Funding cuts by lawmakers have doomed a hypersonic project named Blackswift that was to develop a long-awaited successor to the Lockheed SR-71 Blackbird.

The fiscal 2009 defence budget approved last month slashes requested spending for the Mach 6-capable Blackswift Test Bed project from $120 million to $10 million.

The combined-cycle Blackswift demonstrator was scheduled to complete first flight in 2012. It should have reached a top speed of Mach 6 using a combination of a turbojet and a supersonic combustion ramjet (scramjet). As a reusable aircraft, it should have been able to land and be ready to fly again after refuelling.

 Source: Flickr

The original request included a $70 million contribution from the Defense Advanced Research Projects Agency (DARPA) and $50 million from the US Air Force.

Blackswift was championed by former USAF chief of staff Gen Michael Moseley, who was fired by Secretary of Defense Bob Gates in June.

In a statement, DARPA said it would "not be possible" to continue the solicitation process with the available funding. Boeing and ATK and teamed up with Lockheed Martin’s Skunk Works team to submit a bid. Northrop Grumman had not confirmed whether it intended to submit a competing offer.

"Obviously, we are disappointed that we will not have the appropriated funds to move forward with the Blackswift flight test program," said Steven Walker, DARPA programme manager.

"A significant effort was put forward over the last several years to develop the propulsion technology required and to build a national government and industry team capable of developing and flying a reusable hypersonic testbed," Walker added.

The focus of hypersonics research will shift to focusing on supporting existing programmes.

The DARPA/USAF Falcon programme awarded to Lockheed will proceed with fabricating hypersonic technology vehicles that will begin flight tests in 2009.

See the DARPA/Lockheed hypersonic Falcon video:

Meanwhile, a Boeing/Pratt & Whitney Rocketdyne team is aiming to fly the airbreathing X-51 Waverider hypersonic cruise missile in late 2009 and early 2010.

That programme is sponsored by DARPA, the air force research laboratory and NASA.The Boeing hypersonic HyFly programme has also been extended.

See DARPA's video:

DARPA and the Office of Naval Research agreed last month to provide funds to conduct a third test flight after the first two attempts failed for causes unrelated to hypersonic technology.

The Blackswift Test Bed, meanwhile, will remain on DARPA’s shelf of discarded technologies, but Walker is still hopeful that it could re-emerge.

Walker also hinted that competition from a rival power could eventually re-awaken interest in Blackswift."It was a good idea and good ideas have a way of coming back and getting done eventually," he said.

"Hopefully, the US will do it first, but there are no guarantees."