GPS is fairly simple. To file a flightplan from one place to another go to File > Flight Planner. Configure your DEPARTURE and ARRIVAL cities. Also, if you plan to have a little flight "emergency" you might want to choose your ALTERNATE airport.
After all that's done, click HIGH ALTITUDE AIRWAYS if you are flying over 18000ft, else, LOW ALTI' AIRWAYS or VOR TO VOR if you want FPlanner to chart using VOR.
Click FIND ROUTE to have your route plot, where you can view or edit points on your route simply by dragging the route (line) to any desired green waypoints or blue VORs (I do this to make sure my aircraft turns and aligns with the runway on approach)
Click OKAY when you're done.
To view your flightplan, click the small button that looks like a radar (GPS)--on your instrument panel.
Takeoff from the runway. After 1000' , enable autopilot press NAV or NAV1 on the autopilot to have the aircraft follow the route on your flight planner. Also, turn the switch from NAV to GPS. The switch is found below the HSI screen.
For a detailed description on how to use the GPS and Flight Planner, search FS2000 help on the topic "Flight Planner"
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