By Todd Halvorson, Florida Today
CAPE CANAVERAL, Fla. - The SpaceX Dragon capsule, which was launched Friday morning, has developed a problem on its way to the International Space Station.
The trouble cropped up nine minutes after liftoff, the Associated Press reported.
SpaceX's billionaire founder Elon Musk reported via Twitter that there's a problem with the thrusters on the spacecraft:
"Issue with Dragon thruster pods. System inhibiting three of four from initializing. About to command inhibit override."
Musk is monitoring the flight from SpaceX Mission Control in California.
More than 1 ton of space station supplies is aboard the Dragon. It's supposed to arrive at the space station Saturday morning.
The launch, capping a five-month turnaround from a successful mission , was a dramatic demonstration of the vehicle's ability to survive an engine failure in flight.
Standing 157 feet tall, the powerful Falcon 9 blasted off from Cape Canaveral Air Force Station at 10:10 a.m. EST with a Dragon space freighter. It's the company's second cargo-delivery mission to the International Space Station.
Musk is well known for proclaiming that the Falcon 9 is the first rocket designed with "engine-out" capability since NASA's Saturn V moon rocket.
Many at heritage aerospace industry companies scoffed. Nine Merlin 1C engines are linked together in a square at the base of the Falcon 9's first stage. Surely, an engine failure would result in collateral damage, leading to a catastrophic loss of mission.
But one-minute and 19 seconds into a brilliant night launch last October, a defect in a Nomex-and-Kevlar flak jacket around one of the rocket's engines triggered a depressurization within its combustion chamber.
The rocket's prime flight computer detected the problem and commanded an engine shutdown. The engine's protective fairing broke apart. Pieces of it were violently consumed in the fire-orange stream that trailed the rocket.
It looked as if the engine had exploded. But it didn't. It was shut down automatically, as intended under the circumstances. Nonetheless, the Falcon 9 delivered the Dragon spacecraft to orbit and it arrived at the International Space Station 30 minutes ahead of schedule. The first of 12 SpaceX cargo delivery missions under a NASA contract valued at $1.6 billion ended up a success.
"As a matter of fact, I have to tell you that I think the industry and the public was dramatically impressed by the fact that we had an engine issue, an engine shutdown, and still made mission," SpaceX president Gwynne Shotwell said Thursday.
"I want to point out that this vehicle has been designed to accommodate an engine out, and though you never necessarily want to see it happen, it's nice that we've demonstrated the vehicle (operates) as it was designed."
Over the past four months and 22 days, SpaceX engineers have been busy with an investigation into the engine failure - one focused on finding the root cause, fixing the problem, and flying again.
That's considered fairly fast in the U.S. aerospace industry.
"We did extensive analysis, obviously, to understand the problem, extensive assessment and testing on these particular engines," Shotwell said.
Investigations into engine failures typically involve what aerospace engineers call "Non-Destructive Testing." For example, ultrasonic examinations, radiography or thermography might be used to detect flaws on Nomex or Kevlar without destroying the material being tested.
NASA International Space Station Program Manager Mike Suffredini said the agency lent SpaceX a hand during its investigation into the October 2012 engine failure. But the company still is clearly looking for help in this discipline.
"It's as much an art as a science, and we certainly are getting much better at it as we mature here," Shotwell said. "But I am going to make a shameless call for any extraordinary NDE experts that want to come and change the state of science, or the state of the art, we're hiring you at SpaceX."
USA Today/Florida Today