Enable FlightGear's web interface, open it locally or on another device, and fix connection, port, firewall and security problems.
Start FlightGear with its built-in HTTP server enabled, usually by adding --httpd=8080 to the launcher’s additional options, then open in a browser. Keep FlightGear running: the web interface is served by the simulator and can expose maps, properties and controls, depending on the installed version.
How do I enable the FlightGear web interface?
Enable the interface with --httpd=PORT; starting FlightGear without that option leaves no browser service to connect to.
- Add the HTTP option. Close FlightGear and add
--httpd=8080to the launcher’s additional command-line options. If you start FlightGear from a terminal or shortcut, append the option to the command used to launch it. - Start FlightGear. The HTTP option is processed at startup, so adding it while a flight is already running will not start the server.
- Open the local address. Enter
orin a browser on the same computer. Usehttp://, nothttps://. - Begin at the root page. Follow the map, property or control links provided by your installation rather than relying on an old bookmarked path.
The port number is not fixed: 8080 is a convenient example, but another unused port such as 8081 works if both the startup option and browser address use the same number. Our guide to passing FlightGear startup options explains the launcher and command-line methods in more detail.
What can the browser interface control?
The available tools depend on the FlightGear release, aircraft and web resources included with the installation.
| Web tool | Typical use | Main caveat |
|---|---|---|
| Moving map | Follow the aircraft, route, airports and nearby traffic on another screen. | Map layouts and available layers differ between versions. See our dedicated moving-map setup and usage instructions. |
| Property browser | Inspect FlightGear’s live property tree for aircraft state, systems and troubleshooting. | Changing a writable property can affect the flight immediately, and property paths differ between aircraft. |
| Control or status pages | Operate supported controls or monitor aircraft data from a browser. | These pages are not a full remote desktop and may expose different functions across installations. |
Older documentation may call a FlightGear browser front end Phi or point directly to a particular subpage. Those routes are not consistent across every release, so test the root address first. A missing old path does not mean the HTTP server itself has failed.
The web interface suits human-readable monitoring and occasional control. For a custom app, hardware panel or telemetry recorder that needs structured, continuous data exchange, use the FlightGear UDP interface and protocol setup instead.
How do I open it on a phone or second computer?
Use the FlightGear computer’s private network address and the selected port from another device on the same trusted local network.
- Find the simulator computer’s LAN address, typically resembling
192.168.1.50. - On the second device, open an address such as
. - Allow FlightGear or the chosen TCP port through the host computer’s firewall for private networks only.
- Keep both devices on the same normal Wi-Fi or wired network. Guest Wi-Fi and client-isolation settings commonly block device-to-device connections.
Do not enter localhost on the phone or tablet: that address refers to the phone or tablet itself, not the computer running FlightGear. A VPN can also send local traffic down the wrong route, so disconnect it temporarily when diagnosing a timeout.
Why is the FlightGear web interface not working?
Most failures come from a missing startup option, mismatched port number, firewall rule or obsolete bookmarked path.
| Symptom | Likely cause and fix |
|---|---|
| Connection refused on the FlightGear computer | The HTTP server did not start or the port is wrong. Restart FlightGear with --httpd=8080 and use that same port in the browser. |
| FlightGear reports that the port is unavailable | Another programme is already using it. Select a different unused port in both places. |
| The local page works, but another device times out | Check the LAN address, private-network firewall permission, guest-network isolation and VPN routing. |
| The browser shows an HTTPS or certificate error | Type the complete http:// address. Do not let the browser upgrade it to HTTPS. |
| The root page works, but a saved page returns 404 | The web interface route changed between versions. Return to the root address and use the links supplied there. |
| Pages or controls are missing | The installed front end may not provide them, or its web data may be incomplete. Check FlightGear’s startup log for missing resources and repair the installation if its programme and data files have become mismatched. |
Is FlightGear's HTTP server safe to leave enabled?
Keep FlightGear’s web server confined to your computer or a trusted private network because its pages may reveal simulator data or permit property and control changes.
Do not assume the built-in service provides a login or encrypted HTTPS connection. Avoid router port forwarding, public Wi-Fi exposure and permissive public-network firewall rules. Remove the --httpd option and restart FlightGear when browser access is no longer needed.