SpaceX Falcon 9 Static Fire Test Nears

SpaceX 

Challenged by an unprecedented series of “firsts” for its upcoming initial flight of Falcon 9 with a Dragon spacecraft, Space Exploration Technologies (SpaceX) stresses that even if the vehicle is not recovered intact as planned, the mission should be judged an overall success.

Unlike the first successful launch of its Falcon 9 launch vehicle in June with a representative Dragon, the planned flight in early December will launch an operational spacecraft to low Earth orbit. After as many as four orbits, the plan is for Dragon to reenter Earth’s atmosphere and be recovered by parachute en route to a splashdown in the Pacific off the California coast.

Flight 2 of the Falcon 9 is also the first demonstration flight under NASA’s Commercial Orbital Transportation Services (COTS) program, a critical milestone on the path established in 2006 to encourage private companies to develop commercial space transport capabilities, and to resupply the International Space Station (ISS) starting in 2011. The Dragon is designed to return as much as 5,510 lb. of cargo back to Earth, well in excess of any other commercial cargo supply system.

The second flight also will be the first test of the Dragon’s operating system, heat shield and Draco maneuvering thrusters. The flight represents the first processing of hypergolic fuels for those thrusters on the launch pad, as well as the first time an FAA-licensed commercial space company has attempted to bring a spacecraft back through Earth’s atmosphere. And the flight marks SpaceX’s first interaction with the Dragon spacecraft from its newly opened mission control center in Hawthorne, Calif.

The launch attempt of the Falcon 9/Dragon combination itself remains a significant achievement, says SpaceX CEO and Chief Technical Officer Elon Musk. “It will be the first time any commercial company has tried to recover something from orbit. Only a handful of governments have succeeded in doing that,” he adds. Given the number of firsts involved in the deployment and recovery of the Dragon, Musk concedes that “there’s maybe a 60 to 70% chance of Dragon coming back fully intact, so when you multiply those probabilities [including an 80-90% launch success], then there’s maybe a 60% chance of success for the mission as a whole.”

However, even if Dragon is lost, Musk says each completed element of the mission will be a valuable contribution to the COTS demonstration. “There are graduations of success. It’s more information we’ll learn about the functioning of Falcon 9,” he says. “The reason we’re doing this mission is to learn. There’s no operational payload.”

The vehicle is being readied for launch at Cape Canaveral, Fla., and is scheduled for a final static firing test around Dec. 3. Pending a successful test, and no impact on range and recovery vessel availability caused by the slippage of the space shuttle launch, the earliest window opens Dec. 7.

Production items are also stacking up at Hawthorne for Flight 3, and a few for Flight 4, two COTS demonstrations scheduled for 2011. In mid-November, Aviation Week viewed at the SpaceX facility the sub-assemblies and parts for future Falcon 9 missions, including a first-stage engine truss, a single first-stage tank section undergoing friction-stir welding and a yet-to-be-completed composite inter-stage. The facility also housed numerous pressure domes—some are allocated for Flight 4—as the Dragon used for the successful Aug. 12 drop test, another Dragon under construction and a nose cone mold. Eight Merlin 1C engines were also awaiting integration into the first-stage truss. “We have just about finished the engines for Flight 3, and the engine parts for Flight 4. They’ve all been made and are going through testing now,” says Musk. “Anything at a component level is for Flight 4.”

Commenting on the relatively small number of assemblies in the factory, and SpaceX’s ability to meet demand for the follow-on COTS missions, Musk adds, “We’re not production constrained, the constraint is more on finalizing the engineering, finalizing the testing and passing the ISS safety review.” As these demonstrations require formatting and docking with the ISS itself, “there is lots of external validation and verification to occur. Their safety reviews are super hard core and pretty darn intense. If something goes wrong, you destroy a $100-billion asset and lives of astronauts.”

From purely a production perspective, SpaceX “feels confident it could be ready to launch [Flight 3] around late spring next year,” says Musk. However, if design changes are required because of the safety review or lessons learned from Flight 2, these would be minor changes to Dragon rather than the launch vehicle, he adds. Changes have been incorporated in the next Falcon 9 as a result of experience gained with the first vehicle. These include modifications to counter the roll seen on lift off. Calibration devices “were not properly calibrated, so all the engines had a slight amount of roll,” says Musk.

 

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