A U.S. Navy submarine floating beneath the surface of the Pacific Ocean fired an unarmed Trident D5 strategic missile, marking the 135th consecutive successful test flight of the Lockheed Martin-built weapon since 1989.

The Navy launched the missile as part of an operation to certify that the USS Nevada, recently returned to sea following a shipyard overhaul period, is ready for deployment.

The missile was converted into a test configuration using a test missile kit produced by Sunnyvale, Calif.-based Lockheed Martin Space Systems. The kit includes range safety devices and flight telemetry instrumentation.

โ€œThis test demonstrates the readiness and reliability not only of the missile, but also elements of the Trident II D5 Strategic Weapon System,โ€ Melanie A. Sloane, Lockheed Martin vice president of Fleet Ballistic Missile programs, said in a statement.