It's so fast it can out-run a lot of inclement weather, but riding on twin hulls also gives it a different motion than most Navy ships, and in 6- to 8-foot seas yesterday several miles off Bellows, that motion felt like a bobbing cork. Food trays, cups and condiments slid across mess tables. For a time, no at-sea operations were held with the rigid-hull inflatable boats used by Naval Special Clearance Team One for mine counter-measures in RIMPAC.

The big Pacific naval exercise under way off Hawai'i includes at least 15 nations, 40 ships and 18,000 sailors.

The Navy clearly sees a lot of potential for the 320-foot all-aluminum transports, as does the Army and the private sector.

Adm. Tom Fargo, commander of U.S. forces in the Pacific, said in March that he was looking at putting special operations forces and Marines on a high-speed vessel to interdict terrorists operating at sea.

The Army's leased HSV-X1 Joint Venture is at Pearl Harbor unrelated to RIMPAC and will be here through the beginning of August.

Hawai'i Superferry Inc., meanwhile, plans to offer high-speed service between the Hawaiian islands starting in 2006 for passengers and cars.

For RIMPAC, the Swift — which draws only 11 feet of water and can get in close to shore — is being used as a counter-mine platform.

It can just as easily be switched to anti-submarine warfare or troop and vehicle transport.

It's also a test-bed for Navy modularity with the Littoral Combat Ship in development.

"That's the whole idea — they are trying to develop HSV as a multipurpose kind of modular platform," said Cmdr. Jon Lux, mine counter-measures commander for a RIMPAC task force.

The leased Swift, based out of Ingleside, Texas, will be deploying divers and underwater autonomous vehicles — torpedo-shaped robots that look for mines — as part of its mine counter-measure role ahead of a Marine amphibious landing at Bellows on Monday.

Lux said more damage has been done to ships from mines than any other means of anti-surface warfare.

Mines are cheap, and "it only takes one mine in an area to close it down (to shipping)," Lux said yesterday aboard the USS Dubuque, an amphibious transport dock ship out of San Diego, and one of five ships in Task Force 170.

Mines with names like "Manta" and "Rockan" explode on the sea floor, creating an upsurge of air that breaks the keel of ships passing overhead.

In the first Gulf War, the Tripoli and the Princeton were hit by mines.

The exercise under way also includes checking for dummy mines in a shipping lane between Lana'i, Maui and Moloka'i. The Dubuque was about 25 miles south of Lana'i yesterday.

Naval Special Clearance Team One has 24 divers on board the Swift.

Dolphins with the unit, which are not part of this exercise, surveyed the port of Umm Qasr in Iraq during Operation Iraqi Freedom.

Engineman 1st Class David Andrews, 33, who works with underwater sonar, said the Swift is "interesting."

"It's definitely one of the smaller ships I've been on," he said.

"It has a lot of advantages and disadvantages. A disadvantage is it tends to ride a little rougher. On the plus side, with a smaller crew it's a little more personalized."

As part of RIMPAC, four retired Navy ships are being sunk. The Peoria was sunk yesterday morning. The Decatur, Harry Hill and Kinkaid will be sunk this week.