Flightplan has a list of the aircraft that come with the Basic version of Microsoft Flight Simulator 2020 for convenience (future versions may contain addtional aircraft) but it would be impossible to keep the list in sync with every aircraft in the Marketplace. So the name of any aircraft you own can be typed into the field and saved on any flight plan. Simply type the exact name any aircraft in your hanger in Microsoft Flight Simulator. If you are unsure of the exact name (especially for aircraft that have multiple configurations, wheels vs. floats for example) just create a flight plan from World Map in the game and save it to your local PC, then open it in Flightplan.
By saving a flight from within Microsoft Flight Simulator 2020 World Map you will ensure that any parameters specific to the aircraft (ex: fuel tank configuration or weaponry on military aircraft) are saved in the flight plan. Flightplan preserves ALL parameters in a flight file (.flt) regardless of how the file was originally created. So once you’ve saved a flight for an aircraft once, you can make copies of that flight plan and change the airports, waypoints, etc. and all of your aircraft parameters are preserved in the new copies.
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