The A-10, as jaedub pointed out, is a Close Air Support craft.. it's purpose is to fly low and slow over a battlefield, and pulverize anything that threatens the ground troops, as well as targets of opportunity. It has a loiter time of around 2 hours more or less, depending on how far it has to go after mid-air refueling to reach the combat zone. It is extremely durable, and there are reports of it taking direct missile hits and flying home, as well as 57mm AAA shots to the bottom of the cockpit, which did not penetrate its titanium armor (IIRC). It has multiple redundant controls, as well as manual controls in case the hydraulics get shot up. The wheels are made to that they will drop into the craft's slipstream and lock if the hydraulics are gone and they have to be released manually. Even though this is its primary purpose, it can maneuver sharply at low speeds, and it carries some Air-to-Air weaponry (2x AIM-9 Sidewinders, plus, of course, the cannon).