The Clinton Administration is to request money in next year's budget for NASA to start a five-year programme to develop technology for a next-generation reusable launch vehicle (RLV).
NASA has concluded that "the current commercial market and the state of technology are not sufficiently favourable to enable private-sector development of second-generation RLV without government cost-sharing", chief engineer Daniel Mulville told Congress last week.
Instead, the agency plans to spend more than $5 billion over the next five years to prepare for a competition in 2005 to select a vehicle that will replace the Space Shuttle. That contest is expected to pit a Shuttle-derived vehicle against a new RLV.
Mulville says NASA is working with the Administration's Office of Management and Budget to draw up an investment plan that would "maintain competition and reduce the risk associated with developing second-generation RLV architectures by 2005".
The plan is to include upgrades to the Shuttle, another RLV technology demonstrator comparable to the Lockheed Martin X-33 and other smaller flight-test vehicles similar to the Orbital Sciences X-34 and Boeing X-37.
The programme will also pave the way for third-generation RLVs, which will offer safety and reliability comparable to airliners.