The first of these products was granted U.S. Patent 6,970,104 on 29 Nov., 2005. Designed to augment the cockpit display of traffic information (CDTI), 4CAS--4-Dimensional Collision-Avoidance System--is currently in the proof-of-concept stage. Shown below in prototype, 4CAS goes far beyond TCAS, and is designed to enable manual free flight in modern commercial and general aviation aircraft flightdecks.