Spawning an aircraft flyover via trigger

[Delicious 10]

Hello,

I would like to have an aircraft fly over a specified area (and then be dismissed via waypoint) but I'm unsure how to go about this.

I currently have a number of aircraft, each with a waypoint near them synchronized to a trigger, so that when I activate the trigger the aircraft flies past my position and then is dismissed at a later waypoint.

Instead of synchronizing the trigger to the first waypoint however, I would prefer to only bring the aircraft into actual existence after the trigger has been activated. This prevents the aircraft hanging around the initial waypoint and getting into all sorts of trouble on their own :)

Any help would be appreciated! :)

Delicious