The Aircraft Reply and Interference Environment Simulator (ARIES) makes possible the performance assessment of a Discrete Address Beacon System (DABS) sensor under its specified maximum aircraft load. To do this ARIES operates upon a taped traffic model to generate simulated aircraft replies and fruit, feeding them to the sensor at RF. Support documentation for ARIES, of which this is the second volume, consists of: Volume 1: Principles of Operation Volume 2: Appendices to the Principles of Operation Volume 3: Programmer's Manual The Appendices to the Principles of Operation is comprised of a set of technical articles providing (a) explanations of design and programming aspects of the ARIES system not covered in the main volume, (b) detailed data format and data structure definitions, (c) detailed explanations of the meaning of ARIES error messages, and (d) an analysis of certain effects to be expected when more than one ARIES simulator are interconnected.