XPOP means X-axis Perpendicular to Orbital Plane in
NASA
Similar to XPOP
AA - Astronomical Applications
AA - Adverse Action
AA - Antenna Assembly
AAA - Avionics Air Assembly
AAC - Aft Access Closure
AACB - Aeronautics and Astronautics Coordinating Board
AAD - Attitude Anomaly Detector
View all in NASA