A Coast Guard response boat carrying six crew members crashed into the Stono River bridge during a search for a plane Sunday night, authorities said.
The crash occurred around 10 p.m. and sent all six people aboard the 45-foot vessel to the Medical University of South Carolina with minor injuries, according to a statement from the Coast Guard.
Coast Guard Lt. J.B. Zorn said all crew members were discharged from the hospital early Monday. One person suffered a broken nose, and there were reports of a person who suffered a broken arm, he said. Several people were evaluated for concussions.
The wreck happened during a search for a small plane that fell off radar over James Island. That operation was suspended Monday afternoon with no reports of overdue aircraft.
Zorn said the response boat struck a bridge fender, which damaged the vessel's hull. He didn't know any further details about the crash, which is being investigated by the Coast Guard. A damage estimate was not available.
"I think we're going to find out more, the problem factors, to hopefully avoid it in the future," Zorn said.
Robert Clarkson was sitting in the cabin of his boat docked at the St. Johns Yacht Harbor on Sunday night when he noticed the wake caused by a Charleston Fire Department boat, which he spotted with binoculars.
Clarkson then saw the Coast Guard boat approaching. It's running lights were on, and Clarkson said the bridge's clearance lights were functioning. Weather conditions were clear.
"As the Coast Guard approached, I was concerned because they were clearly left of a proper line up," he said.
Clarkson said the Coast Guard boat reduced power for a few seconds, "like he was trying to figure out which way to go," and then powered back to what appeared and sounded to be "cruising speed" about 100 yards before the bridge. The boat hit a fender and stopped.
"I watched the impact and it was not a glancing blow. It was a direct hit," Clarkson said.
The fire department boat and EMS responded.
The crew members had been looking for the plane that lost signal with the Federal Aviation Administration. Several agencies in a helicopter and boats participated.
Maj. Eric Watson of the Charleston County Sheriff's Office said air support crews searched the area again Monday morning but came up empty. No plane had been reported missing, he said.
"We don't know what happened to the aircraft," Watson said in an email. "There is no evidence of a plane crash."
The search began Sunday after the FAA issued an alert notice for an unidentified aircraft that had approached a runway at the Charleston Executive Airport on Johns Island about 6:15 p.m. but did not land.
The last known radar contact with the plane was near South Grimball Road, according to the Sheriff's Office. The pilot did not communicate on the radio as the plane approached the airport.
"The flight was flying on visual flight rules, so communication with air traffic controllers was not required," a statement from the Federal Aviation Administration said.