It's Falcon BMS 4.33, a free modification of Microprose's Falcon 4.0 (available on GOG as Falcon Collection in case you missed it). It is one of the best combat flight sims out there but it requires great amounts of dedication (the learning curve is nothing short of staggering and you must be armed with patience as you go through the manuals/tutorials on Youtube/actual training) and a good joystick. Head tracking will be helpful too since you won't be needed to grow a third (or fourth) hand, but not critical to learn and play the game.

The campaign is dynamic and it is great; it runs alongside the game and whatever you do has an impact on the outcome of the war. The F-16, being a multi-role aircraft, allows for a number of different missions such as A-A, DEAD, SEAD etc. so you won't get bored, especially since everything feels "alive" and you may find that careful planning is one thing while sticking to it and finding things aren't what you expected them to be is another.

BMS may be hardcore, but it rewards you with some of the finest and most realistic modern combat flight action there is. You can check out some videos such as this (youtu.be/JFo6uYweVGg) and this (youtu.be/o5U67Qs7OI8) on YT to get a glimpse of the action and since it is free, just go download it and see for yourself. ;)