I see two fixes in the CIFP file that have the same name PERSN.


  1. Given 2 fixes that have the same name but are located in different regions (defined by ICAO code) how does airplane/pilot distinguish between those 2 when respecting flight plan?

  2. According to FAA Procedures for Handling Airspace Matters

e. AIM [Aeronautical Information Management] must not duplicate any radio fix, waypoint, marker beacons or compass locators names.

how come that those fixes have the same name?

  • 1
    $\begingroup$ That is a related question, not a duplicate. By the way, the 2 fixes in the example do not share the same name, even though they are very similar. $\endgroup$
    – bogl
    Commented Feb 6, 2019 at 15:45
  • $\begingroup$ If you try to flight plan with skyvector.com from say KBOS to KLAX (Boston to LA), K70 and PERSON are not valid waypoints. K40 and PERSN are, with PERSN sort of enroute, and K40 way up in Alaska. So a pilot would know something was off. $\endgroup$
    – CrossRoads
    Commented Feb 6, 2019 at 17:07
  • $\begingroup$ @bogl 5-character name which is marked in ARINC docs as Waypoint Ident is PERSN for both. I am trying to understand what makes a fix unique as I though it was id number which is unique. $\endgroup$
    – kkl
    Commented Feb 6, 2019 at 22:13

1 Answer 1


The answer is embedded within the question: The pilot is able to distinguish between the two fixes because they are in different regions.

  • $\begingroup$ Is it possible for IFR system to put fix together with ICAO Code for region? Usually for commercial flights I see plain IDs without any region code (e.g. in FPs from flightaware24) $\endgroup$
    – kkl
    Commented Feb 6, 2019 at 22:24
  • $\begingroup$ That sounds like a good question for a controller or someone who enters flight plans into the ATC system. I'm just speaking from a pilot's perspective, and it should be pretty simple to recognize that one of your waypoints is way off. $\endgroup$ Commented Feb 6, 2019 at 22:38

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