially unveiled its candidate for the US Army's Future Armed Reconnaissance Aircraft (FARA) programme, the Raider X. Over recent weeks, the FARA race has been prominent in aviation development news and Khalem Chapman explores the competition following Raider X's announcement.
The US-based helicopter manufacturer, a subsidiary of Lockheed Martin, introduced the Raider X on October 14 at the Association of the United States Army's (AUSA) annual conference in Washington DC, boasting that the aircraft will be "game changing" in technology and warfighting capabilities.
The Raider X employs technology gained in the development, testing and evaluation of the Sikorsky X2 experimental high-speed compound helicopter. It shares with this similar characteristics, including a coaxial rotor and smooth, blended fuselage design, plus retractable landing gear.
The Raider X is also similar to Sikorsky's S-97 Raider, the aircraft's predecessor upon which a lot of its technology and design is based. However, the Raider X is 20% larger than the S-97, a decision made to accommodate GE Aviation's T901-900 turboshaft engine, the US Army's desired powerplant.
Sikorsky boasts that the Raider X will have exceptional performance including enhanced low-speed hover, off-axis hover, plus highly responsive manoeuvrability, level acceleration and braking. These improved performance characteristics are provided by the X2 rigid rotor.
The company added that the aircraft will be designed digitally, in order to reduce acquisition costs along with being able to provide upgrades quickly and affordably. It will feature modern open systems architecture (MOSA) across its sensor, weapon and survivability avionics and mission systems. The firm also looks to reduce operating costs by using new technologies in order to transition from routine maintenance and inspections to self-monitoring and condition-based maintenance, making the aircraft more available for operational use and reducing maintenance periods. Sikorsky states that the Raider X will accommodate mission flexibility and aircraft development growth.
Aircraft in Sikorsky's X2 technology family have reached speeds in excess of 250kts (287mph/463km/h) and have operated at altitudes in excess of 9,000ft (2,743m). Aircraft have manoeuvred at more than 60 degrees angle of bank during low and high speed envelopes.
Frank St. John, executive vice president of Lockheed Martin Rotary and Mission Systems, said: "Raider X converges everything we've learned in years of developing, testing and refining X2 Technology and delivers warfighters a dominant, survivable and intelligent system that will excel in tomorrow's battlespace where aviation overmatch is critical... The X2 Technology family of aircraft is a low-risk solution and is scalable based on our customers' requirements."
The FARA programme intends to fill a capability gap left following the retirement of the Bell OH-58D Kiowa Warrior light observation, reconnaissance and attack helicopter fleet in 2017, a gap which is currently been covered by US Army Boeing AH64D Apache Longbow and AH-64E Apache Guardian attack helicopters. In total, the US Army awarded five companies with design contracts in April 2019. The current schedule for FARA will see just two companies proceed to develop airworthy prototypes of their proposed designs, with the US Amy due to make this decision by next March. By the end of 2023, these two aircraft will take part in a fly-off competition, with the results dictating which design/company will obtain the FARA contracts to produce the successor to the OH-58D.
AVX Aircraft/ L3 Communications
Unveiled in April 2019 – not long after the FARA contracts were officially awarded – was the Compound Coaxial Helicopter (CCH), submitted to the programme by AVX Aircraft and L3 Technologies. As with the Raider X, the CCH reconnaissance/light attack helicopter concept employs coaxial rotor technology and will feature MOSA-based avionics and digital systems, while maintaining systems commonality with other US Army capabilities. The design places the pilots side-by-side in the cockpit in order to make it more efficient and its small size, with folding wings and blades, will enable it to be easily transported by C-17s and for potential shipborne deployments. The aircraft itself is powered by a single engine and features wings to generate lift during high-speed forward flight. The company boasts that the CCH will meet 100% of the FARA requirements in this phase of the programme, seemingly confident of progression to the second phase.
When talking about the CCH, Christopher E Kubasik, chairman, CEO and president of L3 Technologies said: “This FARA-CP solution provides L3 and AVX an opportunity to demonstrate the agility and innovation that sets our team apart in support of the US Army’s modernisation priorities... We are collaborating to deliver a prototype that provides powerful leap-ahead capability for our warfighters at an affordable life-cycle cost.”
Bell/ Collins Aerospace
Bell has partnered with Collins Aerospace in offering its 360 Invictus to the US Army for its FARA programme. Unveiled on October 2, the Invictus is a militarised and smaller derivative of Bell's 525 Relentless commercial helicopter, which is currently in testing in the US. It also has a striking resemblance to the cancelled Boeing-Sikorsky RAH-66 Comanche stealth helicopter proposed at the turn of the century.
Along with the CCH, the Invictus is a winged helicopter but unlike the Raider X and AVX Aircraft/ L3 Technologies proposal it does not feature coaxial rotor technology. Its fuselage is sleek and blended with a retractable undercarriage, like the others. It also features internal weapon bays, an integrated munitions launcher, the capability for air-launched effects integration and a 20mm rotary cannon under the nose. Bell boasts that the Invictus, the name of which is Latin for 'unconquerable' or ‘undefeated', will exceed the US Army's FARA requirements, basing their top speed and statistics on those achieved by the 525 Relentless.
Kieth Flail, vice president of Advanced Vertical Lift Systems at Bell said: "Bell is committed to providing the US Army with the most affordable, most sustainable, least complex, and lowest risk solution among the potential FARA configurations, while meeting all requirements."
For more information on the Bell 360 Invictus, see our story on its unveiling here.
Karem Aircraft/ Northrop Grumman/ Raytheon
Also in October, Karem Aircraft, partnered with Northrop Grumman and Raytheon, unveiled the AR40 for the FARA programme. The aircraft also features wings and a blended fuselage design. These wings, however, are longer than the diameter of the helicopter's rotors, measuring 12.2m (40ft) with the rotors sitting at 11m (36ft). Along with other benefits, the wing is to generate larger amounts of lift when the aircraft is flying at high speeds.
A unique difference the single-engined AR40 has in comparison with other candidates is the aircraft's swivelling tail rotor, which will be angled backwards in forward flight, acting as a pusher propeller and giving the helicopter more aggressive manoeuvrability at lower speeds. In line with the Raider X and CCH, pilots will be seated side-by-side in the AR40, as opposed to the tandem-seating arrangement applied on the 360 Invictus. It will have internal weapon bays and room inside for the transport of up to four troops. Karem are confident that the AR40 will exceed the requirements set by the US Army for FARA candidates.
The AR40 sees its production and applications split between the three companies working together to produce it. Karem will be producing rotor and drive technologies for the aircraft, along with leading the developmental process with regards to the prototype and design. Northrop Grumman will be supporting the AR40 with avionics and production, while Raytheon develops the helicopter's MOSA-based mission systems integration.
Boeing is yet to formally unveil its candidate for the FARA programme. However, some in the industry have speculated that its compound Apache could be Boeing's potential pitch to the US Army for FARA. Something which has not being confirmed by Boeing executives.
With the FARA programme gathering pace, a lot of these concepts follow similar similarities, utilising blended, sleek fuselage designs with retractable undercarriages to increase speed and perhaps introduce elements of stealth to light attack/reconnaissance helicopters. The majority follow a side-by-side pilot seating configuration over the tandem-seat setup the Invictus employs. This type of configuration is commonly found in attack helicopters rather than previous iterations of light attack/reconnaissance helicopters, such as the OH-58D. The Invictus seems to follow a more basic helicopter design, featuring a traditional rotor instead of using coaxial technology and swivelling tail rotors. All but the Raider X seemingly employ fixed wings to help generate lift at high-speeds. Horizontal stabilisers seem prevalent with each concept too, less so on the AR40, with a single, large and more angled stabiliser on the left-hand side of the helicopter's tail. There are similarities with aircraft armaments too, using internal weapon bays alongside weapons deployable from hardpoints on the wings and undernose cannons.
With four of the five contracted companies having publicly revealed designs to the US Army's FARA competition, all eyes are now on Boeing to see what its official proposed candidate will be, and whether it will be a hugely modified Apache or an entirely new platform.