Order 7110.65P, Air Traffic Control, with changes

2/19/047110.65P5−14−8. CONTROLLER INITIATED COASTTRACKSa. Initiate coast tracks only in Flight Plan AidedTracking (FLAT) mode, except “free” coast trackingmay be used as a reminder that aircraft withoutcorresponding computer-stored flight plan informationare under your control.NOTE−1. To ensure tracks are started in FLAT mode, perform astart track function at the aircraft’s most current reportedposition, then immediately “force” the track into coasttracking by performing another start function with “CT”option in field 64. Making amendments to the stored routewith trackball entry when the aircraft is rerouted, andrepositioning the data block to coincide with the aircraft’sposition reports are methods of maintaining a coast trackin FLAT mode.2. DARC does not have the capability to initiate coasttracks.b. Prior to initiating a coast track, ensure thefollowing:1. A departure message or progress reportcorresponding with the aircraft’s current position isentered into the computer.2. The track being started is within the PostedTime Update Interval (PTUI) of the aircraft’scomputer-estimated position and the Flight PlanTrack Position Difference (FTPD) distance of theaircraft’s flight plan route.NOTE−FTPD is an automation parameter, normally set to15 miles, that is compared with the tracked target’sperpendicular distance from the stored flight plan route. Ifthe track is within the parameter miles, it is eligible for“FLAT tracking.” PTUI is an automation parameter,normally set to 3 minutes, that is compared against thedifference between the calculated time of arrival and theactual time of arrival over a fix. If the difference is greaterthan PTUI, the flight plan’s stored data will be revised andfix-time update messages will be generated.c. As soon as practicable after the aircraft is inradar surveillance, initiate action to cause radartracking to begin on the aircraft.Automation− En Route5−14−3