The first launch of SpaceX's upgraded Falcon 9 rocket in September will count as one of the three successful flights to certify the launcher to carry the U.S. military's most valuable payloads into orbit, despite a glitch with the rocket's upper stage engine during a demonstration maneuver after deployment of a Canadian research payload, the Air Force announced last week.

Photo of the Falcon 9 rocket's Sept. 29, 2013, launch from Vandenberg Air Force Base, Calif. Photo credit: SpaceX
 
The Air Force's decision moves SpaceX closer to competing to launch the military's most expensive and vital communications, missile warning, navigation and intelligence satellites.

SpaceX would join incumbent contractor United Launch Alliance, which operates the Atlas 5 and Delta 4 rockets for the Air Force's Evolved Expendable Launch Vehicle program.

The Air Force is seeking reduced-cost launch options in the wake of rising prices for launch services in recent years. Officials have targeted some of the blame for spiraling costs on the retirement of the space shuttle and the cancellation of NASA's Constellation moon program, now replaced with the heavy-lift Space Launch System and Orion crew capsule in development for human missions beyond low Earth orbit.

The Sept. 29 launch of the Falcon 9 v1.1 rocket was the debut flight of SpaceX's new-generation satellite launcher, featuring more powerful Merlin 1D engines, a simplified stage separation system with three connecting points instead of 12, a triple-redundant flight computer, and new software.

The maiden flight of the Falcon 9 v1.1 delivered Canada's Cassiope satellite into a polar orbit to conduct space weather research and communications relay experiments.

SpaceX considered the Sept. 29 launch a test flight, and engineers tried to relight the Falcon 9's upper stage Merlin 1D engine after releasing Cassiope into orbit.

But the rocket's on-board computer aborted the engine restart.

SpaceX officials said engineers traced the problem to lines feeding igniter fluid into the engine's thrust chamber. Between the engine burns, the lines froze from exposure to cryogenic liquid oxygen, which the Merlin engine consumes along with kerosene fuel stored at warm temperatures.

The Air Force Space Command's Space and Missile Systems Center is still assessing two subsequent Falcon 9 launches Dec. 3 and Jan. 6, but those missions successfully put their commercial telecom payloads into orbit without any problems.

The Falcon 9 rocket's upper stage Merlin 1D engine as seen from an on-board video camera. Photo credit: SpaceX
 
SpaceX and the Air Force signed a Cooperative Research and Development Agreement in June 2013, setting conditions before the Air Force permits the company to compete for launch contracts for the military's most critical satellites.

"This flight represents one of many certification requirements jointly agreed to between the Air Force and SpaceX," said Lt. Gen. Ellen Pawlikowski, SMC commander at Los Angeles Air Force Base, Calif.

The agreement calls for three successful flights of a common launch vehicle configuration, technical reviews, audits and independent verification, and validation of the launch vehicle's ground systems and manufacturing processes, according to the Air Force.

"Where possible, the Air Force will work jointly with SpaceX to accelerate completing the requirements from these phases to expedite certification," the Air Force said in a statement.

SpaceX currently assembles Falcon 9 rockets with their payloads horizontally, then rolls the rocket to the launch pad before erecting it on top of the launch mount. Company officials have said they will adjust their procedures to accommodate the military's requirement to integrate national security payloads in a vertical orientation.

"We plan to accommodate vertical integration at out launch pads for any Air Force mission that requires it, and we'll make the necessary modifications at our own expense," a SpaceX spokesperson said last year.

An Air Force spokesperson said national security spacecraft are currently not designed for horizontal integration.

"The EELV program is required to provide a common interface so spacecraft do not require re-design in order to move to a different EELV launch vehicle," the Air Force spokesperson said. "All current and future EELV launch vehicles are required to comply with this standard interface."

The Hawthorne, Calif.-based space transportation company could offer the Air Force $1 billion in launch cost savings per year, according to SpaceX spokesperson Emily Shanklin.

While ULA and the Air Force signed a sole-source deal for 36 Atlas 5 and Delta 4 rocket cores to guarantee access to space for military payloads, the service identified 14 missions to open up to competition with SpaceX once the Falcon 9 rocket is certified.

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