AN/SPG-51
History
The AN/SPG-51 is an guidance radar developed for use with the RIM-24 Tartar missile. This radar was first fitted on the Charles F Adams class destroyer. The first installation was commissioned in in 1960. The SPG-51 is used mostly in combination with the Mk 74 Tartar FCS
As originally developed, SPG-51 had an transmitter that was marginal for the improved (17.5 nm range) Tartar missile. Because of that, the later SPG-51A introduced an much more powerful transmitter. SPG-51B, available from 1963 onwards, introduced speed gate filtering which allowed the radar to track targets trough clutter and at higher noise levels. Most SPG-51B's were later updated to SPG-51C standard. The C standard introduced a major upgrade to the electronics, swapping the vacuum tubes for solid state and reducing the complexity of the system to make maintenance easier and reliability higher. SPG-51D was introduced with the Tartar-D (digital Tartar) fire control system, and had an much upgraded transmitter and some modifications to the base antenna. In this model the transmitter was also moved from behind the antenna to belowdecks.
SPG-51E never reached operational service, and was intended as a universal fire control for both Tartar/Standard and Talos. Talos leaving USN service in the late 1970's made that this development was no longer needed.
The SPG-51D and C have received small updates over time, visible in modifications to the foot on some ships, however the only large change visible on the component is the addition of an antenna to the SPG-51D after the NTU modernisations.
The SPG-51 is still in active use by many foreign navies, but has left US Navy service with the decommissioning of the Kidd class destroyers in 1999. In addition to the Kidd, the SPG-51D is still in service on the Durand de la Penne class. The last ship using SPG-51C, the Cassard class, left service in 2021. SPG-51B and earlier did not last beyond 1995.
Used on
- Charles F Adams class (Built with SPG-51, updated to SPG-51C)
- Albany class (Built with SPG-51 or SPG-51A, unknown if updated)
- Impavido class (Built with SPG-51 or SPG-51A, updated to SPG-51C)
- Mitscher class (Built with SPG-51 or SPG-51A, unknown if updated)
- T47 class destroyer (Anti-air modernisation) (SPG-51B)
- Amatzukaze (SPG-51B)
- Perth class (Built with SPG-51B, updated to SPG-51C)
- Brooke class (Build with SPG-51B, updated to SPG-51C)
- Lutjens class (Built with SPG-51B, updated to SPG-51C)
- Audace class (SPG-51C)
- Baleares class (SPG-51C)
- California class (SPG-51D)
- Tromp class (SPG-51C)
- Virginia class (SPG-51D)
- Kidd class (SPG-51D)
- Cassard class (SPG-51C)
- Luigi Durand de la Penne class (SPG-51D)
Affiliated systems
Part description
The current component has been updated in 2023. As many ships in the archive still have the old SPG-51 drawing, the previous image is kept archived here for reference purposes.
The SPG-51 is drawn in 2 * 5 versions: early SPG-51, SPG-51B, SPG-51C, SPG-51D and SPG-51D after the NTU upgrade. No references for the SPG-51E have been found so that is the only major undrawn version. Of every drawn version, 2 variants are drawn: one without the optional camera and one without it. Of all versions, both sideviews, a front view and a top view are drawn. The top view for each of the 10 variants is included 3 times to facilitate lining it up with the sideview. The deck level and minimal required space under the director are included in the drawing by the use of red outlines.
When using these radars on real designs, please pay close attention to access ladders and equipment on the foot. As this equipment varied over time and from ship to ship, it is not included in the parts but attention should be paid to it to get this component's use fully accurate. Notable is the waveguides on the modernised SPG-51C's on the Charles F. Adams class for example.
The French Navy used an slightly modified version of the SPG-51C on the cassard class, mostly differing in the foot of the radar that was slightly taller.