Lockheed Martin may be forced to replace the composite propellant tanks of the X-33 technology demonstrator with aluminium tanks, delaying the first launch until 2002. The company is also investing a further $100 million in the programme, which should have seen a first launch last June.
The composite tanks have been posing difficulties for some time and, in November, a liquid hydrogen tank was damaged during a pressure test.
The switch to aluminium tanks, which will be used on the proposed VentureStar single-stage-to-orbit re-usable launch vehicle, will make the X-33 heavier. Its flight-test speed and altitude profile will inevitably be degraded, leading some observers to question the point of the demonstrator.
Source: Flight International
