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I have noticed that FAA provides data delivery service where both waypoints and ATS routes are available to download. By looking at the files, I realize that there are a variety of waypoints and routes. I really want to pick the particular type of waypoint, which are used for pilots to prepare a flight plan in reality. Could you please let me know which types of waypoints/routes are used in practice?
For reference, I am attaching the screenshot from which the types are categorized.

Types of Waypoint:

Types of waypoints

Types of ATS Routes:

Types of ATS routes

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  • $\begingroup$ What is this screenshot from? $\endgroup$
    – Michael Hall
    Aug 27, 2019 at 16:50
  • $\begingroup$ Hi Michael, this is from a excel file and categorized by FAA. $\endgroup$
    – Sillykim
    Aug 27, 2019 at 22:24
  • $\begingroup$ All of them are used in practice—sometimes. Better question is given aircraft equipment and pilot certificates which can be used in a flight plan, i.e. what is required to actually use each type? $\endgroup$
    – Jan Hudec
    Aug 28, 2019 at 18:07
  • $\begingroup$ Hi Jan Hudec, thank you so much for your comment! I should have asked the better question as you suggested. $\endgroup$
    – Sillykim
    Aug 28, 2019 at 21:54

4 Answers 4

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In real life the flight planning process starts with where you are, where you are going, and then you make decisions on routing based on considerations such as weather, terrain, alternate airfields, airspace, VFR vs IFR, etc. Looking at the chart you will then choose appropriate waypoints along that route of flight based on the aircraft navigation equipment. You don't generally start planning by making a blanket decision on what category of waypoint you would like to use.

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  • $\begingroup$ Thanks Michael for your answer! Would you mind if I ask one follow-up question? When you are saying 'choose appropriate waypoints along the route', what kinds of waypoint would define the route? Let's say that the route is generated by only using RNAV waypoints? or it is possible to have a variety of waypoints such as RNAV and Reporting point in practice? For example, it seems to me that the real flight trajectory (from FlightAware) used three different types of waypoint, which are Waypoint, Reporting point, and NAVAID. $\endgroup$
    – Sillykim
    Aug 27, 2019 at 22:30
  • $\begingroup$ @Sillykim – Both high and low altitude routes have traditionally been defined by ground based Navaids such as VORs, but as GPS becomes ever more prevalent I think you will see more RNAV waypoints used. Typically a “Victor route” (low) or “Jet route” (high) will hop from VOR to VOR. For filing purposes you only need to list the route, and all waypoints along that route are included. Rarely will such a route take you all the way to where you are going, (just like you need to get off the interstate at some point…) so other waypoints are added as necessary. Do you have access to a chart? $\endgroup$
    – Michael Hall
    Aug 28, 2019 at 15:52
  • $\begingroup$ ADDENDUM - It is certainly possible, and as I mentioned before, even preferable to plan your route using a variety of waypoint types on your route. Compare it to driving: You would never plan a trip using only cloverleaf interstate highway intersections, or decide to travel exclusively through flashing 4 way stops. You would choose the most efficient route and intersections compatible with your vehicle type and planned destination. Does this perspective help? $\endgroup$
    – Michael Hall
    Aug 28, 2019 at 17:43
  • $\begingroup$ thank you so much for letting me know that I only need to list the route. If then, I may want to confirm with you that both RNAV and CONV are prevalent to define the routes over US. Please let me correct if I am wrong. $\endgroup$
    – Sillykim
    Aug 28, 2019 at 21:57
  • $\begingroup$ I'm not sure what CONV waypoints are, but RNAV is common. I would recommend you check skyvector.com if you would like to see what kind of waypoints are used in the US. $\endgroup$
    – Michael Hall
    Aug 28, 2019 at 22:04
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Routes were traditionally built using SIDs, airways and STARs, not individual waypoints (aka fixes).

From the departure airport, there will typically be multiple Standard Instrument Departure routes, each spreading out to several "transition" fixes. At the other end, there will be similar Standard Terminal Arrival Routes and transition fixes.

Then you find the best set of airways that lead from the chosen SID transition fix to the chosen STAR transition fix. For brevity, you only list specific fixes where you will change from one route to another.

Note that the shortest path in time (which should also require the least fuel) may not be the shortest in distance due to differences in winds aloft, and some potential routes may be eliminated entirely due to passing through severe weather.

The new "Free Flight" concept is touted as allowing every flight to make up its own route (at least between the transitions) out of seemingly random fixes, i.e. not using airways, but that is currently only available in relatively uncongested areas or altitudes rather than the norm.

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  • $\begingroup$ Hi StephenS, thank you so much for your answer! It was really good for me to know. Would you mind if I ask you one quick follow-up question? So, did you mean that the shortest path in time does not guarantee the fuel-optimum path due to the wind aloft? Let's say we may have a fuel optimum path even if it's not the shortest path in time when departure and arrival points are given? $\endgroup$
    – Sillykim
    Aug 29, 2019 at 18:30
  • $\begingroup$ Of course experiences differ, but I have rarely built a route using SIDS or STARS. Only on a handful of occasions where I know a SID will be assigned have I actually filed for one. And generally once airborne with a tight inertial, on a long flight we would almost always ask for INS direct and most often get it. $\endgroup$
    – Michael Hall
    Aug 29, 2019 at 20:48
  • $\begingroup$ @Sillykim The least time should also require the least fuel since planes usually cruise at a fixed fuel burn per hour. However, the least time may mean a longer distance over the ground with a tailwind than a shorter distance with a headwind. $\endgroup$
    – StephenS
    Aug 29, 2019 at 21:07
  • $\begingroup$ @MichaelHall I'd still rather file a real route than risk an FRC on CD; I'll get the same shortcuts (if any) either way. EFBs make it easy to file routes that others have recently gotten approved fornothers with just a few taps, so why gamble? $\endgroup$
    – StephenS
    Aug 29, 2019 at 21:24
  • $\begingroup$ Sorry, but what is an "FRC on CD"? I agree it is not difficult to file for a SID, but if you would prefer an immediate turn on course then why not file for what you want and fly what they assign? I am not understanding what you mean by "risk" in this case... $\endgroup$
    – Michael Hall
    Aug 29, 2019 at 21:39
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Another way to see what routes are typically used for IFR flights in the US is to use the FlightAware IFR Route Analyzer. You can enter an origin and destination to see the routes from flight plans from the past 24 hours.

Of course, note the warnings:

For IFR flight planning, be certain to note altitude, type of aircraft and verify on terminal procedures that you are eligible for that SID/STAR/routing. [...] This data is for suggestion purposes only. Flights may not have been conducted as filed, aircraft type may be erroneous, or data may contain other errors. You must independently verify validity of data by evaluating traditional flight planning publications to be guaranteed of terrain separation, range (fuel capacity) for your aircraft, potential ADIZ/TFR penetration, and other issues that could be fatally hazardous to the health of you and/or your passengers.

So the utility of this information isn't great. As these routes have been worked out by professional dispatchers based on current conditions, equipment, restrictions, and every other flight planning consideration imaginable, the route you'd plan for your flight may be rather different than what an airline filed 12 hours ago.

But since it seems like you're interested in looking at real-world routes, this tool will allow you to see what those typically look like.

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  • $\begingroup$ Hi Zach Lipton, thank you so much for letting me know this. It would be helpful to me. $\endgroup$
    – Sillykim
    Aug 30, 2019 at 14:42
  • $\begingroup$ @Sillykim FYI, to ping someone, use the @ then type the first couple of characters of their user name. A list of available options will come up and you can click on the one you're after. This will actually give the user notification that he's been pinged (as you just got) so she knows to come back and see what's up. Also, you don't have to ping the author of the Q or A - they're automatically notified, and there are no spaces in the names like @zachlipton (you can only ping 1 person per comment, so he won't get the notification). $\endgroup$
    – FreeMan
    Aug 30, 2019 at 16:07
  • $\begingroup$ @FreeMan Thanks for letting me know it! I feel like becoming more familiar with aviation.stackexchange.com :) $\endgroup$
    – Sillykim
    Sep 2, 2019 at 14:48
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If you go to Skyvector.com and enter Departure and Destination airports, then select Routes, it will show you a preferred routing using waypoints that I think tries to use airways when possible. If you change the altitude, different routes will show up.

In practice, for smaller planes anyway, I think most of us pick routes that will go as direct as possible, not going too far off shore, and not getting too close to Class B when possible. Depends on time of day too, Class B can a lot busier at some times than others.

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  • $\begingroup$ Hi CrossRoads, that's good to know. So, for the small planes, I am guessing that you guys would think more the shortest time path than the fuel optimum path? Or maybe it doesn't matter? Please let me correct if I am wrong. $\endgroup$
    – Sillykim
    Aug 30, 2019 at 14:45
  • $\begingroup$ I think shortest time path would equal fuel optimum path, with shortest time adjusted to avoid long over water legs. Flying down the east coast of the US, the shortest path V 139-268-308 takes you well off shore heading southeast of NYC. NYC airspace is quite large and goes up to 7000 ft, the times we've been VFR and westbound at 6500 ft, we've been cleared to go thru it, flying westward down Long Island, directly over JFK, a few miles over water to Colts Neck VFR, and continuing south from there. I have heard of other folks doing it IFR and getting routed north and west of NYC, so it varies $\endgroup$
    – CrossRoads
    Sep 1, 2019 at 15:31
  • $\begingroup$ Thanks for your information! $\endgroup$
    – Sillykim
    Sep 2, 2019 at 14:50

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