Big-C	Barometric to Geometric Converter
GNSS	Multidisciplinary Digital Publishing Institute
ECMWF	Directory of open access journals
NWM	Numerical Weather Model
ERA	ECMWF re-analysis
ATC	Air Traffic Control
ATM	Air Traffic Management
VNAV	Vertical Navigation
ICAO	International Civil Aviation Organization
ISA	International Standard Atmosphere
PBN	Performance Based Navigation
MSL	Mean-Sea Level
HALO	High Altitude and Long Range Research Aircraft
OMO	Oxidation Mechanism Observation
DLR	German Aerospace Center
BAHAMAS	Basic HALO Measurement and Sensor System
VPPL	Vertical Path Performance Limit
FMS	Flight Management System
LDACS	L-Band Digital Aeronautical and Communication Systems
DME	Distance Measuring Equipment
VOR	VHF Omni-Directional Radar
UAM	Urban Air Mobility
UAS	Unmanned Aerial System