All-to-All Scatter 
Ascii Adjust for Subtraction 
Abbreviated Address Signal 
Abort Advisory System 
Adaptive Antenna System 
Aeronautical Advisory Station 
Agencywide Administrative Systems 
Attack Assessment System 
Authorized Application Specialist 
Accrediting Authorities 
Acquisition Activities 
Action Authorization Sheet 
Active Applications 
Adaptive Antenna Systems 
ADVANCED ADMINISTRATION SYSTEM 
Advanced Antenna System 
Airlock Attach System 
American Astronautics Society 
Anfahrassistent 
Apollo Abort System 
Association of Asian Studies 
Australian Acoustical Society 
Auto Adjusting Suspension 
Auto Area Segmentation 
Automatic Archival System