Creating custom flight routes in your General Aviation (GA) simulator is one of the most rewarding ways to boost realism, sharpen your navigation skills, and break free from repetitive default flights. Instead of relying on pre-generated flight plans, you can program routes that exactly match your training goals – whether that’s practicing a cross-country trip through mountain passes, flying an instrument approach into a challenging airport, or simulating a real-world weekend trip you’re planning. By understanding how route files work and how to build them, you can turn your simulator into a powerful training tool that mirrors the real-world planning you’ll do as a pilot.

This guide will walk you through everything you need to know: from the core components of a flight route, to the specifics of programming your own files, to advanced tips for adding SIDs, STARs, and hold patterns. We’ll also cover common pitfalls and how to troubleshoot them. By the end, you’ll have the knowledge to create complex, realistic flight plans that make every session more engaging and productive.

Understanding the Core Components of a Flight Route

Before you start programming, you need to understand what constitutes a flight route in a GA simulator. Most platforms – including X‑Plane, Microsoft Flight Simulator, and Prepar3D – use route files that contain a sequence of waypoints, each with a specific position and sometimes associated instructions. Here are the essential building blocks:

  • Waypoints – Specific geographic points defined by latitude and longitude, or by a known identifier (e.g., a VOR or NDB). In GA flying, waypoints can be airports, navaids, intersection fixes, or user‑defined points.
  • Airways – Predefined corridors between navaids, typically used for IFR flight. In a GA simulator, you may choose to follow low‑altitude airways (Victor airways) for realism.
  • Altitude and Speed Constraints – Many route formats allow you to assign desired altitudes and speeds at each waypoint. This is critical for replicating real ATC clearances or practicing specific climb/descent profiles.
  • Route Type – GA simulators distinguish between VFR and IFR routes. VFR routes usually just list waypoints; IFR routes may include airways, SIDs, STARs, and approach procedures.
  • Departure and Arrival Procedures – Standard Instrument Departures (SIDs) and Standard Terminal Arrival Routes (STARs) are common in IFR flying. Including them in your route file adds authenticity and helps you practice instrument procedures.

Each simulator uses a different file format – .pln (MSFS/Prepar3D), .fms (X‑Plane), or .rte (some Garmin‑based add‑ons). The good news is that many of the same principles apply, and you can often convert between formats using free tools.

Step‑by‑Step Guide to Programming a Custom Flight Route

Follow these steps to create a route from scratch, import it into your simulator, and verify it works. We’ll use Microsoft Flight Simulator and its native .pln format as an example, but the workflow is similar for other simulators.

Step 1: Choose Your Route Planning Tool

While you can build a .pln file by hand in a text editor, it’s far easier to use a dedicated flight‑planning tool. These tools provide visual maps, current navdata, and automatic export to your simulator’s format. Popular options include:

  • SkyVector – A free, web‑based planning tool used by many real‑world pilots. It offers real‑world charts, airway routing, and the ability to export .fms or .pln files. (Visit SkyVector)
  • Little Navmap – A powerful, open‑source flight planner with a built‑in moving map, support for multiple simulators, and advanced route editing. It can export to all major formats. (Download at Little Navmap)
  • Navigraph Charts – A subscription service that provides up‑to‑date navdata and incredible chart overlays. Its “SimBrief” integration can even generate full flight plans with SIDs/STARs. (Learn more at Navigraph)

For GA flying, SkyVector and Little Navmap are excellent free choices. If you want the most current navdata (updated every 28 days), Navigraph is the gold standard.

Step 2: Design Your Route

Open your planning tool and set the origin and destination airports. For a GA route, keep it reasonable – something like a 100‑ to 250‑nm flight. Then:

  • Add waypoints by clicking on the map or searching for navaids (VOR, NDB) or intersections.
  • If you want to fly IFR, choose airways that connect your waypoints. Most tools will automatically propose low‑altitude Victor airways.
  • Set departure and arrival procedures if desired. For GA aircraft, you’ll typically use a simple SID or direct routing to the first waypoint, and a STAR or an instrument approach for the destination.
  • Assign altitude and speed constraints as you like. For VFR, you might leave these blank; for IFR, set an initial cruise altitude and assign altitude restrictions at waypoints.

Example: Practicing a VFR cross‑country from KPAO (Palo Alto) to KSBA (Santa Barbara) – you could add waypoints at the San Francisco VOR (SFO), then direct to the Pismo Beach VOR (PSB), then direct to Santa Barbara. Keep the altitude at 4,500 ft (or 5,500 ft for IFR).

Step 3: Export the Route File

Once your route looks good, export it in your simulator’s format. In SkyVector, use the “Send To” function and choose MSFS .pln or X‑Plane .fms. In Little Navmap, go to File → Save Flight Plan and pick the appropriate format. The file will be saved to your Downloads folder or the simulator’s “Flight Plans” directory.

Step 4: Import into Your Simulator

The exact method varies, but here’s how it works in the most common simulators:

  • Microsoft Flight Simulator (2020/2024): Copy the .pln file to your %USERPROFILE%\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalState\MISSIONS\FLIGHTPLANES folder (or use the in‑game World Map → Load Flight Plan).
  • X‑Plane: Place the .fms file in the Output/FMS plans folder inside your X‑Plane directory. Then click “Flight Config” → “Load Flight Plan”.
  • Prepar3D: Put the .pln file in %USERPROFILE%\Documents\Prepar3D v5 Files and load it via the main menu “Flight” → “Load”.

Step 5: Verify and Adjust

Load the route in your simulator and review it on the map or in the GPS. Check for discontinuities (gaps between waypoints), incorrect altitude constraints, or missing procedures. If you see an odd turn or a discontinuity, edit the route in your planner and re‑export. It’s also wise to quick‑fly the first few minutes to ensure the autopilot, if you use one, follows the plan smoothly.

Advanced Techniques for Real‑World Realism

Once you’re comfortable with the basics, taking your route programming to the next level will greatly enhance the training value. Here are a few advanced techniques:

Incorporating SIDs, STARs, and Approach Procedures

Real GA IFR flights almost always use published departure and arrival procedures. Even if you’re flying a small Cessna, you might be assigned a “RNAV departure” or a “SID” in busy airspace. Programming these into your route forces you to follow the chart’s lateral and vertical path – exactly as you would in the real world. Most route planners allow you to select the procedure and automatically insert the associated waypoints. For example, in Little Navmap, you can right‑click the departure airport, select “Procedures,” then choose a SID. The waypoints will appear in your route list with altitude constraints matching the chart.

Building Holding Patterns

Sometimes you’ll want to practice holding – either at a fix (like a VOR holding pattern) or as part of an approach. To program a hold in your route file, you can add a waypoint that defines the fix and then place additional waypoints that create the racetrack pattern. For a DME‑based hold, you might add the inbound radial, the hold length (e.g., 1 minute legs), and a outbound parallel track. Not all simulators support “hold” as a directive in the route file itself, so you may have to manually fly the pattern after arriving at the fix. However, you can still plan the route so that the fix appears as a waypoint with the expectation of holding.

Tip: Use Little Navmap’s “Distance ring” tool to estimate the legs of a hold, then add waypoints at 0.5 nm intervals along the outbound leg. This helps you practice flying the pattern with GPS guidance.

Using Real‑World Charts for Terrain and Obstacle Awareness

When programming a VFR route, it’s not enough to just draw straight lines between airports. Good VFR pilots think about terrain, airspace, and obstacles. In your planning tool (especially Little Navmap with its terrain map overlay), examine the elevation profile along your route. If you’re crossing mountains, make sure your altitude exceeds the highest obstacle by the appropriate margin (500 ft for VFR below 10,000 ft). Also check for special use airspace (MOAs, restricted areas) that you should avoid. You can add custom waypoints to steer around those areas – just like you would in real flight planning.

Programming Alternate Routes and Diversions

That essential “in case of” planning: program an alternate route to a nearby airport and load it into your simulator’s GPS ahead of time. This is invaluable for practicing diversions. You can create a separate route file for the alternate and simply load it during flight. Many GPS units in GA simulators support “activate leg” or “direct‑to” functions, but having a full alternate plan ready is more realistic.

Troubleshooting Common Route Programming Issues

Even with careful planning, things can go wrong. Here are the most frequent problems and how to fix them:

  • Discontinuities (gaps) in the route – Often caused when a route file has a waypoint that isn’t connected to the next one by an airway or direct segment. In MSFS, you might see a “‑‑‑DISCO‑‑‑” in the flight plan display. Fix this by removing the airway between the two waypoints and setting a direct leg, or by re‑exporting with the “fill gaps” option enabled in your planner.
  • Altitude constraint errors – Some simulators ignore constraints that conflict with the aircraft’s performance (e.g., asking a Cessna to climb at 2,000 ft/min at high altitude). Check that your constraints are reasonable: a typical cruise climb for a 172 is 500‑700 fpm. Also ensure cross‑restrictions are not contradictory (e.g., “at 6,000 ft” on the same waypoint as “at 4,000 ft”).
  • Missing waypoints or navaids – This happens when your navdata is outdated. The real‑world aeronautical charts are updated every 28 days. If you use a free planner with old navdata, some intersections or navaids may have been decommissioned. Either update your navdata (via Navigraph or the simulator’s navdata update) or avoid using recently changed fixes.
  • Route file won’t load – Ensure the file extension matches what your simulator expects (e.g., .pln for MSFS, not .xml). Also check that the file was exported with the correct format – sometimes the planner defaults to a different simulator format. Rename or re‑export as needed.

If you run into a cryptic error message, the quickest fix is to rebuild the route in the planner from scratch, using only one airway at a time, and test after each addition. This isolates the problematic element.

Tips for Maximizing Training Value

Finally, to get the most out of your custom routes, keep these best practices in mind:

  • Start with short, simple plans. Even a 20‑nm flight between two familiar airports can teach you how the route programming works. Gradually increase complexity by adding airways, altitude constraints, and procedures.
  • Incorporate real‑world weather. Most simulators allow you to load real METAR data. Flying your custom route in actual weather conditions (high winds, low visibility, icing) turns a practice session into a true “sim” that builds decision‑making skills.
  • Use the route as a script for practicing emergencies. For example, program a route that takes you near an airport where you can practice engine‑out landings, or include a hold at a VOR where you then simulate a radio failure and continue via dead reckoning.
  • Keep a log of your custom routes. Note which ones worked well and which exposed gaps in your knowledge. Over time you’ll build a personal library of training plans – much more effective than flying random default flights.
  • Stay current with navdata. Consider a subscription to Navigraph or use free updates every 56 days (the maximum validity of an IFR flight plan in the US). Using outdated information can cause serious errors if you try to follow a real‑world clearance.

Conclusion

Programming custom flight routes in your GA simulator is not just about convenience – it’s a form of flight‑planning practice that deepens your understanding of navigation, airspace, and aircraft performance. By learning how to build, export, and verify route files, you transform your simulator from a passive game into an active learning environment. Start with a simple direct flight, then gradually add airways and procedures. Experiment with SIDs and STARs to see how they change your approach. Use real‑world data and update your navdata regularly. Before long, you’ll be able to construct any route you can imagine – and fly it with confidence. The skills you develop on screen will carry over into the cockpit when you take to the skies for real.

For further reading, check out the official documentation for Little Navmap’s user guide and the flight planning resources on SkyVector. Also see the Navigraph forums for community‑shared route files and tips.