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I know ATS routes are made up of waypoints, but what are Significant Points used for? Is there a difference, or are they really just two names for the same thing?

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According to ICAO PANS-ATM (Doc 4444) 16th Edition,

Waypoint is a type of significant point.

Mentioned in Chapter 1 - Definition as

Significant point :- A specified geographical location used in defining an ATS route or the flight path of an aircraft and for other navigation and ATS purposes. Note.— There are three categories of significant points: ground-based navigation aid, intersection and waypoint. In the context of this definition, intersection is a significant point expressed as radials, bearings and/or distances from ground-based navigation aids.

Waypoint is defined as a specified geographical location used to define an area navigation route or the flight path of an aircraft employing area navigation.

So in short waypoint is a significant point used to define an area navigation route or the flight path of an aircraft employing area navigation

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  • $\begingroup$ This is the book definition, but they sound very similar to me. The OP asked "are they really just two names for the same thing?" It would appear to me that they are. Can you offer a practical example of how they might be used differently? It would help to have some context. $\endgroup$ Aug 22 '20 at 15:13
  • $\begingroup$ A VOR reporting point on a conventional ATS route (Non RNAV ) is a significant point but not a waypoint if it is flown by an aircraft not employing area navigation. $\endgroup$ Aug 23 '20 at 18:09
  • $\begingroup$ it is a waypoint if you put it in your flight plan and fly to it. I have never heard anybody ever refer to a point on their flight plan as a “significant point”. In normal use, if it is in your route of flight it is commonly referred to as a waypoint, fix, intersection, turn point, or NTP, (Nav Turn Point). This is of course based solely on personal experience, so I cannot make any claim beyond 4 decades of flying, mainly in the US. Other country’s pilots may very well use the term “significant” in normal conversation. $\endgroup$ Aug 23 '20 at 18:28
  • $\begingroup$ The question was about the difference between these two terms. It doesn't matter whether pilots uses this term in normal conversations. ICAO PANS-ATM uses 'significant point' term whenever the rules or separations are based on either a waypoint or a nav-aid. A nav-aid becomes a waypoint only when you put the nav-aid coordinates in FMS and fly. If an aircraft without FMS onboard flying by tuning in to a VOR onboard, then it's a significant point and not a waypoint and separations methods mentioned in PANS-ATM for aircraft employing area navigation may not be applied between such aircraft. $\endgroup$ Aug 24 '20 at 3:09
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    $\begingroup$ @Michael Hall. Separation methods and minima depends upon the navigational aid and capability of aircraft especially in non-radar environment. ATC gets alerts and warning from automation systems when an aircraft is not equipped with right equipments for the airspace they are flying. An aircraft having no GPS / VOR board cannot be separated using VOR lateral separation minima mentioned in PANS-ATM even though it is difficult to find an aircraft in such a condition. So there comes the importance of significant points and waypoint. $\endgroup$ Aug 25 '20 at 4:05

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