Flight-testing of the problem-stricken Alliant Techsystems Outrider tactical unmanned air vehicle (UAV) has resumed, with a strong endorsement from a senior US Department of Defense (DoD) procurement official, despite the threat of cancellation hanging over the programme.

The first of the additional flights, which took place on 3 June at Hondo, Texas, lasted about 7 min. The Outrider's third flight test included racetrack patterns, to assess handling qualities with the drone's new 4m-span wing and strengthened landing gear.

The test flight was followed by another on 4 June, which was cut short because of concerns over engine performance. The pace of test flights will now accelerate, as the company hopes to head off the Outrider's cancellation.

Those test flights will not include evaluation of a heavy-fuel-engine (HFE), however.

Poor performance of the Outrider's intended HFE has forced the Pentagon to persevere with gasoline powerplants for now.

In mid-April, the DoD began to seek alternatives to the Outrider, and gave Alliant Techsystems two months to solve nagging technical problems. The Outrider was six months late in being flown, its weight has been increased by 24% and its endurance cut by one-third.

US Navy Rear Admiral Barton Strong, head of the Pentagon's UAV Joint Project Office, is "quite optimistic" that the Outrider's problems have been resolved. "We had start-up problems, as every UAV has had, but we've worked through them pretty well," he says.

"The plan is to go with the Outrider…it is highly likely that it is going to be successful. If not, we will get into new UAV programmes," says Strong.

In beating eight other bidders, Alliant Techsystems proposed an HFE-powered drone. A modified four-stroke engine, converted to use diesel fuel, failed endurance testing. As a result, the HFE-powerplant will not be flight tested during the Outrider demonstration.

Strong says that no HFE is available, despite engine manufacturer's claims.

Source: Flight International