"It was really embarrassing," said Cmdr. Paul Potter, the Coast Guard's new liaison officer with the U. S. Senate, of his first attempt to familiarize congressional and White House staffers with functions of his service. "And so what happens? I take them out and the Coast Guard shoots itself in the foot."

Potter arranged an introductory cruise last week from Baltimore for congressional passengers aboard the Coast Guard Cutter Gallatin. The ship cast off from the Curtis Bay Coast Guard station, traveled 361 yards and went aground, breaking its propellers and blocking traffic on a drawbridge above it.

Potter loaded his guests -- including aides from the White House Defense Office, the Senate's Republican Steering Committee and an aide to Sen. Jesse Helms (R-N.C.) -- onto a nearby boat and ferried them back to the dock. Meanwhile, two tugboats spent more than an hour pushing the 378-foot vessel out of the mud. Motorists trapped in traffic by the raised drawbridge hung over the bridge, heckling the ship's crew and passengers.

Chief Petty Officer John M. Hollins, a Coast Guard spokesman, said the ship was returned to Curtis Bay, where divers immediately began assessing the damage.

The ship had just undergone three months of maintenance and engine work. Capt. James Coen took command 10 days before the grounding. He declined to discuss details of the incident.

Instead of the planned one-day cruise to Yorktown, Va., Potter treated his guests to a tour of the shipyard and a $2 brunch at the base.

"We wanted them to see what a Coast Guard ship is like," Potter said. "They got to see a little more . . . . "