PRM Benefits Control Sequence Typically, PRM is used with dual approaches with  centerlines separated less than 4,300 feet but not less  than 3,000 feet (under most conditions).  [Figure 2-15] Separating the two final approach courses is a No  Transgression Zone (NTZ) with surveillance of that zone  provided by two controllers, one for each active approach.  The system tracking software provides PRM monitor  controllers with aircraft identification, position, speed,  projected position, as well as visual and aural alerts.  The IFR system is flexible and accommodating if pilots  do their homework, have as many frequencies as possible  written down before they are needed, and have an alternate  in mind if the flight cannot be completed as planned.  Pilots should familiarize themselves with all the facilities  and services available along the planned route of flight.  [Figure 2-16] Always know where the nearest VFR  conditions can be found, and be prepared to head in that  direction if the situation deteriorates. A typical IFR flight, with departure and arrival at airports with  control towers, would use the ATC facilities and services in  the following sequence: 1.  FSS: Obtain a weather briefing for a departure,  destination and alternate airports, and en route  conditions, and then file a flight plan by calling  1-800-WX-BRIEF. 2.  ATIS: Preflight complete, listen for present conditions  and the approach in use. 3.  Clearance Delivery: Prior to taxiing, obtain a  departure clearance. 26L 8R  Intersection Alpha  NO TRANSGRESSION ZONE (NTZ) 26R 8L  Intersection Beta  Figure 2-15.  Aircraft management using PRM. (Note the no transgression zone (NTZ) and how the aircraft are separated.) 2-13