How do I use GPS in a flight simulator?

To use GPS in a flight simulator, power the avionics, enter or import a flight plan, confirm the active leg, select GPS or FMS as the navigation source, and follow the CDI manually or engage NAV/LNAV. Keep checking waypoint sequencing, because a route drawn on the map is not necessarily active guidance.

This is a general flight-simulator workflow covering Microsoft Flight Simulator 2020 and 2024, X-Plane, Prepar3D, FSX and FlightGear. Exact controls depend more on the aircraft's installed navigator than on the simulator: a Garmin-equipped Cessna, glass cockpit and airliner FMS handle the same task differently.

What does flight simulator GPS actually control?

GPS calculates position and supplies course guidance, but it does not automatically steer the aircraft or control altitude.

You do not tune a GPS frequency as you would a VOR, localiser or ILS. The navigator uses its database to identify airports, fixes, airways and procedures, then sends guidance to a CDI, PFD or flight director. The pilot or autopilot still has to follow that guidance.

Garmin-style displays commonly use magenta for GPS guidance and green for VOR or localiser guidance, but colours and labels are not universal. If you are unsure which system belongs on a particular leg, our comparison of GPS, VOR, localiser and ILS navigation explains when to use each source.

How do I set up and follow a GPS route?

The reliable sequence is to load the route, verify it inside the aircraft, select the correct source and establish an intercept before asking the autopilot to track it.

1. Power the navigator. In a cold-and-dark aircraft, switch on the battery, required electrical buses and avionics master. Check the unit's own power control and display brightness if the screen remains blank.
2. Enter or import the flight plan. Add the origin, destination and intermediate waypoints in the intended order. A route created in the simulator planner may not transfer into every detailed add-on aircraft, so verify it on the cockpit GPS or FMS rather than trusting the planning screen.
3. Inspect the route. Check the departure, airway fixes, arrival, approach and runway. Remove duplicate fixes, but do not automatically delete a DISCONTINUITY; some procedure gaps require vectors or a manual leg.
4. Confirm the active leg. The navigator should identify both the waypoint being flown from and the waypoint being flown to. A route can be stored and visible without being activated.
5. Select GPS or FMS guidance. Use the CDI softkey, NAV-source selector or equivalent cockpit control. General-aviation aircraft often show GPS; airliners normally use an FMS route with LNAV or managed NAV rather than a separate GPS switch.
6. Join the course. Hand-fly towards the CDI or use heading mode to create a sensible intercept. If the aircraft is far from the route or almost parallel to it, NAV may remain armed without capturing.
7. Track the active course. Follow the CDI manually, follow the flight-director command bars, or engage the appropriate autopilot mode. Compare desired track, actual track and cross-track error rather than merely pointing the nose at the waypoint.
8. Watch waypoint sequencing. The active waypoint should advance after each fix. If it does not, check for OBS, SUSP, a hold, a manual procedure leg or an unresolved discontinuity.

For cockpit-specific controls, see our G1000 route-entry and active-leg instructions. Older Microsoft simulator users can follow the separate FSX GPS and flight-plan workflow.

Which GPS command should I use?

Choose the command according to how you are joining the route; Direct-To, Activate Leg and Activate Approach are not interchangeable.

A mistake we see constantly is selecting Direct-To when Activate Leg is required. Direct-To creates a new course from the aircraft's present position; it does not necessarily preserve the published or planned inbound track.

Why is the route on the map but not active in the cockpit?

A line on the map can represent a planned or external route that has never been loaded and activated in the aircraft's navigator.

• Different flight plans: the simulator map, tablet or external panel is showing one plan while the panel GPS contains another.
• No active leg: the route exists in the catalogue but has not been activated, or the destination alone has been selected without a course.
• Wrong NAV source: the moving map shows GPS data while the CDI remains set to VOR or localiser.
• Direct-To changed the route: the cockpit navigator is flying directly to one fix while the map still displays the original sequence.
• Procedure mismatch: the simulator and aircraft may use different navigation data, producing missing fixes, changed transitions or a different runway procedure.
• Map orientation: north-up, track-up and heading-up views make the same route look different. Wind can also leave the aircraft's nose visibly offset from its ground track.

Treat the active waypoint, CDI and flight-mode annunciator as the controlling evidence. A magenta line by itself does not prove that the flight director or autopilot is receiving guidance.

Can the autopilot follow GPS with NAV or LNAV?

Yes. The autopilot can follow GPS when a valid leg is active, the correct navigation source is selected and NAV, LNAV or the aircraft's equivalent lateral mode has captured the course.

• NAV: commonly follows whichever source is selected on a general-aviation CDI or PFD, so it may track GPS, VOR or localiser guidance.
• LNAV: normally follows the active lateral route calculated by an airliner or advanced FMS.
• HDG: follows the selected heading bug; use it to create an intercept, then arm NAV or LNAV.
• APR or APPR: is intended for compatible approach guidance, not ordinary en-route GPS tracking.

Read the flight-mode annunciator after pressing a button. An armed mode is waiting to capture; it is not yet steering the aircraft. Wording and colours vary, so look for the mode moving into the active field rather than assuming that a button light confirms capture.

If capture fails, check the source, active leg and intercept angle before pressing NAV again, as a second press can disarm the mode in some aircraft. Our guide to autopilot modes, arming and route capture covers the aircraft-control side in more detail.

How do I use GPS for an approach?

Load the exact runway, approach and transition, verify every fix and altitude, then join the procedure using the correct active leg rather than activating it indiscriminately.

1. Load before activating. Loading places the procedure in the flight plan for checking. Activating it too early can bypass the arrival or send the aircraft directly towards an unsuitable approach fix.
2. Check the transition. Select the initial fix or vectors option that matches your position and clearance. Confirm that the resulting waypoint order makes sense.
3. Verify restrictions. Compare displayed courses, altitude constraints and missed-approach legs. Do not assume every constraint imported correctly.
4. Join the correct leg. Use heading mode for vectors or Activate Leg when intercepting a defined segment. Avoid Direct-To if preserving the published inbound course matters.
5. Confirm approach guidance. For an RNAV approach, keep GPS/FMS selected and check that the simulated navigator has entered the appropriate approach mode. Lateral magenta guidance alone does not guarantee vertical guidance.

An ILS is different. GPS can guide the aircraft to the approach, but final localiser and glideslope tracking normally requires the ILS frequency and a VOR/LOC source. Some integrated systems tune and switch automatically; other aircraft require both actions from the pilot.

Available RNAV guidance depends on the procedure, navigation database and simulated avionics. An approach offering only lateral guidance will not produce a coupled descent path merely because it appears on the moving map.

Does GPS control altitude and descent?

Basic GPS is lateral guidance only; it does not control altitude unless the aircraft has a compatible VNAV or approach-guidance system coupled to the flight director or autopilot.

• Advisory VNAV: calculates a top of descent or required vertical speed, but leaves pitch and descent control to the pilot.
• Coupled VNAV: can follow a calculated vertical path when route constraints, performance data and the correct mode are set.
• Approach glidepath: may provide vertical guidance for a compatible RNAV approach, but it is distinct from en-route VNAV.
• ILS glideslope: is radio guidance rather than GPS guidance, even when the GPS provided the route to the final approach.

An altitude constraint displayed beside a waypoint is not proof that the aircraft will obey it. Check the active vertical mode and selected altitude, and manage the descent manually when the installed system provides advisory guidance only.

What should I check if the GPS is blank, frozen or pointing the wrong way?

Start with electrical power and display brightness, then check the active leg, source selection and sequencing state before treating the problem as a GPS signal failure.

• Blank screen: check the battery, avionics master, electrical bus, unit power control and dimmer.
• Aircraft position does not move: check for a simulated avionics failure, paused avionics, an uninitialised add-on system or a frozen cockpit display.
• CDI points away from the visible route: verify the active from-to leg and whether Direct-To has replaced the planned course.
• Waypoint never advances: cancel OBS or SUSP if it was not intentionally selected, and inspect the next leg for a hold or manual discontinuity.
• Autopilot turns the wrong way: disconnect or use heading mode, stabilise the aircraft, then correct the source and active leg before re-arming NAV or LNAV.
• Procedure is missing: the installed navigation database may not contain that runway, transition or approach. Do not substitute a similarly named procedure without checking its fixes and course.