target rounds

Time On Target (TOT) is the military co-ordination of artillery fire by many weapons so that all the munitions arrive at the target at roughly the same time. The military standard for coordinating a time-on-target strike is plus or minus three seconds from the prescribed time of impact.
In terms of target area, the historical standard was for the impact to occur within one circular error probable (CEP) of the designated target. CEP is the area on and around the target where most of the rounds will impact and therefore cause the maximum damage. The CEP depends on the caliber of the weapon, with larger caliber munitions having greater CEPs or greater damage on the target area. With the advent of "smart" munitions and more accurate firing technology, CEP is now less of a factor in the target area.
In terms of time, Time on Target is also a reference to the period of time that a radar illuminates a target during a scan. It is closely associated with Dwell period. There may be multiple dwell periods within the Time on Target period.

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