Heads-Up Display Modes 35 - Metaboli

84 Air-to-Air Missiles
execute a continuous turn, bleeding speed and energy all the while. The target
may also turn away to place the missile at the beam position as well. In any event,
the target is trying to make the missile expend as much energy as possible, which
shortens its range and its maneuverability.
Conclusion
From this we see that “missile range” is a very complex topic. Merely knowing
that a missile has a 30 km range doesn’t do much good… When fired from what
altitude? When the target is at what altitude? Against what aspect angle? At what
airspeed? Overall, we can draw two main conclusions:
1. The closer you are to the target when you shoot, the better the chances that
your missile will hit the target. Missiles fired at or near their maximum range
(for the given circumstances) are not very likely to hit.
2. Launching from higher airspeed and altitudes significantly increases the
missile’s effective range.
Missile Guidance
The missile’s guidance systems provide input to the missile’s control system,
which in turn maneuvers the missile to intercept the target. Most modern AAMs
are based on homing guidance. When homing, the guidance law is formed in the
missile’s computer using information on target motion. There are three types of
homing: passive, semi-active, and active.
The simplest of these types, passive homing, relies on emissions given off by the
target itself (radio, heat, light, sound). In case of active and semi-active homing,
the target is illuminated (usually by radar or laser), and the homing system guides
on the illumination energy reflected off the target. For active homing guidance, the
missile itself illuminates and tracks the target. Semi-active homing implies that
some source external to the missile (for example, the radar of the launching
platform) illuminates the target.
Some missiles, especially long-range ones, use combined guidance: inertial radiocorrected
guidance and homing on the terminal part of flight. To implement inertial
guidance, the launching aircraft computer feeds into the missile’s control system
information on target coordinates, trajectory, and relative speed.
After the missile has started, its guidance system uses the information about the
relative position of the missile and the interception point computed by the
navigation system. During the flight of the missile, the interception point may
significantly change. For this reason, radio correction supplements the inertial
guidance. This increases the accuracy with which the missile reaches the target
area. Upon approaching the target, the guidance system switches to homing,
passive or active.
To home, a missile needs a device that will receive radiation from a target (sense
it) and track the target. This device, known as a seeker, is located in the nose of
the missile. However, semi-active homers may include a rear receiver for
reception of information from the illuminating platform. Active homers contain a
transmitter and receiver generally located forward. Depending on the type of
radiation received by the missile, the seeker may use infrared or radar.