4.3 Wing Control:
Wing control was one of the earliest forms of missile
control developed, but it is becoming less commonly used on today's designs.
Most missiles using wing control are longer-range missiles like Sparrow, Sea
Skua, and HARM. The primary advantage of wing control is that the deflections
of the wings produce a very fast response with little motion of the body. This
feature results in small seeker tracking error and allows the missile to remain
locked on target even during large maneuvers. The major disadvantage is that
the wings must usually be quite large in order to generate both sufficient lift
and control effectiveness, which makes the missiles rather large overall. In
addition, the wings generate strong vortices that may adversely interact with
the tails causing the missile to roll. This behavior is known as induced roll,
and if the effect is strong enough, the control system may not be able to
compensate.
4.4 Unconventional Control:
Unconventional control systems is a broad category that
includes a number of advanced technologies. Most techniques involve some kind
of thrust vectoring.
Thrust vectoring is defined as a method of deflecting the missile exhaust to
generate a component of thrust in a vertical and/or horizontal direction. This
additional force points the nose in a new direction causing the missile to
turn. Another technique that is just starting to be introduced is called
reaction jets. Reaction jets are usually small ports in the surface of a
missile that create a jet exhaust perpendicular to the vehicle surface and
produce an effect similar to thrust vectoring.
