NASA: Test Rocket Damage Caused by Parachute Failure
This underwater image shows a large dent in the lower segment of NASA's Ares I-X rocket after it splashed down in the Atlantic Ocean to end a test flight on Oct. 28, 2009.
Credit: United Space Alliance.

This story was updated at 4:50 p.m. ET.

NASA engineers still aren't sure what went wrong with a pair of parachutes that failed during Wednesday's Ares I-X rocket test flight, causing damage to the spent booster when it splashed into the Atlantic Ocean harder than planned.

"There was an indication that we had a parachute problem," said Ares I-X mission manager Bob Ess on Friday. "Afterward, when we saw the parachutes we assumed, properly, that [the rocket] must have hit harder than it should have."

Ares I-X's first stage solid rocket booster was equipped with three giant 150-foot (46-meter) parachutes. One completely failed to deploy, while one appeared to open about half way, Ess said. The result: The booster was falling faster than expected when it hit the sea, so it buckled under the pressure and dented.

Engineers are poring through the copious data returned from the $445 million test launch to discover the root of the issue, but said they're not too worried.

"Damage to the booster is not really a concern to us," Ess said. "We don't plan on reusing it. We got the data and a good test of the parachutes."

In fact, he said, the team that analyzes the parachute data is excited for the opportunity to study the event.

"It makes them kind of happy to go figure out what happened with the parachutes," Ess said. "We want to find these things that aren't quite working the way they're supposed to ? This was just part of doing the test."

The parachutes were designed to deploy after the test flight's first stage separated from its mock second stage. Based on preliminary analysis, it appears that the suspension lines holding the parachutes were at fault, rather than the parachute material itself. The engineers hope to learn more when the first stage is recovered from the ocean over the weekend.

"If it was something to do with the separation event and there was scorching, that gives you some indications," Ess said. "We don't think that's the case," though, he added.

He expects the team will be able to provide a more thorough update next week, but that the event wasn't the kind of emergency that would send engineers into overtime analysis.

"Later next week we'll have a good feeling as to what we think happened," Ess said. "The parachute thing was like 'Hey, look at that.' We're not worried, there's no [major] investigation."

Ares I-X was the first prototype of the Ares I rocket planned to carry astronauts to low-Earth orbit and the moon after the space shuttles retire. Ares I, part of NASA's Constellation program, is currently under review by the White House. The test rocket lifted off from the Kennedy Space Center in Florida on a six-minute fact-finding flight.