AN/SPQ-9

AN/SPQ-9A, (sometimes pronounced as "spook nine"), is a United States Navy multi-purpose surface search & fire control radar used with the Mk-86 gun fire-control system (MK86 GFCS). It is a two dimensional radar, meaning it provides only range and bearing but not elevation. It can however, also detect and track low altitude (below 2000 ft) air targets.

Initially tested on the USS Norton Sound (AVM-1), it was also deployed on Spruance-class destroyers, Kidd-class destroyers, Ticonderoga-class cruisers, Tarawa-class amphibious assault ships, California-class cruisers and Virginia-class cruisers.

The SPQ-9A is being replaced on all Ticonderoga Class cruisers by the SPQ-9B, which provides twice the range and improved range resolution. This replacement is being done as a part of the United States Navy's "Cruiser Modernization" program to extend the life of the existing ships. The new SPQ-9B will be a part of the Mk-160 Mod 11 gun fire-control system (MK160 GFCS).