International Aerobatic Club
The International Aerobatic Club (IAC) is a division of the Experimental Aircraft Association (EAA) and the National Aeronautics Association (NAA). It promotes aerobatics and governs the sport of competition aerobatics in the United States under the regulations of the Fédération Aéronautique Internationale (FAI).
Source: Wikipedia — International Aerobatic Club (CC BY-SA 4.0)