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First, an aircraft must be detected, which in itself can be difficult in a high electronic stimulus environment. Once the detection is made, a track must be developed and refined to provide range, bearing, altitude, and velocity. While maintaining and refining the track, a weapon system must be assigned to destroy the adversary. Once the decision on weapon system is made, quality track data must be handed off to the surface-to-air missile or fighter. The weapon system must acquire and lock on to the incoming bomber.
Finally, when the bomber is in range, the SAM or fighter can fire their weapon. This is a complicated sequence of events that stealth technology further complicates.
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