Learn what flight simulator navdata contains, how AIRAC cycles work, where to install updates, and how to fix mismatched FMC and planner cycles.
Flight simulator navdata is the database of waypoints, radio aids, airways, airport identifiers and instrument procedures used by route planners and aircraft avionics. Keep it current by using the supported AIRAC update method for the simulator and any add-on FMS, then verify that every component reports the same cycle.
What does flight simulator navdata contain?
Navdata supplies the coded information an FMS, GPS, flight planner or simulator ATC system needs to construct and follow a route. Depending on the database and simulator, this can include:
- Airport, runway and navigation-aid identifiers
- VOR, NDB and localiser frequencies and positions
- Intersections, reporting points and airways
- SIDs, STARs, approaches and their transitions
- Altitude, speed and course constraints encoded into procedures
Navdata is not the same as scenery. It does not normally replace runway textures, terminals, terrain, buildings or satellite imagery, and an AIRAC package does not automatically include human-readable charts. Simulation navdata must never be used for real-world navigation.
What is an AIRAC cycle?
AIRAC is the aviation industry schedule under which significant navigation changes take effect on coordinated 28-day dates. Flight-simulation databases commonly identify a cycle using YYCC, where the first two digits represent the year and the last two identify that year's cycle.
An expired cycle does not suddenly stop working. It means the database may not contain newer waypoints, renamed airways, runway changes or revised procedures. More importantly, two databases from different cycles can disagree with each other.
Do you need the latest AIRAC cycle?
You should use a recent, matching cycle when flying present-day IFR routes, importing plans from another tool or using online ATC. For casual VFR flying or an older, self-contained simulator installation, updating every 28 days is rarely necessary.
Consistency matters more than the newest cycle. A planner and FMS using the same older data will usually produce fewer errors than a current planner feeding procedures into an aircraft with a much older database. AIRAC data is licensed, so use an authorised source; our explanation of which no-cost AIRAC update routes are legitimate covers the safe alternatives to unauthorised copies.
How do you update flight simulator navdata?
- Identify every database in use. Check the simulator's map or ATC system, the aircraft FMS, any external planner and any avionics add-on. These may all be separate products.
- Record their active cycles. An airliner's FMC usually shows this on an IDENT, STATUS or NAV DATA page. GPS units and planners normally expose the database date or cycle in an information or settings page.
- Choose the correct package. Use the simulator's official content update where that controls navdata, or select the exact simulator, version and aircraft target in a supported AIRAC installer. A package for one aircraft will not necessarily update another.
- Close the simulator before installation. Back up manually modified data, remove obsolete packages when instructed and avoid combining files from different cycles. On consoles, file-based desktop installers are generally unavailable, so updates must come through the simulator or supported add-on system.
- Restart or rebuild the database. Some simulators index navigation files at launch; others require a cache refresh after replacement. Let that process finish before loading a flight.
- Verify more than the cycle label. At a familiar airport, compare one SID, STAR or approach between the planner and cockpit. Matching cycle numbers do not help if the update was installed into a folder the aircraft never reads.
- Align the rest of the toolchain. Update the planner and aircraft databases together where possible, then recreate any flight plan that was generated from the old cycle.
Where does each simulator get its navdata?
| Simulator family | What normally needs updating | Common gotcha |
|---|---|---|
| Microsoft Flight Simulator | Core simulator navdata and, where applicable, an aircraft-specific database | Updating the world map does not guarantee that every add-on FMS uses the same source. Follow our MSFS package and cycle-verification steps. |
| X-Plane | The user override in Custom Data, plus any separate aircraft database | Replacing default files instead of using the override folder can leave the update ineffective or make it vulnerable to repair and update processes. See the correct X-Plane Custom Data workflow. |
| Prepar3D and FSX | Flight-planning data, scenery-derived records and each add-on FMS may be independent | There is no single universal update that refreshes every aircraft and utility. Our Prepar3D add-on database procedure explains how separate targets are handled. |
| FlightGear | Core navigation files and, for some aircraft, a separate avionics database | Updated data may not appear until the navigation cache has been rebuilt or the simulator restarted. |
Why do the FMC and flight planner show different navdata?
The usual cause is that the planner and aircraft are reading different databases. Updating the simulator alone often leaves an advanced add-on aircraft on its previous cycle, while updating that aircraft may leave the simulator's map and ATC unchanged.
NAV DATA OUT OF DATE: the simulated date falls outside the database's validity period. Install the appropriate cycle for present-day flying; for a historical flight, the warning may be expected.- A procedure appears in the planner but not the FMC: check both cycle numbers, the selected runway and the aircraft's own database target. Some avionics also filter procedures they cannot interpret.
- The installer reports success but nothing changes: the wrong product profile, simulator version or library folder was probably selected. Duplicate custom packages and stale indexes can produce the same symptom.
- An imported route contains unknown waypoints: rebuild it with a planner using the same cycle as the aircraft, or enter a route using fixes that exist in both databases.
Does updating navdata update airports and runways?
No. Navdata can change an airport identifier, runway record, frequency or procedure coding, but it does not redraw the airport. After a real runway renumbering, for example, the FMS may show the new number while older scenery still paints the previous number on the ground.
When the cycle matches but the visual airport does not, the remaining problem is scenery rather than navigation data. Compare one procedure and runway in both the planner and cockpit first; if those agree, investigate the airport scenery, plan-import format or avionics limitations instead of repeatedly reinstalling the AIRAC package.