USS Helena SSN-725 FLT II Black Hull Model. Dive with the USS Helena again in this handcrafted 20-inch submarine. Each piece is carved from wood and handpainted to provide a piece you’ll love. Length – 20 inches. US Veteran Owned Business. The product is not intended to be used by children 12 years and younger. The contract to build her was awarded to the Electric Boat Division of General Dynamics Corporation in Groton, Connecticut on 19 April 1982 and her keel was laid down on 28 March 1985. She was launched on 28 June 1986 sponsored by Mrs. Jean Busey, and commissioned on 11 July 1987, with Commander Thomas Moore in command.