The Rans S-9 Chaos is an American single-engined tractor configuration single-seat mid-wing monoplane designed by Randy Schlitter for aerobatics and manufactured by Rans Inc. The Chaos is available in kit form for amateur construction. Production of the S-9 was ended as part of Rans' reorganization of its product line on 1 June 2006 after having been available for 20 years but the S-9 was reintroduced in about 2009 and is again available.
Made by Rans Designs.
Rans S-9 Chaos is the predecessor of the Rans S-10 Sakota.