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Glossary of Terms

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Acceptance Trials (AT) is a rigorous test process and material inspection carried out underway by the government (often represented by the U.S. Navy’s Board of Inspection and Survey (INSURV)) to determine that ships constructed in private industrial shipyards are suitable for delivery.

Builders Trials (BT) is a contractor-conducted event to inspect, test and evaluate a ship's performance underway. One important purpose of BT is to assure the builder and the government that the ship is, or will be, ready for Acceptance Trials (AT). BT typically includes a comprehensive test of all ship's equipment and is similar in scope to AT.

Christening is a long-standing naval tradition including a ceremony wherein the ship’s sponsor (usually a woman) breaks a bottle of champagne across the bow and grants the ship its name.

Commissioning is an elaborate ceremony that officially places the ship in service and adds the prefix U.S. Coast Guard Cutter to her name. Prior to commissioning, it is inappropriate to use the U.S. Coast Guard Cutter title before the ship’s name as the vessel is not yet officially in government service. Although commissioning places the ship in service, much work usually remains to be done by the crew to bring the ship to its full operational capability.

Delivery is the date when all systems have been tested and discrepancies corrected to the government's satisfaction, and a representative from the Coast Guard officially accepts custody of the ship from the shipbuilder. The ship’s pre-commissioning crew moves aboard to perform training, qualification and certification of equipment activities.

Dock Trials is a broad term referring to events conducted at the shipyard to determine the ability of the ship, from a material standpoint, to conduct sea trials safely.

Laying the Keel represents the beginning of a ship's construction. The keel is the key structural member stretching the length of the ship.

Launch is the date when a ship is first placed in the water; the ship must be watertight, but construction need not be complete for launch to take place.

Light-Off occurs as various major components of the ship are completed, energized and tested. Light-off events include electronic systems light-off (which may include the ship’s Command, Control Communications, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) equipment), electrical generator light-off, combat systems light-off, and main engine light-off. These events are significant steps in the construction process.

Machinery Trials (MT) (often synonymous with, or occurring as part of dock trials) are inspections, tests and evaluations specific to the ship's machinery, including its main propulsion system.

Pre-Commissioning (PRECOM) Crews are designated to take charge of the ship following delivery. The PRECOM crew's task is to prepare the vessel and its mission systems for full operational capability in Coast Guard service.

Post-Shakedown Availability is an industrial activity availability following delivery and is used to correct deficiencies found during the shakedown period, or to accomplish other authorized improvements to the ship.

Sail Away is the date of the ship's final departure from the construction yard for its homeport or commissioning site. This date signifies the end of the new construction and the beginning of final preparations for operational service.

Sea Trials is a general term referring to are a series of rigorous, underway tests to determine that the ship's hull, mechanical & electrical and other systems function as required. Trials typically have three phases: dock trials (also machinery trials, conducted while the ship is still tied to the pier), builders trials (done at sea by the contractors who built the ship), and acceptance trials (conducted at sea and ashore by government personnel). Discrepancies noted during trials must be corrected prior to delivery.

Ship Naming traditionally occurs before the ship is christened, while construction is in progress. During the naming phase the ship's sponsor (who will christen the ship) also is selected. In the case of ships named for individuals, an effort is made to identify the eldest living direct female descendant of that individual to perform the role of ship's sponsor.

Stepping the Mast is an ancient practice where coins are placed under or near the ship’s mast. Traditionally, the value of the coins usually adds up to the ship’s hull number.

Last Modified 2/2/2016