Presidente de SAS Pretorio

El SAS President Pretorius fue la última de las tres fragatas tipo 12 de la clase President construidas en el Reino Unido para la Armada Sudafricana (SAN) durante la década de 1960. El buque dedicó la mayor parte de su vida útil a entrenamientos y visitó puertos extranjeros en África y Australia . Fue sometido a una larga modernización durante la década de 1970, y la escasez de personal limitó sus actividades tras su finalización en 1977. El President Pretorius fue dado de baja en 1985 y vendido como chatarra en 1992.

Los buques de la clase President desplazaban 2170 toneladas largas (2200 t) a carga estándar y 2605 toneladas largas (2647 t) a carga profunda . Tenían una eslora total de 370 pies 0 pulgadas (112,78 m) , una manga de 41 pies 0 pulgadas (12,5 m) y un calado profundo medio de 17 pies 6 pulgadas (5,33 m) . ^{[ 1 ] : 238} Los buques estaban propulsados ​​por un par de turbinas de vapor con engranajes English Electric , cada una impulsando un eje de hélice , utilizando vapor suministrado por dos calderas Babcock & Wilcox . Las turbinas desarrollaban un total de 30 000 caballos de fuerza en el eje (22 000 kW) que proporcionaban una velocidad máxima de 30 nudos (56 km/h; 35 mph) . ^{[ 2 ] : 64} Transportaban 309 toneladas largas (314 t) de fueloil que les proporcionaban una autonomía de 4500 millas náuticas (8300 km; 5200 mi) a 12 nudos (22 km/h; 14 mph) . Su tripulación estaba compuesta por 14 oficiales y 200 marineros . ^{[ 1 ] : 238}                   

The Presidents were armed with one twin-gun mount for QF 4.5-inch (114 mm) Mk Vdual-purpose guns forward and one twin mount for 40-millimetre (1.6 in) Boforsanti-aircraft guns. For anti-submarine work, the ships were fitted with Type 162, 170, and 177M sonars for the pair of triple-barrelled Mk 10 Limboanti-submarine mortars. They were equipped with a Type 293Q surface-search radar, Type 262 and 275 gunnery radars, Type 277Qheight-finding radar and a Type 978 navigation radar.^{[1]:220–22,238}

By the mid-1960s, it was obvious that the sonars of the President class were capable of detecting submarines well outside the range of the Limbo anti-submarine mortars and the South Africans decided to follow the lead of the Royal Navy (RN) in giving them the ability to operate helicopters that could carry anti-submarine torpedoes or depth charges to a considerable distance from the ships. Therefore, the forward Limbo mortar was removed and its space was plated over to form a small flight deck. The Bofors mount, its director and the aft superstructure was replaced by a hangar for a Westland Wasp helicopter. Two single Bofors guns were positioned on the hangar roof and provisions were made for four 0.5-inch (12.7 mm) Browning machine guns. A pair of American 12.75-inch (324 mm) Mk 32 triple-barrelled anti-submarine torpedo tubes were added amidships and their electronics were upgraded, including the addition of a Thomson-CSF Jupiter early-warning radar atop a new mainmast and a Selenia Orion fire-control system. In addition, President Pretorius was converted to use diesel fuel and some of her water ballast tanks were converted into fuel tanks.^[1]:227

La Armada Sudafricana encargó tres fragatas de la clase President a finales de la década de 1950 tras el Acuerdo de Simonstown con la Marina Real Británica. La President Pretorius , nombrada en honor al primer presidente de la República Sudafricana , ^{[ 1 ] : 220, 223} fue la última de las tres fragatas gemelas y fue encargada a Yarrow Shipbuilders el 29 de julio de 1959. Su construcción comenzó en su astillero de Scotstoun , Glasgow, el 21 de noviembre de 1960 ^{[ 3 ] : 22} y fue botada el 28 de septiembre de 1962 por la Sra. Mientjie Grobelaar, esposa del general Pieter Grobbelaar , jefe de las Fuerzas de Defensa Sudafricanas . Entró en servicio el 18 de marzo de 1964 bajo el mando del capitán James Johnson , posteriormente jefe de la Armada . ^{[ 1 ] : 223}

President Pretorius was escorted into Cape Town by her two sisters, President Kruger, President Steyn, the destroyerSimon von der Stel and four smaller warships to be greeted by the Chief of Naval Staff, Rear AdmiralHugo Biermann, on 26 September.^[3]:57–58 After 1964, the British government was reluctant to be seen openly cooperating with the apartheid government of South Africa and limited itself to exercises as their ships passed by. In September 1967, the 10th Frigate Flotilla, consisting of President Pretorius, President Kruger, and the newly commissioned replenishment oilerTafelberg, participated in one such exercise with the aircraft carrierEagle, the frigate Loch Fada and the submarine Ambush. The flotilla departed Simon's Town on 7 October 1968 for Australia and arrived in Fremantle on the 23rd. They continued onwards to Sydney and then participated in the Remembrance Day ceremony in Melbourne on 11 November. The ships departed three days later, bound for home, but they were forced to put into Fremantle when a pump in President Pretorius burnt out en route. They finally reached home on 3 December. A year later, a squadron consisting of Simon von der Stel, President Pretorius, Tafelberg and two minesweepers visited Portuguese Angola.^{[3]:117,120–22}President Kruger and President Pretorius trained with a passing British squadron in July–August 1970.^[1]:227

By this time, the navy was experiencing shortages of manpower and the ship was laid up on 1 September to be used as an accommodation ship while President Steyn was finishing up her modernisation.^[3]:89President Pretorius was formally decommissioned on 11 May 1971,^[1]:227 but languished in reserve for some time before actual work began. The ship did not recommission until 12 July 1977 in marked contrast to the time required to modernise her sisters.^[3]:89 She conveyed the remains of the Xhosa Chief Maqoma from Robben Island to Ciskei in August 1978. Almost three years later, in May 1981, President Pretorius and President Kruger participated in the 20th anniversary of the republic's founding and exercised with a squadron from the Republic of China (Taiwan). Shortly afterwards, the two sisters made a showing the flag cruise along the East African coast. After the accidental sinking of President Kruger in 1982 and the earlier laying up of President Steyn, President Pretorius was the last of the sisters remaining active. She was refitted during the early 1980s to lay mines and to operate assault boats. The ship exercised with another Taiwanese squadron in mid-1985 before she was decommissioned on 26 July due to manpower shortages and lack of funds. Plans to reactivate and modernise President Pretorius were made later in the 1980s, but shortages of money prevented them from being realized.^{[1]:233–34,237} The ship was sold for scrap on 9 December 1992 and subsequently broken up.^[3]:206