Tim Furniss/LONDON
THE UPRATED McDonnell Douglas (MDC) Delta Clipper-Experimental Advanced (DC-XA) prototype launcher had its first test flight from White Sands, New Mexico, on 18 May.
The 12.8m-high vehicle was flown to an altitude of 800ft (240m), powered by its four liquid-oxygen/liquid-hydrogen (LOX-LH) engines and was manoeuvred 105m sideways, before being flown back to its launch pad.
The vehicle hovered over the pad longer than was originally planned, and deflected flames from the engines ignited a brief fire on the side of the DC-XA.
The damage was slight and the second test in the five-flight series has been scheduled for 7 June, when the vehicle is expected to reach 2,000ft.
The test flights, which end in July, are part of a NASA programme to develop the technologies needed for the proposed X-33 re-usable launcher (Flight International, 20-26 March, P5).
"Flight testing will provide information about the performance of composite materials and other advanced technologies in the launch vehicle as it encounters the conditions of flight, such as temperature, pressure and noise," says NASA programme manager Dan Dumbacher.
The DC-XA is a modified version of the MDC DC-X, initial trials of which were completed in July 1995 after eight flights dating from August 1993.
Its airframe has been modified extensively, making it 635kg lighter than the original. Modifications include a composite LH tank. The 18 May launch was the first by a rocket with such a component, according to MDC.
Other new items include a Russian-built aluminium-lithium alloy LOX tank, a composite intertank to connect the LOX-LH tanks and an auxiliary propulsion system, including a composite LH feedline, LH valve and a liquid-to-gas conversion system for reaction control.
The vehicle also includes a Russian auxiliary power unit providing redundant hydraulic power for flight control.
Source: Flight International