The Apollo programme-derived Pratt & Whitney Rocketdyne 294,000lb (1,308kN) thrust J-2X engine that will power the upper stages of NASA's Ares rockets could use a French nozzle cone if Safran's Snecma Propulsion Solide proposal wins the contract later this year.

Snecma Propulsion Solide is involved in technical discussions with P&WR, NASA's J-2X prime contractor, about the French company's commercial proposal to develop the new engine's composite nozzle cone. If the company wins the contract, it will be the first major non-US-sourced component for NASA's new space transportation system.

The Safran subsidiary has expertise in composite cones - the technology the J-2X is likely to use - and has developed nozzles for the operational EADS Astrium Ariane 5 and ELV Vega, which is yet to fly. The P&WR RL10 engine, which powers Boeing's Delta II and IV rockets, also uses Snecma Propulsion Solide's nozzles.

The J-2X, described by NASA as "a new engine", will use the gas generator and turbopumps from the Apollo's Saturn V second-stage J-2 engine and make use of developments from the 1970s J-2S version. A single J-2X will power NASA's Ares I crew launch vehicle's upper stage and the Ares V cargo launch vehicle's Earth departure stage.

"We are waiting for the preliminary design review, which will be this month or February," says Snecma Propulsion Solide. "At the present time, we are discussing with P&WR the technical and commercial offer. But we don't have any contract with them."

According to NASA's October 2007 multi-programme integrated milestones schedule, the J-2X PDR was to occur in the third quarter of that calendar year. Like the Ares I first-stage PDR, the J-2X PDR has slipped more than six months.

But last month, cold-flow testing of the J-2X powerpack, the J-2 gas generator and turbopumps, which perform the engine's major pumping and combustion work, began at NASA's Stennis Space Center. Testing will continue through February and will include test-fires at a variety of power levels and durations from 12s to 550s. The first full hot fire test of the J-2X is planned for 2010.

Source: FlightGlobal.com

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