Terrain Awareness and Warning System (TAWS)ý Analog addresses the need for standard TAWS installations in older aircraft that have analog equipment interfaces. The analog unit is intended as a replacement for ARINC Characteristic 594: Ground Proximity Warning System (GPWS) equipment. The document is intended to compliment ARINC Characteristic 762: Terrain Awareness and Warning System (TAWS) for later model aircraft having digital equipment interfaces.