SpaceX Successfully Tests New Rocket's Engines at Launch Pad

A brand-new Falcon 9 rocket envisioned to launch cargo ships to the International Space Station for NASA fired up its powerful first stage engine atop a Florida launch pad in a successful weekend test.

Built by Space Exploration Technologies (SpaceX) of Hawthorne, Calif., the commercial Falcon 9 rocket ignited the cluster of nine engines that make up its first stage for 3.5 seconds during the Saturday test firing, which followed four days of delays due to bad weather and a ground equipment glitch.

SpaceX is planning to launch the new Falcon 9 rocket and a flight qualification version of its gumdrop-shaped Dragon spacecraft sometime between March and May. U.S. Air Force officials have told SPACE.com that April 12 is being considered as a potential launch target, but it is not yet approved.

But regardless of the exact launch date, Saturday?s engine test brings the Falcon 9 rocket a step closer to that test flight, SpaceX officials said.

?The test validated the launch pad propellant and pneumatic systems, as well as the ground and flight control software that controls pad and launch vehicle configurations,? SpaceX officials said in an update. ?The completion of a successful static fire is the latest milestone on the path to the first flight of the Falcon 9, which will carry a Dragon spacecraft qualification unit to orbit.?

Saturday?s successful test marked SpaceX?s second try to test fire the Falcon 9?s first stage atop Space Launch Complex 40 at the Cape Canaveral Air Force Station in Florida.  An attempt four days earlier was aborted when SpaceX?s computer-controlled launch sequence failed to open a valve used to funnel high-pressure helium used to start turbopumps inside the rocket?s first stage engine.

SpaceX?s medium-lift Falcon 9 rocket is a two-stage booster that stands 180 feet (55 meters) tall and is about 12 feet (3.6 meters) wide. The first stage is powered by nine of SpaceX?s own Merlin rocket engines fueled by liquid oxygen and rocket-grade kerosene.

Each Merlin engine generates 125,000 pounds of thrust at sea level. Together the nine engines of Falcon 9?s first stage are designed to generate more 1.1 million pounds of thrust during liftoff.  

For comparison, the Pratt & Whitney RS-68 engine that powers the first stage of a basic United Launch Alliance Delta 4 rocket ? a variant of which launched the new GOES-P weather satellite earlier this month ? generates up to 663,000 pounds of thrust at sea level. The Delta 4 rocket variant that launched GOES-P had two strap-on solid rocket boosters, which increased its liftoff thrust.

Founded by Paypal co-founder Elon Musk, SpaceX has a $1.6-billion contract with NASA to deliver 20 tons of cargo to the space station through 2016. NASA has also contracted another company, the Virginia-based company Orbital Sciences, to provide cargo deliveries using the Taurus 2 rockets and their Cygnus spacecraft that company is building.

The first Falcon 9 flight will not count as one of the three demonstration missions SpaceX has agreed to fly for NASA under the agency?s Commercial Orbital Transportation Services program.

NASA plans to retire its workhorse spaceships ? the three aging U.S. space shuttles ? after the four last flights scheduled for this year. President Barack Obama has canceled NASA?s Constellation program building new spaceships to replace the shuttle fleet, and instead ordered the agency to support the development of commercial spaceships like SpaceX?s Dragon vehicle to launch astronauts into space.

 The next shuttle to blast off will be Discovery, which is due to launch supplies to the space station on April 5. That same shuttle is slated to fly the final shuttle mission in September, to end NASA?s space shuttle era after more than 29 years of flight. The space shuttle Columbia was the first shuttle to launch, on April 12, 1981.

Musk said he and his SpaceX team fully expect to encounter glitches during the Falcon 9 rocket?s shakedown period.

"Problems are expected to occur, as they have throughout the development phase," Musk said in a statement last week.  "The beta phase only ends when a rocket has done at least one, but arguably two or three consecutive flights to orbit."

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