The TCI program was focused on observing hurricanes from the surface to 60,000 feet above the Atlantic, Eastern Pacific, and Gulf of Mexico using a NASA WB-57 aircraft that deployed nearly 800 dropwindsondes with an unprecedented horizontal resolution in four tropical cyclones and obtained high-resolution measurements of the surface winds using HIRAD. Observational highlights detailed dropsonde transects of 2-5 nmi spacing through the inner core of Hurricane Patricia on multiple flights including during the formation, rapid intensification and near-peak-intensity stages. Dropsondes in Patricia, deployed along a 90 nm transect with an unprecedented 2 nm spacing when the storm was at a 175 kt intensity, highlight strong spatial gradients and shear. Likewise, dropwindsondes deployed during Hurricanes Joaquin and Marty reveal strong spatial gradients in winds and thermodynamic properties with a rich spectrum of structure in the horizontal and vertical. Systematic measurements of the hurricane outflow layer made at high-spatial resolution for the first time for a major hurricane will be presented.