The default close air Support Mission
Ysflight includes a close air support mission mode which can be launched either from the "simulation" menu in the ysflight main menu, or online through the "P" key.
The close air support mission makes moving ground objects spawn (generally of the ground type "tank" in the .dat files) in an area designated when the map is made. These objects will move to attack nearby IFF1 ground objects. In the offline mission, the goal is to destroy these objects before they destroy your airbase. In the online mode, the use of the mission has been more creative, and allows the server admin to start a wave of tanks and other objects (which attack ground objects AND aircraft, in many cases) to attack a target.
Tips:
Ground objects from close air support missions are usually pretty spaced out and weak, however there is quite a quantity of them that spawn for a while. Bombs and AGM's are a bit of a waste, because you can't get the maximum effectiveness out of them. 250 pound bombs and high drags might be moderately effective, but rockets are truly kin in this category. Rockets are excellent here because you aren't wasting them if you use them for a single target, they're fast and you can have plenty, and they still have enough radius to take out more than one tank at a time every now and then. Guns are highly ineffective because tanks can take some hits, and the time it takes to properly aim a gun, not waste ammo, and actually kill a single tank is far too long.
For tanks that have air to air defenses such as AAA, your best defense is to fly fast and low, or above 10000 feet. For sam defenses, you might find yourself in a pretty tough spot. It's really hard to aim at tanks from a safe altitude from sams, and a lot of tanks have missiles that don't have a minimum pitch, which means they can alway fire at you. Learn to prioritize these. To better hit the moving tanks, fly in the same line as they're traveling, that way you don't have to yaw and roll to aim your shots if they move out of your weapon's impact point.