Van Speijk class frigate
Encyclopedia
The Van Speijk class frigate were built for the Royal Netherlands Navy
in the 1960s. They were versions of the British Leander class frigate
s with Dutch radars. The British design was chosen in order to enable rapid construction in order to replace elderly destroyer escorts. The ships were modernised in the late 1970s. All six ships were sold to the Indonesian Navy
in 1986-89 and are still in service (as of 2010) as the Ahmad Yani class frigates.
, the DA-02 medium-range air/surface search radar and the M45 combined radar and optical fire control system for the 4.5 in (11.4 cm) guns. The Dutch HSA M44 radar/visual director for the Seacat
anti-aircraft
missiles could automatically target in elevation and bearing and allowed the single Seacat launcher on the British ships to be increased to two launchers on the Dutch ships, each with their own director.
gun and two quadruple mounts for Harpoon
anti-ship missiles were fitted abaft of the funnel. The Mk 10 Limbo
ASW mortar was replaced by a pair of triple Mk 32 torpedo launchers
, one mount on each side of the hangar, and its mount plated over so the flight deck could be increased to allow the ship to carry the larger Westland Lynx
helicopter in lieu of the Wasp carried earlier. The removal of the variable-depth sonar from the quarterdeck to the interior of the stern also allowed more room for the flight deck.
The electronics were also upgraded, the LW-02 radar was exchanged for a LW-03 and the DA-02 was replaced by a DA-05 radar. Most importantly an automated combat management system, SEWACO V, was fitted to aid the ship's captain in decision making. Its power plant was also extensively automated. All told these changes allowed the crew to decrease in size from 254 to about 175 which allowed greatly increased standards of habitability.
launchers. Recently, the two quadruple Harpoon launchers were also replaced by Yakhont missile (SS-N-26) launchers purchased from Russia, because the early version Harpoon missiles previously installed were nearing their obsolescence period. There are also some conflicting reports that the Harpoon missiles were replaced with Chinese-sourced C-802 rather than Russian Yakhont. There are some pictures circulating on the internet showing several vessels of the class carrying box launchers that look much too small to be Yakhont's launchers, but they are the right size for C-802.
Pictures released in March 2011 show that modifications were made to KRI Oswald Siahaan with 4 SS-26 Yakhont VLS cells located in the quarterdeck beside the helicopter hangar.
engines replaced with diesel propulsion.
Royal Netherlands Navy
The Koninklijke Marine is the navy of the Netherlands. In the mid-17th century the Dutch Navy was the most powerful navy in the world and it played an active role in the wars of the Dutch Republic and later those of the Batavian Republic and the Kingdom of the Netherlands...
in the 1960s. They were versions of the British Leander class frigate
Leander class frigate
The Leander class, or Type 12I frigates, comprising twenty-six vessels, was among the most numerous and long-lived classes of frigate in the Royal Navy's modern history. The class was built in three batches between 1959 and 1973...
s with Dutch radars. The British design was chosen in order to enable rapid construction in order to replace elderly destroyer escorts. The ships were modernised in the late 1970s. All six ships were sold to the Indonesian Navy
Indonesian Navy
The role of the Indonesian Navy is to patrol of Indonesia's immense coastline, to ensure safeguard the territorial waters and Exclusive Economic Zone , to protect Indonesia's maritime strategic interests, to protect the islands surrounded Indonesia and to defend against seaborne threats. The TNI...
in 1986-89 and are still in service (as of 2010) as the Ahmad Yani class frigates.
Dutch modifications
For the most part the Dutch limited their changes to the Leander design to a wholesale replacement of the original British electronics and electrical equipment by those from Dutch manufacturers. Hollandse Signaalapparaten supplied the entire electronics suite. Specifically their LW-02 long-range air-surveillance radarRadar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
, the DA-02 medium-range air/surface search radar and the M45 combined radar and optical fire control system for the 4.5 in (11.4 cm) guns. The Dutch HSA M44 radar/visual director for the Seacat
Sea Cat missile
Sea Cat was a British short-range surface to air missile system intended to replace the ubiquitous Bofors 40 mm gun aboard warships of all sizes. It was the world's first operational shipboard point-defence missile system and was designed so that the Bofors guns could be replaced with minimum...
anti-aircraft
Anti-aircraft warfare
NATO defines air defence as "all measures designed to nullify or reduce the effectiveness of hostile air action." They include ground and air based weapon systems, associated sensor systems, command and control arrangements and passive measures. It may be to protect naval, ground and air forces...
missiles could automatically target in elevation and bearing and allowed the single Seacat launcher on the British ships to be increased to two launchers on the Dutch ships, each with their own director.
Mid-life modernization
Beginning in December 1976 each of the Dutch ships was given a mid-life modernization that took about two years to finish. The twin 4.5-inch turret was replaced by a single Otobreda 76 mmOtobreda 76 mm
The Otobreda 76 mm gun is a naval artillery piece built by the Italian defence conglomerate Otobreda. It is based on the Oto Melara 76mm/L62 Allargato, which was bigger and heavier...
gun and two quadruple mounts for Harpoon
Boeing Harpoon
The Harpoon is an all-weather, over-the-horizon, anti-ship missile system, developed and manufactured by McDonnell Douglas . In 2004, Boeing delivered the 7,000th Harpoon unit since the weapon's introduction in 1977...
anti-ship missiles were fitted abaft of the funnel. The Mk 10 Limbo
Limbo (weapon)
Limbo, or Anti Submarine Mortar Mark 10 , was the final British development of a forward-throwing anti-submarine weapon originally designed during the Second World War. Limbo, a three-barreled mortar similar to the earlier Squid that it superseded, was developed by the Admiralty Underwater Weapons...
ASW mortar was replaced by a pair of triple Mk 32 torpedo launchers
Mark 32 Surface Vessel Torpedo Tubes
The Mark 32 Surface Vessel Torpedo Tubes system is a torpedo launching system designed for the United States Navy. The Mark 32 has been the standard anti-submarine torpedo launching system aboard United States Navy surface vessels since its introduction in 1960, and in use aboard the warships of...
, one mount on each side of the hangar, and its mount plated over so the flight deck could be increased to allow the ship to carry the larger Westland Lynx
Westland Lynx
The Westland Lynx is a British multi-purpose military helicopter designed and built by Westland Helicopters at its factory in Yeovil. Originally intended as a utility craft for both civil and naval usage, military interest led to the development of both battlefield and naval variants...
helicopter in lieu of the Wasp carried earlier. The removal of the variable-depth sonar from the quarterdeck to the interior of the stern also allowed more room for the flight deck.
The electronics were also upgraded, the LW-02 radar was exchanged for a LW-03 and the DA-02 was replaced by a DA-05 radar. Most importantly an automated combat management system, SEWACO V, was fitted to aid the ship's captain in decision making. Its power plant was also extensively automated. All told these changes allowed the crew to decrease in size from 254 to about 175 which allowed greatly increased standards of habitability.
Ships
All ships were named after Dutch naval officers. When sold to Indonesia, they were named after Indonesian Armed Forces heroes.| Name | Pennant Number | Builder | Laid down | Launched | Completed | Fate |
|---|---|---|---|---|---|---|
| Van Speijk | F802 | Amsterdam dockyard | 1 October 1963 | 5 March 1965 | 14 February 1967 | sold to Indonesia in 1986 as the Slamet Riyadi (352), an Army Lieutenant Colonel killed in Fort Victoria, Maluku |
| Van Galen | F803 | Royal Schelde | 25 July 1963 | 19 June 1965 | 1 March 1967 | sold to Indonesia n 1987 as the Yos Sudarso (353), a Navy Commodore killed in Battle of Aru Sea i |
| Tjerk Hiddes | F804 | Amsterdam dockyard | 1 June 1964 | 17 December 1965 | 16 August 1967 | sold to Indonesia in 1986 as the Ahmad Yani (351), an Army General killed in 1965 PKI's coup d'état |
| Van Nes | F805 | Royal Schelde | 25 July 1965 | 26 March 1966 | 9 August 1967 | sold to Indonesia in 1986 as the Oswald Siahaan (354), a Navy hero killed in Battle of Sibolga Bay |
| Isaac Sweers | F814 | Amsterdam dockyard | 5 May 1965 | 10 March 1967 | 15 May 1968 | sold to Indonesia as the Karel Satsuitubun (356), a Police officer killed in 1965 PKI's coup d'état |
| Evertsen | F815 | Royal Schelde | 6 July 1965 | 18 June 1966 | 21 December 1967 | sold to Indonesia in 1989 as the Abdul Halim Perdanakusuma (355), an Air Force hero |
Indonesian service
At least some, if not all, of the Indonesian ships have replaced their Seacat launchers with two twin SimbadMistral missile
Mistral is an infrared homing surface-to-air missile manufactured by the European multinational company MBDA missile systems . Based on the French SATCP , the portable missile later to become the Mistral began development in 1974...
launchers. Recently, the two quadruple Harpoon launchers were also replaced by Yakhont missile (SS-N-26) launchers purchased from Russia, because the early version Harpoon missiles previously installed were nearing their obsolescence period. There are also some conflicting reports that the Harpoon missiles were replaced with Chinese-sourced C-802 rather than Russian Yakhont. There are some pictures circulating on the internet showing several vessels of the class carrying box launchers that look much too small to be Yakhont's launchers, but they are the right size for C-802.
Pictures released in March 2011 show that modifications were made to KRI Oswald Siahaan with 4 SS-26 Yakhont VLS cells located in the quarterdeck beside the helicopter hangar.
Engine Replacement
In Indonesian service, the Van Speijk class is known as the Ahmad Yani class after the lead ship. All were named after Indonesian Armed Forces heroes. Between 2003 and 2008, all vessels of the Ahmad Yani class had their existing steam turbineSteam turbine
A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into rotary motion. Its modern manifestation was invented by Sir Charles Parsons in 1884....
engines replaced with diesel propulsion.
| Engine/Gearbox | Power | Replacement date | Shipyard | Ships |
|---|---|---|---|---|
| 2 x Caterpillar Caterpillar Inc. Caterpillar Inc. , also known as "CAT", designs, manufactures, markets and sells machinery and engines and sells financial products and insurance to customers via a worldwide dealer network. Caterpillar is the world's largest manufacturer of construction and mining equipment, diesel and natural gas... CAT DITA 3616, Reintjes WAV 1000 P gearboxes |
16000 hp, (5,450 kW) | 2007–2008 | PT Tesco | 351, 352, 353, 355 |
| 2 x Caterpillar Caterpillar Inc. Caterpillar Inc. , also known as "CAT", designs, manufactures, markets and sells machinery and engines and sells financial products and insurance to customers via a worldwide dealer network. Caterpillar is the world's largest manufacturer of construction and mining equipment, diesel and natural gas... CAT DITA 3612, Reintjes WAF 4566 gearboxes |
12000 hp, (4,060 kW) | 2003 | PT Tesco | 356 |
| 2 x SEMT Pielstick SEMT Pielstick SEMT Pielstick is a French diesel engine manufacturer based in Villepinte, France and owned by MAN Diesel, a subsidiary of MAN AGSEMT Pielstick was formed in 1988 when the business was acquired from GEC Alsthom by MAN and MTU, originally as a 50/50 partnership... 12PA6B, Renk Renk RENK AG is a German company, part of the MAN Group. It has its headquarters in Augsburg, and is producer of gears, other components of propulsion technology and test systems. It is currently the leading manufacturer of transmissions for tracked vehicles, worldwide and a major supplier for marine... SWUF 98 gearboxes |
11800 hp,(4,860 kW) | 2006 | PT PAL/PT Mulia | 354 |