By Samantha L. Quigley
American Forces Press Service
April 29, 2009 - When future astronauts prepare to go to the moon or to a rendezvous with the International Space Station, their craft will look suspiciously familiar. Appearing to be a larger version of the Apollo spacecraft's crew module, the new Orion spacecraft is historical in its conical design.
"We know a lot about the aerodynamic properties of this shape," said Alan Rhodes, NASA's Constellation Program test and verification officer. "It's a great, great craft for space.
"It's not a great boat," he deadpanned.
Because the new spacecraft replaces the space shuttle, which has landed on runways, the Constellation Project team needs to be able to tell today's astronauts what to expect when they splash down in the ocean after a mission. The team also needs to develop best practices for getting the astronauts out of the capsule and recovering the vehicle after splashdown.
Toward those goals, the Orion crew module was brought to the calm waters of the test pond at the Naval Surface Warfare Center's Carderock Division in Bethesda, Md., in late March.
No people have been aboard the capsule for any of the testing there, however. That will come later. Preliminary tests results have been gained through observation and instrumentation.
"The key here is safety," Rhodes said. "It's kind of ... 'learn as quick as possible,' but we've got to make sure we're safe, because we don't want anybody getting hurt with this."
Developing best practices for deploying the module's floatation collar is much safer in the pond's calm waters than in 10-foot seas, Rhodes explained.
The procedure began by lowering the 18,000-pound module into the water while team members guided it toward the center with ropes. Once it was in position, two teams of Air Force pararescuemen in rigid, inflatable Zodiac boats attached a sea anchor before deploying and inflating an 18-inch floatation collar. The sea anchor is the first step to slowing the motion of the capsule, which helps to make the crew more comfortable, officials explained.
Once inflated and attached to the module, the blue-and-yellow collar stabilizes the craft further and provides the recovery crew a platform from which to help the astronauts out of the vehicle.
"The Air Force guys are able to use this test pool to test out all the procedures they're going to want to use when we go to the ocean," Rhodes said.
They also got to test out a procedure they hope they won't have to use when the main hatch on the side of the module failed to open properly during the tests. This glitch, which later was easily explained, had the recovery crew looking to the alternate hatch on top of the vehicle.
"On top, ... there's a secondary hatch called the docking hatch," Rhodes said. "That'll be the hatch they use to enter the space station [or] to attach themselves to the lunar lander [or] the Martian vehicles. It also is a secondary egress path."
The team also should be able to tell the astronauts what to expect in different sea states, he said.
"It helps us understand, 'We think you will have this probability of being sick due to the motions.' 'We think you'll be able to move based on our interpretation of these motions in these manners,'" Rhodes explained.
When all the testing on the Orion crew module is complete the Constellation Project team will have developed best practices for retrieving the crew and recovering the capsule in just about any sea state, Rhodes said.
"It's extremely important to us to make sure that they can [recover the vehicle and crew] in 10-, 12-, and 14-foot seas," said Don Pearson, project manager for the post-landing test. "The reason for that is we want to have what's called a very high launch probability. Any day of the year I want to be able to launch my spacecraft from Kennedy [Space Center]. We have to be able to say, 'Yeah, we've got really rough weather off Boston, but not a problem. We could still pick you guys up [if the capsule splashed down there]. Let's go. Let's launch today.'"
While the capsule has a retro look, sentiment was not what led NASA to resume water landings upon re-entry; it was practicality. While the Russian space program has the expansive, soft soils of Kazakhstan on which to land their Soyuz spacecraft, the United States is not so fortunate.
"Weight is the biggest issue, and a system that can keep the astronauts safe landing on land," said Navy Cmdr. Andy Quiett, the Defense Department's liaison to NASA for the Constellation Program. "We don't have quite that big a [piece of] real estate in the U.S.
"There are several landing sites that they've evaluated," he continued, "and NASA made the call that weight costs money to put [the capsule] into orbit and to have a system to protect the capsule for a land landing. I know the astronaut office wants the safest landing they can have, and the water landing provides that."
The last splashdown of a crew module was Apollo 17, Quiett said. That was Dec. 19, 1972.
The team's consensus during a post-test debrief was that all had gone well and they were on the right track. That didn't mean they were done, however. The group took a break before returning to the pond to run through the same exercise at night.
Wednesday, April 29, 2009
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