Seaplane UAV, small gunship, transatmospheric vehicle and heavylift STOL/VTOL transport in US agency’s plans

Concepts ranging from an optionally manned small gunship to a global-range transatmospheric vehicle are among new programmes the US Defense Advanced Research Advanced Research Projects Agency (DARPA) plans to launch in fiscal year 2007.

Demonstrations of a high-lift wing using distributed embedded propulsion for circulation control and a low-drag swept wing with passive laminar flow control are other projects for which DARPA is seeking initial funding in its FY2007 budget request.

New programmes for 2007 include the Dual Mode Small Gunship, an existing low-cost small aircraft modified to carry sensors and weapons that can be controlled either remotely from the ground or by an on-board crew. Controlled directly by troops on the ground, the aircraft will provide a persistent strike capability, with the ability to have a pilot on board for deployment and safe operation over populated areas.

Technology for a short/vertical take-off and landing aircraft – also optionally manned – able to carry a 20t payload over a radius of at least 740km (400nm) at more than 200kt (370km/h) will be demonstrated under the Heavy Lift programme. An amphibious unmanned aircraft able to loiter at sea for several days, then take off and land in high seas is the concept behind the agency’s Seaplane UAV project.

DARPA’s Close Air Support Technology for Loitering Engagement programme will explore persistent, survivable unmanned aircraft able to provide precision fire support on demand using electromagnetic guns, directed-energy weapons, vertical-launch missiles, or “deep magazine” conventional guns and bombs. The Aircraft Self Protection project, meanwhile, will look at active defence of slow-moving high-altitude aircraft using missiles or high-energy lasers.

Under the Global Range Transatmospheric Vehicle programme, DARPA plans to develop a turbine-based combined cycle propulsion system combining an expendable Mach 4 turbojet with a reusable M7+ supersonic-combustion ramjet. The agency’s goal is to enable a future large-scale hypersonic cruise X-plane demonstration.

Among other new programmes for which funding is requested, the distributed embedded propulsion project will windtunnel- or flight-test a fully coupled engine/wing design using propulsive flow over the surface for circulation control to increase lift. Potential applications include short take-off and landing aircraft and high aspect-ratio flying wings.

Also planned is the flight demonstration, at subsonic and supersonic speeds, of a laminar-flow swept wing using “innovative” passive control of crossflow instabilities to delay the transition to turbulent flow, reducing drag.

Funding is also sought to test a propulsive anti-torque system on a Bell AH-1Z, re-engine the Boeing A160 helicopter UAV with the Pratt & Whitney Canada PW207 turboshaft, test a tethered ducted-fan UAV for operations in “urban canyons” and design an oblique flying wing demonstrator.


Source: Flight International