Rear Flap Zones are defined in the GDB:
You can have multiple Zones per track.
Code:
RearFlapZone // zones for using rear flaps in race sessions
{
MinimumCrossings=3 // how many times you must cross the detection under green before it is allowed
TimeThreshold=1.0 // seconds behind another vehicle for it to be allowed
DetectionLapDist=696.7 // distance around track where time threshold is detected
ActivationLapDist=966.1 // beginning of zone where it can be used (if under time threshold is detected)
DeactivationLapDist=1745 // end of zone (yes, the zone can be wrapped around s/f, or not)
}