SSA drills in Fairhaven aboard MV Nantucket

Evacuation system is tested for ferry.

The Nantucket did not run on its early morning trips on Thursday due to a sewage issue. - Rich Saltzberg

The Steamship Authority held a major evacuation drill aboard the MV Nantucket Monday morning in Fairhaven.

The exercise featured a marine evacuation system, or MES, comprised of a rapidly inflated slide and a 128-person open raft. A second 128-person raft was later deployed in the drill.

Charles Monteiro, SSA assistant port captain, oversaw the drill while Vlad Prato, North American manager for Liferaft Systems Australia, manufacturer of the MES used in the drill, instructed SSA personnel from the deck of the ferry and from within a life raft.

The SSA conducts one such drill each year, according to SSA spokesman Sean Driscoll, though not necessarily on the same vessel, and all MES equipment aboard SSA ferries is inspected yearly. The triangular slide and accompanying raft were launched Monday from the 01 deck, the deck just above the freight deck. SSA personnel and some visiting Massachusetts Maritime Academy cadets then luged through the tunnel-like slide into the raft. The doors to the MES, which are set in the broadside of the hull, were craned away ahead of time for the drill. In an emergency, however, they are jettisoned.

“We lose the doors,” Monteiro said. “The doors are sacrificial.”

The Nantucket has a complement of six rafts, each with 128-person capacity, Driscoll told The Times. The maximum passenger capacity is 752. Along with 16 crew, the life raft capacity and the maximum number of people aboard are both 768. The same type and brand of evacuation system is installed on the MV Eagle, MV Island Home, and MV Martha’s Vineyard, according to Driscoll.

A motor lifeboat from Station Menemsha monitored the drill alongside another Coast Guard boat. Tisbury harbormaster John Crocker came across with the motor lifeboat crew to observe the exercise.

The MES aboard the Nantucket is a coastal system, as opposed to an ocean system, which employs a canopy over the raft and is equipped with additional features, Prato said. The Nantucket’s MES is rated for force 6 wind on the Beaufort Scale, he said. Force 6 wind is considered a “strong breeze,” according to a NOAA Beaufort Scale website. Such wind makes waves of 8 to 13 feet, the site states.

The SSA has never had to use the system in an emergency onboard any of its ferries, Driscoll said.