On identification of a possible threat to bases within the United Kingdom, the RVAF's chain of defence is alerted by the Early Warning Network. The RVAF Air Defence Battle Manager decides on the most appropriate response to the threat, and if the use of Kestrel is indicated, command passes to the relevant Firing Control Centre(s).
Kestrel may be launched up to thirty minutes before intercept time. On launch, the weapon enters 'acquisition' mode whereby potential targets are tracked and prioritized. Multiple Kestrel launches are coordinated either by the FCC (semi-automatic mode) or by direct infra-red communication between individual weapons (automatic mode). Each weapon can therefore act completely autonomously (in the case of communications black-out) or under a centralized command. If contact with the FCC is lost at any time, Kestrel will enter 'automatic' mode.
After a target is designated and assigned as a priority, the weapon enters 'loiter' mode, which may be maintained for up to 20 minutes. During this time the onboard radar tracks the prioritized target whilst scanning for other threats that may become more immediate. In 'semi-automatic' mode information is relayed back to the FCC, and the weapon may be recalled or reassigned by the Launch commander.
When a threat is confirmed 'Hostile Intent' (according to preset range & velocity criteria or by confirmation from the FCC), Kestrel attempts to IFF the target. If no friendly ping is received, the weapon enters 'engage' mode. This is a completely automatic mode. An intercept trajectory is calculated and the weapon fires to eliminate the threat.
The launch vehicle in the case of an intercept, or the entire weapon in case of an recall, are recovered by parachute. Self-destruct mechanisms exist to prevent any part of the weapon falling into enemy hands.