A caravan-style car drove off the end of the Steamship Authority dock and was trapped underwater with four patients inside. 

That was the premise of a training scenario staged Sunday morning for the Oak Bluffs dive team.

“An elderly person had a medical event and they gunned it down the terminal,” said Oak Bluffs fire department acting chief John Rose, who conducted the dive team’s first car rescue drill.

Equipment at the ready, 10 Oak Bluffs fire department divers deployed to the scene, taking turns attempting to locate the car, open the locked car doors and rescue the mannequins inside. Once surfaced, the divers performed the “rescue swim,” dragging their patient to the boat, before heaving their patient over the back of the Red, White and Blue by the shoulders. The first rescue was performed in less than 10 minutes. Divers were not told which tools to gather in advance, but some had the foresight to bring a spring-loaded punch to break the windows, Mr. Rose said.

Throughout the drill, divers reported back the rescue boat crews and the personnel on shore via radio, informing them of their progress and the rate of depletion of their air tank. But there were still kinks to be worked out with the system, Mr. Rose said, and sometimes divers were difficult to locate except by the collection of bubbles on the water’s surface. 

The divers wore 5 millimeter wetsuits, which offered some protection against the cold November water. Mr. Rose said drills will continue throughout the off-season. Next weekend, West Tisbury rescue divers will have a chance to dive at the car site, before a Goodale’s crane pulls the car out of the water. As the winter approaches, divers will don dry suits instead, which are more difficult to maneuver underwater, Mr. Rose said. These are more buoyant than the wetsuits and require divers to press the air out of the suit in order to stay underwater.

Last Thursday dive team members had stripped the 1970 caravan of environmental hazards, including the transmission and the motor. The car was then pushed off the end of the Steamship pier Friday without revealing its specific location to the divers.