Trident Contract Awarded: Lockheed Missiles & Space Co., a division of Calabasas-based Lockheed Corp., has received a $921.6-million defense contract for submarine missiles, the Navy said. The money is to build new Trident II long-range nuclear missiles for America’s strategic Trident submarines. The missile is also known as the D-5. Work on the contract is expected to be completed in September of 1991, the Navy said. Lockheed is one of the nation’s largest defense contractors. The company last year had $3.53 billion worth of business in prime contracts with the Defense Department as its eighth-largest contractor.