Kaivan-class patrol craft

The Kaivan (Persian: کیوان) is a class of large patrol craft operated by the Islamic Republic of Iran Navy. The ships in this class are modified versions of the American Cape-class vessels, built by the United States Coast Guard Yard in the 1950s.

Class overview
Builders	USCG, Curtis Bay
Operators	Islamic Republic of Iran Navy
In service	1956–present
Completed	4
Active	3
Lost	1
General characteristics
Type	Large patrol craft
Displacement	98/100 tons standard 148/150 tons full load
Length	28.9 m (94 ft 10 in)
Beam	6.2 m (20 ft 4 in)
Draught	1.8–2 m (5.9–6.6 ft)
Installed power	Diesel
Propulsion	2 or 4 × NYHMS-1200 engines, 2,120 horsepower (1.58 MW) 2 × shafts
Speed	15–21 kn (28–39 km/h)
Range	2,324 nmi (4,304 km) at 8 knots (15 km/h) 1,500 nmi (2,800 km) at 15 knots (28 km/h)
Complement	15

Design

Sources cite displacement of Kaivan class vessels slightly different. According to Jane's Fighting Ships, the ships have a standard displacement of 100 tonnes (98 long tons) and 150 t (150 long tons) at full load.^[1] Conway's All the World's Fighting Ships puts the numbers at 98 tonnes (96 long tons) and 148 tonnes (146 long tons) for standard and full load displacements respectively.^[2] Combat Fleets of the World mentions only 85 tonnes (84 long tons).^[3] The class design is 28.9 m (95 ft) long, would have a beam of 6.2 m (20 ft) and a draft of 2 m (6 ft 7 in).^[1][2] The length is also recorded 29 m (95 ft).^[3]

Ships in the class

The ships in the class are:^[1][2]

Ship	Pennant number	Commissioned	Status
IRIS Kaivan	201 (ex-61)	14 January 1956	In active service
IRIS Tiran	202 (ex-62)	1957	In active service
IRIS Mehran	203 (ex-63)	1959	Sunk in 1980 or 1981
IRIS Mahan	204 (ex-64)	1959	In active service