Ship decommissioning

Ship commissioning is the act or ceremony of placing a ship in active service, and may be regarded as a particular application of the general concepts and practices of project commissioning. The term is most commonly applied to the placing of a warship in active duty with its country's military forces. The ceremonies involved are often rooted in centuries old naval tradition.

Ship naming and launching endow a ship hull with her identity, but many milestones remain before she is completed and considered ready to be designated a commissioned ship. The engineering plant, weapon and electronic systems, galley, and multitudinous other equipment required to transform the new hull into an operating and habitable warship are installed and tested. The prospective commanding officer, ship's officers, the petty officers, and seamen who will form the crew report for training and intensive familiarization with their new ship.

Prior to commissioning, the new ship undergoes sea trials to identify any deficiencies needing correction. The preparation and readiness time between christening-launching and commissioning may be as much as three years for a nuclear powered aircraft carrier to as brief as twenty days for a World War II landing ship. USS Monitor, of American Civil War fame, was commissioned less than three weeks after launch.

Regardless of the type of ship in question, a vessel's journey towards commissioning in its nation's navy begins with process known as sea trials. Sea trials usually take place some years after a vessel was laid down, and mark the interim step between the completion of a ship's construction and its official acceptance for service with its nation's navy.

Sea trials begin when the ship in question is floated out of its dry dock (or more rarely, moved by a vehicle to the sea from its construction hangar, as was the case with the submarine USS Virginia), at which time the initial crew for a ship (usually a skeleton crew composed of yard workers and naval personnel) will assume command of the vessel in question. The ship is then sailed in littoral waters for the purpose of testing the design, equipment, and other ship specific systems to ensure that they work properly and can handle the equipment that they will be using in the coming years. Tests done during this phase can include launching missiles from missile magazines, firing the ship's gun (if it has one), conducting basic flight tests with rotary and fixed-wing aircraft that will be assigned to the ship in the future, and various tests of the electronic and propulsion equipment. Often during this phase of testing problems arise relating to the state of the equipment on the ship in question, which can result in the ship returning to the builder's shipyard to address the concerns in question.

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