TR2 means Payload Furnished Mars Tape Recorder 2 of 2 in NASA
Similar to TR2
ACBM - Active Common Berthing MechanismACC - Aft Cargo Carrier
ACCA - Automatic Cloud Cover Assessment
ACCMS - Advanced Checkout, Control, and Maintenance System
ACCS - Advanced Checkout and Control System
ACE - Advanced Composition Explorer
ACE - Apollo Checkout Equipment
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