Out of all of the addons that I’ve tried FSX, here are the best free ones I’ve found to date:
- FreeMeshX. Updated terrain information from NASA for the entire world. Essentially makes mountains, hills, and so on look more realistic. This should be the first thing you install if you plan on flying outside of the USA.
- The Just Flight Boeing 757-200. Free British Airways and American Airlines liveries.
- The Basler BT-67. A super cool retrofitted DC-3
- World of AI ATC. Adds AI aircraft from real airlines to your airports.
- Plan-G. A vastly superior alternative to the default FSX flight planner
- Simbrief. Makes flight plans based on real commercial routes.
- Flightaware. Not an addon, but you can see real commercial flight plans, and flightaware can also propose realistic flight plans for you. Also has approach plates for most airports.
- FSX Navdata update. The defaults with FSX are old.
- FSCaptain. You work as a commercial pilot. FScaptain assigns routes for you and grades your performance, and adds a copilot and flight crew. Technically shareware, but you can get a lot of mileage out of the free version.
- Jordan King freeware terrain and scenery recommendations.