SpaceX is sorting through a first-stage Falcon 9 engine anomaly that occurred when the two-stage booster lifted off for the International Space Station on Oct. 7 under a $1.6 billion NASA Commercial Resupply Services contract that signals the restoration of U.S. cargo delivery and return capabilities lost with the space shuttle’s 2011 retirement.

Engine No. 1 experienced a sudden pressure loss without an explosion that led to a shutdown command about 79 sec. into the nearly 10-min. ascent to orbit, according to an Oct. 8 statement from Katherine Nelson, the Hawthorne, Calif., based company’s vice president for marketing and communications.

The Dragon capsule — carrying a nearly 1,000-lb. multinational cargo of food, clothing and research gear — reached its initial target orbit despite the engine failure, via an extended propulsion system burn. The capsule was on course to reach the orbiting science laboratory early Oct. 10, as scheduled.

“Initial data suggests that one of the rocket’s nine Merlin engines, Engine 1, lost pressure suddenly and an engine shutdown command was issued immediately. We know the engine did not explode, because we continued to receive data from it,” according to the SpaceX statement. “Our review indicates that the fairing that protects the engine from aerodynamic loads ruptured due to the engine pressure release, and that none of Falcon 9’s other eight engines were impacted by this event.”

The incident occurred as the spacecraft was achieving supersonic velocity and rising through Max Q, the point of maximum dynamic pressure, according to the mission timeline.

The Falcon 9 performed as designed to achieve orbit with an engine loss, said SpaceX President Gwynne Shotwell, who first addressed the incident in a post-launch news briefing with NASA Administrator Charles Bolden.

“We will continue to review all flight data in order to understand the cause of the anomaly, and will devote the resources necessary to identify the problem and apply those lessons to future flights,” according to the follow-up SpaceX statement.

In spite of the difficulty, Bolden appeared pleased with the CRS-1 mission start and those who question a greater commercial role in NASA operations.

“This was a critical event for NASA and the nation tonight,” the administrator said moments after the Falcon 9/Dragon lifted off from Cape Canaveral on Oct. 7 at 8:35 p.m., EDT. “Just a year after the retirement of the space shuttle, we have returned space station resupply missions to U.S. soil.”

The SpaceX CRS-1 flight and those expected to begin in 2013 with a second ISS resupply provider, Orbital Sciences Corp., of Dulles, Va., bode well for efforts by U.S. policy makers to shift NASA’s focus away from Earth-orbit operations to deep-space science initiatives and human exploration, Bolden says.

“What this does is strengthen our position of leadership,” he said of U.S. global standing in space. “Every time we have a successful mission, that gives the nonbelievers one more opportunity to get on board.”

Aboard the ISS, NASA and Japanese astronauts Sunita Williams and Akihiko Hoshide will be positioned in the Cupola observation deck at the controls of Canada’s robot arm as Dragon makes its Oct. 10 approach. Once Dragon is within reach of the 58-ft.-long robot arm, the two astronauts will grapple and berth the capsule. The grapple is scheduled for 7:23 a.m. EDT.

As the CRS-1 freighter is off-loaded, the spacecraft will be reloaded with more than 1,200 lb. of frozen biomedical specimens, research gear and equipment headed back to Earth.

Current scheduling calls for Dragon to depart the orbiting science lab on Oct. 28, followed by a same-day parachute descent into the Pacific Ocean about 250 mi. off the Southern California coast. SpaceX recovery ships will be standing by.

Each of the Dragon mission milestones was successfully demonstrated in May during NASA’s Commercial Orbital Transportation Systems program flight.