Yard patrol boat

Yard Patrol craft are used by the United States Navy for training and for research purposes. They are designated as YP in the Hull classification symbol system.

Following the attack on Pearl Harbor the United States Navy leased California based tuna boats for the duration of the war or "until victory". On February 16, 1942, San Diego Port Director Commander W.J. Morcott called a meeting of tuna skippers and crews at the Naval Armory Reserve telling the men “The Navy needs men to man the [clippers] — experienced men, like yourselves. Needless to say, duty in the war zones will be hazardous.” Six hundred tuna boat men volunteered to join their boats in the navy. The boats were painted navy grey and had their names replaced with numerical designations. The ships patrolled the coasts of the United States, the Panama Canal and served in several battles of the South Pacific, particularly the Battle of Guadalcanal.

The YPs are used to teach familiarization with water craft, Basic Damage Control and underway instruction of Basic to Advanced Seamanship and Navigation. Yard Patrol craft provide realistic, at-sea training in navigation and seamanship for midshipmen at the U.S. Naval Academy in Annapolis, Maryland, and candidates at Officer Candidate School, Newport, Rhode Island. These craft can cruise for 1,400 nautical miles (2,600 km) at 12 knots (22 km/h) for five days without refueling.

YP701 is used at the Naval Undersea Warfare Center Division in Keyport, Washington, to measure mobile underwater target and torpedo radiated noise plus ambient water noise conditions; serve as a platform for deployment of suspended, stationary, in-water acoustic targets during on-range torpedo proof and test operations; deployment of countermeasure emulator during torpedo operations; and deployment of oceanographic measurement instrumentation to determine seawater conductivity and temperature at the depth(s) of interest.

The new Training Patrol Craft (YP) are designated the YP 703 class. The general craft characteristics of the YP 703 class emphasize habitability, training areas, hull structure, integrated bridge, maneuverability, propulsion plant configuration, and, for training purposes only, simulated Underway Replenishment. The main and auxiliary systems and electronics are state-of-the art, Commercial-Off-The-Shelf equipment. Design, construction, and selection of systems, sub-systems, and equipment along with associated software are consistent with reduced Total Ownership Cost and shall facilitate system maintenance and periodic upgrades.

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