The AN/SPG-55 was a naval, ship-based fire-control radar developed by the firm Sperry Corporation for the US Navy. The AN/SPG-55 served as the guiding radar for the RIM-67 and RIM-2 Terrier surface-to-air missiles. It functioned in the frecuency range between 5.4 and 5.9 GHz, and, if the need arose, it could also be used as an improvised search radar. The AN/SPG-55 was used on board the Belknap-class cruisers, the Farragut class destroyers, the Kitty Hawk-class aircraft carriers, and Leahy-class cruisers. The Sperry Corporation and the Radio Corporation of America manufactured the following versions: the AN/SPG-55, which was the original model; the AN/SPG-55A, which could also guide semi-active guided missiles; the AN/SPG-55B, which supported beam-riding and homing Terrier missiles as well as newer standard missiles.