AN/SPG-51

AN/SPG-51

The superstructure of the USS Richard E. Byrd (DDG-23) showing the ship's radars, 1983. There are two AN/SPG-51 directors shown directly in the center of the image.
Country of origin	United States
Manufacturer	Raytheon[1]
Type	Pulse-Doppler radar, Missile fire-control
Frequency	Illuminator: 10.25-10.5 GHz[2] Tracking Radar: 5.45 GHz - 5.825 GHz[2][a]
PRF	4100 pps (surface) 9600-16700 pps (air)[2]
Beamwidth	Illuminator: 0.9° (horizontal), 0.9° (vertical) Tracking Radar: 1.6° (horizontal), 1.6° (vertical)
Pulsewidth	Tracking Radar: 2.1-3.2 μs
Range	Tracking Radar: 100 nmi (190 km)[2]
Azimuth	360° at 12°/s[3][b]
Elevation	-30° to 83°[3][b]
Precision	Fire control quality three-dimensional data
Power	Illuminator: 4000 W[2] Tracking Radar: 1600 W average[2] 81 kW peak[2]

The AN/SPG-51 is an American tracking / illumination fire-control radar for RIM-24 Tartar and RIM-66 Standard missiles. It is used for target tracking and Surface-to-air missile guidance as part of the Mk. 73 gun and missile director system, which is part of the Tartar Guided Missile Fire Control System.[4]

Aircraft tracking is based on monopulse radar utilizing Pulse-Doppler radar signal processing in MK 74 MOD 14 and MK 74 MOD 15. The MK 74 MOD 15 configuration includes continuous-wave radar tracking in addition to pulse-Doppler tracking. It provides illumination for bistatic radar operation associated with missile guidance in all configurations. Older systems rely on conical scanning rather than monopulse.

Platforms

 French Navy

• T 47-class destroyer (Du Chayla subclass post AAW modernization)[5][6]
• Cassard-class frigate[7]

 German Navy

• Lutjens-class destroyer[6]

 Italian Navy

• Audace-class destroyer[6]
• Durand de la Penne-class destroyer[8]
• Impavido-class destroyer[5][6]

 Japan Maritime Self-Defense Force

• Amatsukaze-class destroyer[5]
• Hatakaze-class destroyer[5]
• Tachikaze-class destroyer[6]

 Royal Australian Navy

• Perth-class destroyer[7]

 Royal Netherlands Navy

• Tromp-class frigate[6]

 Spanish Navy

• Baleares-class frigate[7]

 United States Navy

• Albany-class cruiser[9]
• Brooke-class frigate[7]
• California-class cruiser[10]
• Charles F. Adams-class destroyer[6]
• Forrest Sherman-class destroyer (DDG conversion with Tartar)
  • USS Decatur (DDG-31)
  • USS John Paul Jones (DDG-32)
  • USS Parsons (DDG-33)
  • USS Somers (DDG-34)[6]
• Kidd-class destroyer[5]
• Virginia-class cruiser[6]

Variants

• SPG-51: Original Model.
• SPG-51B: Upgraded SPG-51 designed for use with Improved Tartar (IT) missile.[11]
• SPG-51C: Automatic acquisition and tracking, increased reliability, and improved ECCM capabilities, clutter rejection, and multiple target resolution.[1]
• SPG-51D: Klystron replaced with traveling-wave tube to permit the transmission to be chosen from a much wider bandwidth. Increased use of integrated circuitry and digital circuitry.[2]
• SPG-51E: Proposed "universal fire control radar" capable of controlling the RIM-8 Talos as well as Tartar.[1] Not built in quantity.[12]

• 
  AN/SPG-51 radars of a Cassard class frigate

References

1. Friedman, Norman (1981). Naval radar. Annapolis, Md.: Naval Institute Press. pp. 179–180. ISBN 0-87021-967-7. OCLC 8262709.
2. Hemenway, D.F.; Navid, B.N. (September 1978). Reliability of Naval Radar Systems (Report). Washington D.C.: Naval Research Laboratory. pp. 83–88.
3. Winter, Charles F. (Winter 1974). "Mechanically-Scanning Antennas". Electronic Progress. 16 (4): 4. Bibcode:1974ElPr...16....2W.
4. Jane's weapon systems. 1972-73: 4th ed. Ronald Thomas Pretty, Dennis Henry Ross Archer. London: Jane's Yearbooks. 1972. p. 540. ISBN 0-354-00105-1. OCLC 655668873.
5. Jordan, John (1986). An illustrated guide to modern destroyers. New York, N.Y.: Prentice Hall. pp. 58, 70, 77, 79, 134. ISBN 0-13-450776-2. OCLC 13010345.
6. The World's navies. Christopher Chant. Newton Abbot [England]: David and Charles. 1979. pp. 63, 92–93, 104, 122, 229, 231, 241. ISBN 0-7153-7689-6. OCLC 5798981.
7. Combat fleets of the world : their ships, aircraft, and armament, 1986/87. Jean Labayle Couhat, United States Naval Institute (6th ed.). Annapolis, Md.: Naval Institute Press. 1986. pp. 13, 123, 420, 643. ISBN 0-85368-860-5. OCLC 14161346.
8. Jane's fighting ships, 2009-2010 2009/2010. Stephen Saunders (112th ed.). Coulsdon: Jane's Information Group. 2009. p. 395. ISBN 978-0-7106-2888-6. OCLC 652063550.
9. NAVEDTRA 10199-C: Gunner's Mate M 3 & 2. Naval Education and Training Support Command. 1977. p. 147.
10. Jane's strategic weapons systems. Duncan Lennox, Roger Loasby, Jane's Information Group (1st ed.). Coulsdon, Surry, Eng.: Jane's Information Group. 1989. p. 405. ISBN 0-7106-0880-2. OCLC 20284225.
11. "Evaluating the DDG". Proceedings of the U.S. Naval Institute. 91 (7): 749. July 1, 1965. Retrieved February 18, 2023.
12. Friedman, Norman (1989). The Naval Institute guide to world naval weapons systems. United States Naval Institute. Annapolis, Md.: Naval Institute Press. p. 201. ISBN 0-87021-793-3. OCLC 20098065.

Notes

1. All data in infobox is for SPG-51D unless otherwise stated
2. It is uncertain as to which version of the SPG-51 this performance figure comes from.

See Also

• Joint Electronics Type Designation System – Unclassified designation system for United States military electronic equipment
• List of radars
• List of military electronics of the United States

External links

• MK-74 Guided Missile Fire Control System (GMFCS)
• AN/SPG-51D Missile Director Radar