Anti-Air missiles (fig. 2-7). The radar system
associated with the Mk 99 MFCS is the missile
illuminator AN/SPG-62.
AN/SPG-62 RADAR.—The AN/SPG-62 is I/J-
Band fire control radar. The SPY-1 radar system
detects and tracks targets and then points the SPG-62
toward the target, which in turn provides illumination
for the terminal guidance of SM-2 missiles. Refer to
chapter 1 for discussion on the different phases of
missile guidance and the way radar is used for missile
guidance. Remember that in order to track a target you
need a very narrow beam of RF energy. The narrower
the beam, the more accurately you can tell if you have
one target or multiple targets (this is called radar
resolution). This narrow beam radar is normally a
second radar that works with a primary search or track
radar. The AN/SPG-62 illuminating radar works as a
second radar with the AN/SPY-1 series radar. See
figure 2-6 for the location of AN/SPG-62 on an AEGIS
cruiser.
In addition to the Mk 99 MFCS, the AEGIS SPY-1
series radar works with the Gun Fire Control System
Mk 86. The Mk 86 GFCS controls the fire of the Mk 45
5-inch gun.
MK 86 GUN FIRE CONTROL SYSTEM
The Mk 86 Gun Fire Control System (GFCS)
provides ships of destroyer size and larger with an
economical, versatile, lightweight, gun and missile fire
control system that is effective against surface and air
targets.
The Mk 86 Gun Fire Control System (GFCS) is the
central sub-element of the Mk 34 Gun Weapons
System (GWS) on AEGIS class ships. It controls the
ship’s forward and aft 5"/54 caliber Mk 45 gun mounts
( fi g . 2 - 8 ) a n d c a n e n ga g e u p t o t wo t a rg e t s
simultaneously. The SPQ-9 series and Mk 23 TAS
(Target Acquisition System) work together to provide
control for Naval Gun Fire Support (NGFS),
Submarine Warfare (SUW) and Anti-Air Warfare
(AW) gun engagements. The Mk 86 GFCS also uses a
Remote Optical Sighting system. This is a separate TV
camera with a telephoto zoom lens mounted on the
mast and each of the illuminating radars. The optical
sighting system is known as ROS on the SPRUANCE
class destroyers and is mounted on the SPG-60
illumination radar. The Mk 34 GWS on AEGIS class
destroyers and cruisers uses the Mk 46 Mod 0 Optical
Sight System on the SPG-62 illuminators.
The Mk 86 GFCS is the controlling element, where
loading and firing orders originate. After an operator
selects the GFCS mode, the system calculates ballistic
gun orders. These orders can be modified to correct for
environmental effects on ballistics. The GFCS
conducts direct firing attacks against surface radar and
optically tracked targets, as well as indirect firing
during Naval Gun Fire Support (NGFS).
2-6
Figure 2-6.—Radar and weapon systems on an AEGIS class cruiser.
Figure 2-7.—SM-2 ER Anti-Air missile on launcher.
