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.

World War II
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.

Modern usage
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 1400 nmi at 12 kn for five days without refueling.

YPs are 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.

The primary mission of the Training Patrol Craft (YP) is to provide the midshipmen professional training course with practical training afloat on a robust platform to conduct professional development in a safe shipboard environment equipped with systems essential to modern seamanship and navigation. Such training is designed to develop within midshipmen the abilities of an Officer-of the Deck, a proficiency in navigation, and a working knowledge of afloat operations.

General Characteristics, YP 654 class (YP 663)

 * Primary Function: Training.
 * Builder: Stephens Bros., Inc. (YP 665: Elizabeth City Systems).
 * Propulsion: four 6-71N Detroit diesel engines 165 shaft horsepower each @ 1800 rpm, 2 propellers.
 * Length: Overall: 81 ft, 24 meters; Waterline Length: 77 ft, 23.47 meters.
 * Beam: 18 ft, 5.5 meters.
 * Displacement: 66 tons full load, 67 metric tons; Dead Weight: 11 tons, 11.5 metric tons.
 * Draft: 6 ft, 1.8 meters.
 * Speed: 12 kn, 19.6 km/h.
 * Range: 1800 nm, 3300 km.
 * Hull Material: Wood hull, aluminum superstructure.
 * Crew: Officers: 2 Enlisted: 8; Safe capacity: 50 people.

General Characteristics, YP 676 and YP 696 classes

 * Primary Function: Training.
 * Builder: Peterson Builders (YP 676 through 682) and Marinette Marine (YP 683 through 700). Differences between the YP 676 class and the YP 696 class are only minor configuration changes.
 * Propulsion: 12V-71N Detroit diesel engines, 2 propellers, horsepower rating 437 shaft horsepower @ 2,100 rpm.
 * Length: Overall: 108 feet (32.9 m); Waterline Length: 102 feet (31.1 m).
 * Beam: 24 feet (7.3 m).
 * Draft: 8 feet (2.5 m).
 * Speed: 12 knots (19.6 km/h).
 * Range: 1800 nautical miles (3300 km).
 * Hull Material: Wood hull, aluminum superstructure.
 * Crew: Officers: 2 Enlisted: 4; Safe Capacity: 50 people.
 * Ships:
 * (T/V Liberator (YP 679)), United States Merchant Marine Academy, Kings Point, NY (USMMA)
 * (YP 680-692), United States Naval Academy, Annapolis, MD (USNA)
 * (YP 694), United States Naval Academy, Annapolis, MD (USNA)
 * (YP 695), United States Naval Academy, Annapolis, MD (USNA)
 * (YP 696), United States Naval Academy, Annapolis, MD (USNA)
 * (YP 697), Naval Undersea Warfare Center Division, Keyport, WA
 * (YP 698), United States Naval Academy, Annapolis, MD (USNA)
 * (YP 700), United States Naval Academy, Annapolis, MD (USNA)
 * (YP 701), Naval Undersea Warfare Center Division, Keyport, WA
 * (YP 702), United States Naval Academy, Annapolis, MD (USNA)

General Characteristics, YP 703 class (under construction)

 * Primary Function: Training
 * Builder: C&G Boat Works Inc. (YP 703 through YP 708)
 * Propulsion: 2x600 bhp (2x448kW) Cat C-18 diesel engines @ 1,800 rpm, 2 fixed pitch propellers.
 * Length: Overall: 116 feet (35.5 m); Waterline Length: 109 feet (33.2 m).
 * Beam: 27.9 feet (8.51 m).
 * Displacement: 227.6 Metric Tonnes (223.9 long tons)
 * Draft: 7.87 feet (2.40 m).
 * Speed: 12.6 knots (23.3 kilometers per hour).
 * Range: 1,882 nautical miles (3,485.5 kilometers).
 * Hull Material: Welded steel, mono-hull construction.
 * Crew: Officers: 4 Crew: 6 Midshipmen: 30.
 * Ships:
 * (YP 703-704), United States Naval Academy, Annapolis, MD (USNA)