Atmospheric trace constituents in the upper troposphere and lower stratosphere are now being measured as part of the NASA Global Atmospheric Sampling Program (GASP), using fully automated air sampling systems on board commercial 747 aircraft in routine airline service. Measurements of ozone mixing ratio and related meteorological information obtained during several GASP flights in March, 1975 are reported. The height of the tropopause during these flights was obtained from National Meteorological Center (NMC) gridded data. Good agreement is observed between the tropopause heights and the GASP ozone, wind, and static air temperature data. The data presented show examples of upper tropospheric and lower stratospheric ozone mixing ratio variations, both as a functions of geographical location and aircraft altitude.