GUY NORRIS / INDIANAPOLIS

The US Air Force has unveiled a new supersonic global strike aircraft study and other concepts created as notional design drivers for a new generation of engines to be developed under the Versatile Affordable Advanced Turbine Engines (VAATE) programme.

The study includes a supersonic unmanned combat air vehicle (UCAV), an ultra-short take-off and landing intra-theatre transport, a versatile large aircraft, and other strike and rotary-wing platforms. VAATE follows the long-running Integrated High Performance Turbine Engine Technology (IHPTET) programme, which is near final tests.

VAATE focuses on giving higher engine capability at lower cost, and is aimed at a tenfold cost reduction, compared to engines with 2000 technology, by 2010 for VAATE 1 and 2017 for VAATE 2. Teams are identifying new features for two cores - a small one for helicopters, transports and unmanned aircraft, and a large core for fighters, bombers and large transports. These include mechanical systems, combustors, turbines, compressors and other sections and systems. First core engine run is due in 2006 with full engine run the following year.

Other key targets include a 20% thrust/weight increase and an 80% thrust/volume improvement. The USAF does not believe radically new technology, such as pulse detonation engine cores, are needed for VAATE 1 targets. These include a 20% and 40% cut in cost and specific fuel consumption for turbofans and turbojets respectively. Phase 2 is aiming for reductions of 25% and 60%.

The VAATE targets are being assessed against a Mach 2.4 global strike aircraft. The tailless concept aircraft is 38.4m (126ft) and incorporates thrust-vectoring control. With a 119,700kg (263,700lb) maximum take-off weight and a 9,250km (5,000nm) unrefuelled mission radius, it would have an 11.6h mission endurance against 27.2h for the Rockwell B-1 and 21.8h for the Northrop Grumman B-2. The VAATE-powered aircraft could reach 80% of notional targets with response time three times faster than current aircraft.

The VAATE-powered versatile large aircraft, a 67.7m semi-blended wing design with a deep fuselage, is designed to take a 68,100kg payload non-stop to destinations over 90% of the world - not possible with today's powerplants. The supersonic UCAV, with a gross weight of 6,110kg, is configured for M1.9 cruise at 40,000ft, and designed to carry a 1,360kg payload.

Source: Flight International