John F. Sullivan Jr., chairman and chief executive officer of Bath Iron Works, Bath, Maine, announced the appointment of James M. Blenkhorn Jr. as vice president of marketing.

Mr. Blenkhorn is rejoining Bath Iron Works after leaving in February 1979 to serve first as group vice president of Sun Shipbuilding Corporation, Chester, Pa., and then as president of Equitable Shipyards, Inc., New Orleans, La.

He originally joined BIW in August 1969 as ship superintendent for construction of three West German destroyers. He then held a series of executive positions, concluding as manager of commercial new construction and Navy overhaul.

A graduate of the Maine Maritime Academy and the Naval Post Graduate School, he sailed as a licensed engineer in the U.S. merchant marine. He then served ten years in the U.S. Navy as an engineering officer in destroyers and cruisers, and on command staffs. He currently is a captain in the U.S. Navy Reserve.