Gale Schluter, Boeing Vice-President for Expendable Launch Vehicles told the Senate Commerce and Science Committee in Washington that the research has been in engines and advanced materials, what Schluter called "the backbone of RLV development."

The admission marked the first time Boeing has confirmed it was interested in developing an operational reusable space launch vehicle, and was spending serious company money on the idea.

"We at Boeing see reusable launch vehicles as the long-term solution to space access and the true means to realize the potential of space-enabled telecommunications solutions," Schluter said Thursday.

Sources told SpaceDaily late Thursday Boeing was working with its Rocketdyne division on potential engine designs for a future launcher system.

The work was considered long range and represented a "major slice of Boeing space-related R&D," the source said. Schluter would not give any greater details of his company's RLV work. "We aren't ready to bring any RLV to market. But we are clearly seeking leadership in this field," he said.

Boeing was also working on a reusable lifting body crew return craft, the X-37, and was partner with Lockheed on the Space Shuttle United Space Alliance contract. Schluter reminded the Senate that the Shuttle was still "an operational reusable space vehicle".

Boeing's history also included a winged spacecraft design of the 1960's and 1970's called StarRaker. Research into the project was folded into the company's bid for the 1990 Strategic Defense Initiative launcher program that eventually became the Delta Clipper - won ultimately by McDonnell Douglas, with whom Boeing merged in 1997.