AN/SPG-59

The AN/SPG-59 was an advanced phased array radar developed by the U.S. Navy starting in 1958. AN/SPG-59 was intended to offer search, track and guidance from a single radar system and antenna as part of the Typhon combat system. Paired with the new Typhon missile, the system was to provide wide-area air defense out to about 110 nautical miles (200 km) from suitable anti-aircraft cruisers. Both the radar and missile proved to be well beyond the state of the art of the era, and the project was eventually canceled in December 1963.

The Typhon Combat System

The Typhon/SPG-59 started as a response to the introduction of sea-skimming anti-ship missiles into service with Soviet Naval Aviation groups. First-generation missile systems like Talos and Terrier used a combination of beam riding and semi-active radar homing (SARH) that required a special targeting radar to illuminate the target through the entire interception. Typical installations included either two or four such illumination radars, which limited the number of simultaneous interceptions. Facing volleys of missiles such systems could easily be overwhelmed. Adding additional radars was possible, but difficult to arrange as the radars were fairly large and required a clear view of the sky, limiting the number of suitable locations. This led to a "specification convergence"; since there could only be a small number of radars, the missile receivers were built to tune in only a small number of potential "channels". That meant that increasing the number of radars would also require the missiles to be updated as well.