A&L: Approach and Landing
A&P: Attitude and Pointing
AAA: Astronaut-Actuated Abort
AACCS: analytical approach to candidate constellation selection
AACS: Attitude and Antenna Control System
AACS: Attitude and Articulation Control Subsystem
AAFE: Advanced Applications Flight Equipment
AAIR: Advanced Atmospheric sounder and Imaging Radiometer
AAO: Astronaut Activities Office
ABE: Air-Based Electronics
ABM: Apogee Boost Motor
ACA: Altitude Controller Assembly
ACA: Attitude Controller Assembly
ACDNS: Attitude Control, Determination & Navigation
ACDS: Attitude Control and Determination System
ACE: Attitude Control Electronics
ACEU: AeroControl Electronics Unit
ACME: Attitude Control and Maneuvering Electronics
ACP: Astronaut Control Panel
ACPM: Attitude Control Propulsion Motor
ACPS: Attitude Control Propulsion System
ACS: Aft Crew Station
ACS: Altitude Control and Stabilization
ACS: Attitude Control and Stabilization
ACS: Attitude Control System
ACTS: Advanced Communication Technology Satellite
ACTS: Advanced Communications Technology Satellite
ADAC: Attitude Determination And Control
ADACS: attitude determination and control system
ADC: Aerospace Defense Command
ADC: Attitude Determination & Control
ADCN: Attitude Determination, Control & Navigation
ADEOS: Advanced Earth Observing Satellite
ADFRF: Ames/Dryden Flight Research Facility
ADFRF: Ames-Dryden Flight Research Facility
ADI: Attitude Direction Indicator
ADL: Avionics Development Laboratory
ADS: Attitude Determination Subsystem
ADS: Attitude Display System
AE&AT: Aircraft Engineering & Aerospace Technology