Set up FSLTL in MSFS 2020 correctly: install both components, use the right traffic settings, launch the injector and fix common problems.
To set up FSLTL in Microsoft Flight Simulator 2020 on PC, install both FSLTL Base Models and the FSLTL Traffic Injector through the FlyByWire Installer, disable the simulator's own AI or live traffic, load a flight, then start the injector. Keep its console open while flying; the models alone do not generate traffic.
What does FSLTL install?
FSLTL needs two separate components, and a complete installation includes both of them.
| Component | What it does | When it runs |
|---|---|---|
| FSLTL Base Models | Provides the aircraft models and airline liveries used for model matching. | Loaded by MSFS 2020 from the Community package location. |
| FSLTL Traffic Injector | Reads live flight data and creates matching aircraft around your position. | Must be started for each flying session and left open. |
FSLTL is a PC-only solution for MSFS 2020. Xbox cannot run its external injector or install the required Community packages. Our explanation of how model matching supplies real airline liveries covers why the Base Models package is just as important as the injector.
How do I install FSLTL in MSFS 2020?
Install FSLTL through the FlyByWire Installer while Microsoft Flight Simulator is closed, making sure it points to the package location actually used by MSFS 2020.
- Close MSFS 2020. This prevents locked files and ensures the simulator detects the new packages on its next launch.
- Open the FlyByWire Installer. Select the FSLTL product section.
- Check the installation location. It must correspond to the active MSFS package directory. Store, Steam and custom installations can use different paths.
- Install FSLTL Base Models. Allow the download and extraction to finish before closing the installer.
- Install the FSLTL Traffic Injector. The installer normally provides a shortcut or launch control for the injector.
- Apply any offered updates. Base Models and the injector can be updated independently, so check both entries.
A mistake we see constantly is an installer using an old or unused Community folder after MSFS has been moved to another drive. If the packages appear installed but MSFS cannot see them, follow our checks for finding the active Community folder and correcting package structure.
Which MSFS 2020 traffic settings should I use?
Set the built-in aircraft traffic to Off, Ground Aircraft Density to zero and generic AI models to Off before using the FSLTL injector.
| MSFS 2020 setting | Recommended value | Reason |
|---|---|---|
| Aircraft Traffic Type | Off | Prevents MSFS live or offline AI traffic from duplicating FSLTL aircraft. |
| Ground Aircraft Density | 0 | Stops the simulator filling stands with unrelated parked aircraft. |
| Use Generic Plane Models for AI Traffic | Off | Allows FSLTL's matched models and liveries to appear instead of generic aircraft. |
| Multiplayer | Off for initial testing | Removes online players as a possible source of duplicate or conflicting traffic. It can be restored later if wanted. |
Do not select Real-Time Online under Aircraft Traffic Type just because FSLTL uses live data. FSLTL supplies that traffic itself through the injector. Traffic nameplates are optional and do not affect injection.
How do I use FSLTL for each flight?
Load fully into the cockpit first, then start the FSLTL Traffic Injector and leave its console window running until the flight is finished.
- Start MSFS 2020 and load a flight. Wait until the cockpit and airport have finished loading.
- Launch the Traffic Injector. Use its installed shortcut or the launch option provided by the installer.
- Accept or review the injector settings. The defaults are a sensible starting point. Setting names and prompts can vary slightly between injector releases.
- Confirm that it connects. The console should indicate a connection to the simulator and begin finding nearby flights.
- Keep the injector open. Closing its console stops further traffic injection.
- Restart it after a major location change. If you return to the menu, teleport or load at a distant airport, restarting clears stale traffic and rebuilds the local area.
No flight-plan import is required. The injector follows your position and refreshes traffic within its configured radius, so destination traffic on a long flight normally appears as you approach the destination area.
Which FSLTL injector settings matter most?
The default injector configuration suits a first flight, while aircraft limits, injection radius and static traffic are the main controls to change when performance or gate availability becomes a problem.
| Injector control | Effect | When to change it |
|---|---|---|
| Maximum active IFR aircraft | Limits airliners and other instrument-flight traffic. | Lower this first when busy hubs cause main-thread stutters or excessive ATC congestion. |
| Maximum active VFR aircraft | Limits general aviation and visual-flight traffic. | Reduce it if smaller aircraft are overcrowding regional airports. |
| Injection radius | Controls how far around the user traffic is created. | Use a smaller radius when CPU load matters more than seeing distant traffic. |
| Static aircraft percentage | Adds non-moving parked aircraft to fill unused stands. | Set it low or to zero when gates are blocked, especially at detailed add-on airports. |
More traffic is not automatically more realistic. Every moving aircraft adds simulation, ATC and airport-routing work, while extra models and textures also consume graphics memory. At a major hub, reduce active IFR traffic before sacrificing model quality.
Why is FSLTL not showing any traffic?
No FSLTL traffic usually means the injector is not connected, the packages are in the wrong folder, or there are few live flights near the selected airport.
- Base Models are installed but the injector is not running: Base Models only provide visual assets; they never create aircraft by themselves.
- The console does not report a simulator connection: Close the injector, wait until a flight is fully loaded, then reopen it. Make sure only one injector instance is running.
- The injector works but aircraft are invisible or generic: Verify that Base Models are installed in the active package directory and that generic AI models are disabled.
- A quiet airport remains empty: Test at a busy airport during an active real-world period. Changing the simulator clock does not create historical live traffic because the feed follows real-world data rather than an archived timetable.
- Network requests fail: The injector needs internet access for its live feed. Allow it through the operating system's firewall when prompted, but do not disable security software globally.
- Traffic disappeared after teleporting: Restart the injector so it rebuilds traffic around the new location.
How do I fix duplicate aircraft or incorrect liveries?
Duplicate aircraft come from competing traffic sources, while incorrect liveries usually indicate generic models, missing Base Models or an unavailable exact match.
- For duplicates: Keep Aircraft Traffic Type off, Ground Aircraft Density at zero and every other traffic injector closed. Multiplayer can also place another aircraft on top of the corresponding live flight.
- For generic aircraft: Turn off the MSFS option that forces generic AI models, then update or reinstall FSLTL Base Models if necessary.
- For a plausible but incorrect model or livery: FSLTL has probably substituted the closest available match. No model library covers every aircraft and operator combination.
- For blocked gates: Reduce FSLTL static aircraft and check whether the airport scenery includes fixed display aircraft. Scenery-baked aircraft cannot be removed by FSLTL or the MSFS traffic sliders.
- For stuck taxi traffic or repeated go-arounds: Lower the number of moving aircraft. MSFS controls the injected aircraft after creation, so broken taxi links, congested stands and conflicting runway logic are not necessarily injector faults.
How accurate is FSLTL live traffic?
FSLTL reproduces nearby real-world traffic convincingly, but it is not a frame-perfect replay of radar positions and airport operations.
The live feed supplies the flight identity and position used for injection; MSFS then handles taxiing, separation, approaches and runway behaviour. Simulator weather, ATC decisions, missing parking positions and airport taxi networks can therefore make an aircraft deviate from its real counterpart. Our explanation of live feeds, injectors and aircraft model libraries describes where those differences come from.