|NASA Exploration Systems Progress Report||
Marshall Space Flight Center, Huntsville, Ala.
Status report: H-06-273
NASA engineers around the country recently completed tests associated with rocket engines, heat protection systems and spacesuits destined for use in the Constellation Program of moon and Mars missions.
Engineers at NASA's Marshall Space Flight Center, Huntsville, Ala., completed an early step in developing the upper-stage rocket engine that will be used in both the Ares I crew launch vehicle and the Ares V cargo launch vehicle.
The Marshall team completed the first series of tests on a scaled-down version of main injector hardware, which will inject and mix liquid hydrogen and liquid oxygen propellants in the engine combustion chamber, where they are ignited and burned to produce thrust.
The initial tests were performed on a hardware model, approximately 1/13th the thrust level of a full-scale J-2 engine injector, that contained 40 individual elements for propellant flow. The injector was fired horizontally with varying fuel temperatures and different propellant mixture ratios for 10 to 20 seconds at a thrust of approximately 20,000 pounds. Approximately 50 tests are planned for this series.
These tests will help engineers investigate design options for, and maximize performance of, the J-2X upper stage engine, an updated version of the powerful J-2 engine used to launch the Saturn V rocket upper stages during Apollo.
At Johnson Space Center, Houston, recent tests focused on materials that could be used to protect the Crew Exploration Vehicle when it makes its fiery descent through the atmosphere on the way home to Earth.
Engineers used an arcjet facility capable of simulating re-entry temperatures to test eight tile samples. Four tests evaluated the performance of LI-2200, a dense silica fiber tile that has been used on the belly of the space shuttle to protect it during atmospheric re-entry. Also tested was the BRI-18, which flew for the first time this month on parts of the Space Shuttle Discovery. The BRI-18 is a stronger tile that can be protected with a more durable coating for better protection against damage from debris.
Also in Houston, astronauts and other personnel practiced walking back to base from a stranded moon rover to test basic spacesuit requirements for use in designing the first new spacesuit for use on the moon since Apollo. These suits will need to be more comfortable and durable than earlier spacesuits since the next lunar explorers will be staying on the surface for longer periods, eventually up to six months at a time, and conducting more scientific research and construction tasks than ever attempted in Apollo.
The tests used an advanced spacesuit in simulated lunar and Mars conditions, one-sixth and one-third Earth's gravity respectively.
Using a treadmill and wearing a spacesuit designed to test various components, seven people completed the tests at speeds ranging from 2.75 to 5.5 mph. In all, the subjects covered 61.25 miles, more than the total 59.6 miles covered by all 12 Apollo moon walkers.
At Stennis Space Center near Bay St. Louis, Miss., test conductors fired an Integrated Powerhead Demonstration engine at the 100-percent power level for the first time. The engine is a ground demonstrator engine combining the very latest in rocket engine propulsion technologies.
The engine uses liquid oxygen and liquid hydrogen. It is being developed and tested as a re-usable engine system, capable of up to 200 flights. The project is a combined effort by Pratt and Whitney Rocketdyne, Inc. Canoga Park, Calif., and Aerojet, Sacramento, Calif., under the program direction of the Air Force Research Laboratory, Edwards, Calif., and technical direction of Marshall.
Constellation's Ares I and Ares V launch vehicle project includes teams at NASA and organizations around the nation. The project is led by the agency's Exploration Launch Projects office at Marshall. The Constellation Program Office and Crew Exploration Vehicle Project Office are hosted by the Johnson Space Center.
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