SUNNYVALE, Calif., Sept. 24, 2013 /PRNewswire/ -- The U.S. Navy has conducted four successful test flights of the Trident II D5 Fleet Ballistic Missiles built by Lockheed Martin [NYSE: LMT]. The U.S. Navy launched the unarmed missiles Sept. 10 and 12 in the Atlantic Ocean from a submerged Ohio-class submarine home-ported at Naval Submarine Base Kings Bay, Georgia. This event marked the 145 th, 146 th, 147 th and 148 th successful test flights of the D5 missile since design completion in 1989 – a reliability record unmatched by any other large ballistic missile. "This ultra-capable system serves a critical role in deterring aggression," said Doug White, vice president of Fleet Ballistic Missile programs, Lockheed Martin Space Systems Company, the Navy's Trident missile prime contractor. "We are dedicated to supporting Navy Strategic Systems Programs in assuring the system's continued readiness, reliability, performance and affordability." The Navy launched the missiles as part of Follow-on Commander's Evaluation Tests. The missiles had been converted into test configurations using kits produced by Lockheed Martin that contain range safety devices and flight telemetry instrumentation. As required by the Department of Defense's National Command Authority, the U.S. Navy conducts a continuing series of operational system evaluation tests of the Trident Strategic Weapon System under the testing guidelines of the Joint Chiefs of Staff. First deployed in 1990, the D5 missile is currently aboard U.S. Navy Ohio-class and U.K. Royal Navy Vanguard-class submarines. The three-stage, solid-propellant, inertial-guided ballistic missile can travel a nominal range of 4,000 nautical miles and carries multiple independently targeted reentry bodies. The Fleet Ballistic Missile team has produced six generations, each more capable than its predecessor: the Polaris A1, Polaris A2, Polaris A3, Poseidon C3, Trident I C4 and Trident II D5 missiles.