Funds diverted from upgrades will pay for accelerated deployment of combat SAR force

The US Air Force has revealed further details of an accelerated plan to deploy a next-generation combat search-and-rescue (CSAR) helicopter force through an effort that will defer most high-risk development work until the programme's final stages (Flight International, 2-8 March).

Created in January, the service's Personnel Recovery Vehicle (PRV) programme office hosted an industry day in Dayton, Ohio on 4 March, during which chief engineer and acting programme manager Ronald Vokits said: "Now is the time to identify what is doable and what is not." Requirements trade-offs are still being considered, he says.

The programme office plans to release a draft solicitation containing a tentative list of requirements on 8 June, with a formal request for proposals to follow within a further 10 months. Air force acquisition documents call for a contract award for up to 132 aircraft in March 2006, with the Lockheed Martin/AgustaWestland US101, NH Industries NH90 and Sikorsky S-92 considered likely to compete for the project.

The USAF plans to achieve initial operational capability with 18 aircraft in a Block 0 configuration by fiscal year 2011, followed by a more advanced Block 10 design to be delivered from 2014. The aggressive pace is supported by halting upgrades to the existing Sikorsky HH-60G Pave Hawk fleet and diverting those funds to the PRV programme. The air force also hopes to achieve the Block 0 schedule by deferring several advanced PRV capabilities, particularly in propulsion.

Requested aircraft speed during phase one of the PRV development plan should range between 135kt (250km/h) and 185kt in environmental conditions ranging from normal weather at sea level to hot-day conditions at 6,000ft (1,830m). In phase two, however, this is projected to jump to a baseline of 200kt, with an objective goal of 300kt. This "may require new technology", says Vokits.

Boeing and Sikorsky have already proposed concept designs for helicopters that could achieve such speeds, but these involve largely untested canard rotor/wing and reverse-velocity rotor technologies. The air force has identified propulsion among six technology risk areas, and its phase two requirement for an unrefuelled combat radius of 325-450km (175-240nm) could also rely on design efficiencies being tested under the US Army's ongoing Improved Turbine Engine Programme.

The avionics suite should include the CSAR fleet's existing forward-looking infrared sensor and weather radar, plus a global air traffic management system, software-defined radios, improved electronic warfare and countermeasures equipment, a precision location system, head-up display and a terrain-following/terrain avoidance radar. Its structure must be capable of surviving battle damage and power-out landings, and refuelling must be completed within 10min, says the air force.


Source: Flight International