Van Speijk-class frigate

HNLMS Evertsen (F815) in the 1980s.
Class overview
Name	Van Speijk class
Builders	Nederlandsche Dok en Scheepsbouw Maatschappij Koninklijke Maatschappij De Schelde
Operators	Royal Netherlands Navy  Indonesian Navy
Preceded by	Van Amstel class
Succeeded by	Kortenaer class
Subclasses	Ahmad Yani class
Built	1963–1968
In commission	1967–1989 (Royal Netherlands Navy)
Completed	6
Retired	6 (all sold to Indonesia)
General characteristics
Type	Frigate
Displacement	2,200 tons standard, 2,850 tons full load
Length	113.4 m (372 ft 1 in)
Beam	12.5 m (41 ft 0 in)
Draught	5.8 m (19 ft 0 in)
Propulsion	In Dutch service 2 x geared steam turbines 22,370 kW (30,000 shp) 2 x shafts
Speed	28.5 knots (52.8 km/h; 32.8 mph)
Range	4,500 nmi (8,300 km; 5,200 mi) at 12 kn (22 km/h; 14 mph)
Complement	"before rebuild" 254, "after rebuild" 180
Sensors and processing systems	Radar: "as built" LW-02, DA-02, M45, "after rebuild" LW-03, DA-05, M45, M44[citation needed] Sonar: Types 170B, 162 Combat system: SEWACO V
Armament	"as built" 2 × 4.5-inch guns (1 × twin mounting Mk6) 2 × Seacat surface-to-air missile launcher 1 × ASW Limbo mortar "after rebuild" 1 × OTO Melara 76 mm gun 2 × Seacat surface-to-air missile launcher 8 x Harpoon anti-ship missiles 2 x Mk 32 torpedo launchers
Aircraft carried	1x Westland Wasp, later replaced by Westland Lynx
Aviation facilities	Hangar

The Van Speijk-class frigates were built for the Royal Netherlands Navy in the 1960s. They were versions of the British Leander-class frigates with Dutch radars. The British design was chosen in order to enable rapid construction in order to replace elderly destroyer escorts and take up part of the NATO patrol duties of the decommissioned anti-submarine warfare carrier Karel Doorman. The ships were modernised in the late 1970s. All six ships were sold to the Indonesian Navy in 1986–1989 and five are still in service 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 radar, the DA-02 medium-range air/surface search radar and the M45 combined radar and optical fire control system for the 4.5 in (110 mm) guns. The Dutch HSA M44 radar/visual director for the Seacat anti-aircraft missiles could automatically target in elevation and bearing and because of its much lighter weight, allowed the single Seacat launcher on the British ships to be increased to two launchers on the Dutch ships, each with their own director.^[1]

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 OTO Melara 76 mm 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.^[2]

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.^[2]

Ships

All ships were named after Dutch naval officers.^[1] When sold to Indonesia, they were named after Indonesian National Armed Forces heroes.

Indonesian service

At least some, if not all, of the Indonesian ships have replaced their Seacat launchers with two twin Simbad launchers.^[3] 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.^[4]

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 turbine engines replaced with diesel propulsion.^[5]

Notes

References

Wikimedia Commons has media related to Van Speijk class frigate.

• Adamsn, Thomas A. (1982). John Roberts (ed.). Dutch Leanders: The Van Speijk Class. Warship. Vol. VI. London: Conway Maritime Press. pp. 192–4. ISBN 0-85177-265-X.
• Conway's All the World's Fighting Ships 1947–1995 ISBN 0-85177-605-1
• W.H.E., van Amstel (1991). De schepen van de Koninklijke Marine vanaf 1945. Alkmaar: De Alk. ISBN 9060139976.

This page was last edited on 14 December 2023, at 12:41