FSX & FSX: Steam Edition 4 min read

How do I enable AI aircraft and ground vehicles in FSX?

Adam McEnroe
In short

Enable AI aircraft and ground vehicles in FSX, choose the correct Traffic settings, and fix empty airports or missing moving vehicles.

In FSX and FSX: Steam Edition, open Settings > Customize > Traffic. Raise Airline traffic density and General aviation traffic density above 0%, then set Airport vehicle density to Low or higher. Apply the changes and reload the flight if traffic does not appear. Road vehicles use a separate slider.

How to turn on FSX AI traffic and airport vehicles

  1. Open the Traffic settings. From the main screen, select Settings > Customize > Traffic. During a flight, press Alt to reveal the menu, then use Options > Settings > Display and open the Traffic tab.
  2. Enable airline AI. Move Airline traffic density above 0%.
  3. Enable general aviation AI. Raise General aviation traffic density if you want light aircraft and other scheduled GA movements.
  4. Enable moving airport vehicles. Set Airport vehicle density to Low, Medium or higher. Low is a sensible starting point.
  5. Enable road traffic separately. Raise Road vehicles only if you also want cars and lorries on scenery roads. This setting does not control vehicles on the airport apron.
  6. Apply the settings. Select OK. If the existing flight remains empty, reload it at a busy default airport and allow the traffic system time to initialise.

These are global display settings, so stock traffic does not require edits to aircraft.cfg or the traffic files merely to switch it on.

What does each FSX traffic setting control?

SettingWhat it controlsWhat it does not control
Airline traffic densityScheduled airliner flight plansInstalling aircraft, liveries or new routes
General aviation traffic densityScheduled light-aircraft and GA trafficThe player aircraft or unscheduled parked aircraft
Airport vehicle densityMoving service vehicles using airport vehicle pathsRoad traffic, jetways or static scenery objects
Road vehiclesCars and lorries on supported scenery roadsRamp and apron vehicles
Ships and ferries or leisure boatsMarine trafficAny airport activity

The AI percentages are filters applied to compiled traffic schedules; they are not targets for gate occupancy. Setting airline traffic to 30% does not mean 30% of every airport's stands will be filled. To introduce particular aircraft, airlines or routes, follow our guide to creating custom FSX AI traffic schedules.

Why are AI aircraft still not appearing?

A non-zero slider only permits installed traffic to run; it cannot create missing aircraft or schedules. Test at a large default airport during daytime before assuming the setting has failed, as a small airfield may have few or no active departures at the selected time.

  • Confirm both AI sliders are above 0%. Airline and general aviation traffic are controlled independently.
  • Check the traffic files. AI requires an enabled traffic BGL containing valid schedules and airport identifiers.
  • Check the aircraft models. An add-on schedule cannot display an aircraft whose model is missing or installed in the wrong FSX folder.
  • Check older traffic packages. An FS2004-format traffic BGL can interfere with FSX-format traffic. Convert or remove the older file rather than mixing formats.
  • Consider parking availability. Aircraft may fly but fail to appear at gates when the airport lacks parking spaces of the required size or type.

If the problem began after installing a World of AI package, use our WOAI installation and traffic-BGL troubleshooting checks.

Why are airport ground vehicles still missing?

Airport Vehicle Density produces moving vehicles only where the airport scenery contains a suitable vehicle network. A small strip with no vehicle paths can remain empty even at the highest setting, while an add-on airport may use its own animation system instead.

Static baggage carts, fuel equipment and decorative vehicles are scenery objects rather than traffic. They will not disappear or multiply when Airport Vehicle Density changes; our explanation of static versus moving FSX ground equipment covers that distinction.

Which traffic settings give a good balance?

Start with both AI aircraft sliders around 20–30% and Airport Vehicle Density on Low, then increase one setting at a time. Dense airline traffic is most visible at major hubs, while GA traffic matters more at regional fields and flying clubs.

  • For airliner operations: prioritise airline traffic, keep GA moderate and leave road traffic low.
  • For general aviation: favour the GA slider and reduce airline density if large hubs are not important.
  • For limited performance: reduce road vehicles first, then airport vehicles and AI density as needed.

FSX must calculate each active AI aircraft, its route and its ground movement, so high settings can reduce frame rate sharply around complex airports. Our FSX performance-tuning advice explains which traffic and scenery options to lower when a busy airport becomes too demanding.

AI Assistant New

Still stuck? Ask Fly Away

Ask Fly Away is our AI flight-sim assistant. Ask your exact question and get a direct, step-by-step answer in seconds — free to try.

Ask Fly Away Free preview · unlimited for PRO members