mbers 4066010-901. -902. and .903. and replace those units with new units that incorporate updated CoMskin avoidance system ICAS) logic, kleuttiled es Version 6.O4A in Mitre letter FO46-1.4O69.id dated September 21. 1993. • • L21 Modify the computersuricIllance {ogle on Honeywell TCAS II computer units, • 1