unmanned Air vehicle aerial photographic system
Air Leakage Rate of Air Preheater
air to air heat recovery unit
air to air missile launching envelope
arctic air [= arctic air mass]
continental air [= continental air mass]
main air port exhaust air
marine air [= marine air mass
variable air volume (VAV) air conditioning system
variable air volume air conditioning system
conflict of vehicles and non-motorized vehicles
500 kV unmanned substation
anti-radiation unmanned aerial vehicle
Miniature Unmanned Aerial Vehicle
offshore unmanned platform
remote unmanned work system
The Miniature Unmanned Aircraft
UAV Unmanned Aerial Vehicle