SAN PEDRO, California NASA's next spaceship, the Orion capsule, has had a wet summer.

For a full week in August, NASA engineers and the U.S. Navy worked side by side to practice retrieving the new spacecraft from the Pacific Ocean after a water splashdown like the one that will end the capsule's upcoming test flight in December.

The tests were based from the USS Anchorage, an amphibious Navy transport that was temporarily assigned to NASA's Orion recovery exercises. Another round of sea trials is scheduled for September. [NASA's Orion Spaceship in Pictures]

"We ran six or seven different tests," said Mike Folger, who manages part of the Orion recovery operation from NASA's Kennedy Space Center, as the sea trials ended on Aug. 6. "First, we released it inside the well deck and make sure that we can control it the way we think we can."

The well deck is an area in the rear of the ship that opens to the sea, allowing water to flood inside. Normally, Marines use it to launch amphibious assault craft. For this first in a series of tests, the NASA and Navy teams simply allowed the capsule to wallow inside the back end of the Anchorage.

"Once we got comfortable with that, we released the test article behind the ship and sent a couple of Navy boats out with divers and a horse collar," Folger said. The horse collar loops around Orion, securing the craft to a winched cable that is used to tow Orion into the recovery ship.

Despite a few small hiccups, including one horse collar that began to come unstitched, the tests were successful.

"We did this in calm seas," Folger said. "Then we looked for seas that were a bit more riled up. We're not sure what the weather is going to be like in December in the Pacific, so we need to try it in a number of different conditions."

The first test flight of Orion is called Exploration Flight Test 1 (EFT-1), and will be launched on a Delta 4 Heavy rocket in early December. [How NASA's First Orion Flight Will Work (Video)]

While Orion is a 21st-century spacecraft, its capsule may remind people of the smaller Apollo command modules from the 1960s. And indeed, much learning from that program has contributed to this vessel's testing.

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NASA's New Orion Spaceship Makes a Splash in Ocean Tests