The MK 92 Fire Control System (FCS) is deployed onboard FFG 7 PERRY-Class ships in conjunction with the MK 75 Naval Gun and the MK 13 Guided Missile Launching System. The MK 92 FCS integrates target detection with multichannel antiair and antisurface missile and gun systems control, engaging up to four targets simultaneously. The MK 92 track-while-scan radar employs the Combined Antenna System (CAS), which houses both search antenna and tracker antenna inside a single egg-shaped radome. A Separate Target Illumination Radar (STIR) designed for the PERRY-class MK 92 FCS application provides a large diameter antenna for target illumination at ranges beyond CAS capabilities. The MK 92 FCS is in service with a number allied fleets, and in additional cases, is onboard US Navy FFG 7-Class ships slated for transfer to international navies.
The Mod 1 system in PHMs and the US Coast Guard's WMEC and WHEC ships can track one air or surface target using the monopulse tracker and two surface or shore targets using track-while-scan data from the Combined Antenna System (CAS). The Mod 2 system in FFG 7 class frigates can track an additional air or surface target using the Separate Track Illuminating Radar (STIR). Collimation is the RF to Optical alignment of the fire control radar. It is necessary to ensure the track RF andC WI beams are aligned with the director, along with the CWI power density measurement, to accurately deliver ordnance on target. Collimation is performed whenever the CAS track antenna, STIR reflector, or the STIR director is removed for refurbishment. Collimation is often confused with battery alignment (STAV). While it is an independent alignment of the radar, STAV is the mechanical and electrical alignment of the ship's weapons systems, comprised of the MK 75 Gun Mount, the MK 13 GMLS, CAS, STIR, etc. STAV is performed to ensure all the weapons systems are aligned to the same traverse plane reference.