COLORADO SPRINGS, Colo. — While it does not yet have the necessary funding , NASA is considering building spare turbo pumps and other J-2X upper-stage engine hardware to prevent a test-stand mishap from further delaying the Ares 1 rocket’s arrival on the launch pad.
Doug Cooke, NASA deputy associate administrator for exploration systems, said during a panel discussion here April 10 that development of the upper-stage engine — an updated version of the Apollo-heritage J-2 engine — is the most technically challenging aspect of the Ares 1 program and thus a central driver that will determine when the rocket is ready to enter service launching the Orion Crew Exploration Vehicle.
NASA had at one time hoped to field the space shuttle replacement as early as 2011, but budget issues have forced the agency to push that date back to 2015. Agency officials say it would still be possible to meet a 2013 date if the program gets more funding in the near term.
Meeting with reporters earlier in the day, Cooke said to prevent any J-2X testing setbacks from holding up development of Ares 1, NASA is trying to find money to build spares for turbo pumps and other components that could be damaged or destroyed in such incidents.
“What you don’t want to have is a project that is so thin on the test hardware that you have a failure and then you are down for months or a year because you don’t have anything to go replace it and you have to go and build another part. We’re working on trying to make that more robust than initially it was laid out,” Cooke said.
Cooke said NASA has not made a final decision on what additional J-2X hardware, if any, it would order. “We’re not finalized on that yet,” he said.
NASA awarded Canoga Park, Calif.-based Pratt & Whitney Rocketdyne a contract last year to build five J-2X development engines followed by two certification engines to demonstrate performance and lifetime limitations. The first hot-fire test of a complete engine is on track for 2010 at NASA’s Stennis Space Center in Mississippi, according to Walt Janowski, Rocketdyne’s J-2X program manager.
While the J-2X was chosen in part because of its human spaceflight heritage, Cooke told reporters that the pedigree will not exempt the engine from a rigorous test program to prove its readiness to launch astronauts.
“It’s got enough in modifications [that] were going to have to do full testing on it,” Cooke said. “There’s no doubt about that.”
Recognizing how tricky developing a new engine — or modifying an existing one — can be, NASA continues to study backup options for the Ares 1 upper stage should it encounter insurmountable problems with the J-2X.
“We have looked at possible backups but those are still in study right now,” Cooke said. “The primary path we want to stay on is J-2. We’re doing everything we can to make that robust.”
Cooke acknowledged that one of the engines getting a second look is the space shuttle main engine. NASA initially planned to use a modified version of that engine for the Ares 1 upper stage, but decided in 2005 to go with the J-2X since it also could be used for the Moon-bound upper stage NASA would need for the heavy-lift Ares 5 rocket.
Cooke said NASA remains confident in the J-2X and said that there was not much of an effort being put into the analysis of alternatives.
“It’s actually kind of a ‘back burner’ kind of look at this point,” he said.
During the panel discussion, in which Cooke was joined by the executives of three firms helping NASA develop its new human space transportation system, the assessment of technical progress on both Ares 1 and Orion was upbeat.
Michael Kahn, vice president of space launch systems at Alliant Techsystems, outlined the hardware and tooling the company is building in preparation for a scheduled 2009 flight test of a four-segmented version of the Ares 1 main-stage booster, dubbed Ares 1-X. That test will be followed later that year by a hot-fire test of a five-segmented version of the solid rocket booster. Alliant Techsystems Launch Systems Group of Brigham City, Utah, is prime contractor on the Ares 1 main stage.John Karas, vice president and general manager for space exploration at Denver-based, the Orion prime contractor, said that effort is making steady progress. He highlighted the spacecraft’s multi-engine launch abort system as the so-called critical path item pacing Orion’s development.
He said subscale tests of the launch abort system, being developed by Dulles, Va.-based Orbital Sciences Corp. under subcontract to Lockheed Martin, would begin in less than a year with full-scale test slated to commence in about two years.