vertical reference system

attitude-and-heading reference system / attitude and heading reference system (AHRS)

instantaneous vertical speed indicator / instantaneous vertical-speed indicator (IVSI)

grid reference system

guidance reference system

military grid reference system (MGRS)

numbered reference position system

World Geographic Reference System (WGRS); georef

muzzle reference system (MRS)

inertial reference system

strapdown attitude heading reference system

strapdown inertial reference system

attitude-and-heading reference system (AHRS)

heading and attitude reference system

replacement attitude and heading reference system

attitude and heading reference system (AHRS)

world geographic reference system

vertical sliding breech-block system

vertical base system

vertical launching system (VLS)

vertical launch system (VLS)

Mk 41 Vertical Launching System (Mk 41 / Mk 41 VLS)

vertical takeoff and landing tactical unmanned air system

vertical takeoff and landing unmanned aerial system

vertical takeoff unmanned air system

fire extinguishing system sprinkler system and fire alarm system

grid reference box

gyroscopic reference unit (GRU)

lay reference number

map reference

map reference code

NATO Master Cross Reference List (NMCRL) (logistics)

reference