The United States Air Force (USAF) has approved Rolls-Royce to move to the next phase in developing a jet engine capable of high performance but with low operating costs.

The Pentagon’s decision to proceed with phase two of development of the Adaptive Versatile Engine Technology (Advent) is seen as a huge boost for Rolls-Royce in the lucrative American military market.

Its LibertyWorks division in the United States is working on jet engine technology that will provide high performance but is capable of shifting down to low speed and low fuel consumption. The USAF hopes that such engines will improve the operating performance of future manned and unmanned fighter aircraft and improve fuel consumption by about 25 per cent. The new technology will also have an impact in the commercial sector, where it could allow engines to give high thrust for take-off but then switch to a cruise mode that would be significantly more fuel efficient than the existing engines.

Rolls-Royce was awarded a $296 million contract by the Pentagon two years ago to develop Advent technology. The latest milestone is considered a key step in ensuring that the research reaches full production.

Phil Burkholder, the chief operating offficer of LibertyWorks, said: “We look forward to continuing our partnership on the Advent programme that will deliver a step-change in aerospace propulsion technology."

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