Advanced Technology Program 
Acceptance Test Procedure 
Ammunition Transfer Point 
Advanced Tracking Prototype 
AppleTalk Transaction Protocol 
Acceptance Test Plan 
Aeronautics Test Program 
Accelerated Training Program 
adenosine triphosphate 
Adult Treatment Panel 
Airline Transport Pilot 
All Tests Pass 
Allied Tactical Publication 
Allied Technical Publication 
Application Transaction Program 
Authority to Proceed 
Automatic Train Protection 
Absolute Time Processor 
Acceptace Test Procedure 
Acquisition Tracking and Pointing 
Activation Test Program 
Additional Training Period 
Additional Training Periods 
Advance Technology Program 
Advanced Technology Panel 
Advanced Technology Provider 
Air Travel Plan 
ALPS Tunneling Protocol 
Alternate Turbopump Production 
Army Training Program