To achieve Net Zero, we require a complete understanding of the climate impacts of Near-Term Climate Forcers (NTCFs). Aviation NOx emissions (ANE) represent a major uncertainty in aviation's NTCF climate impacts. Using new in situ constraints of observations of NOx, a series of state-of-the-art coupled chemistry-climate models, state-of-science emission inventories and by developing a range of new possible future emission scenarios we will constrain and reduce this uncertainty in REVEAL-NOx. In doing so we will address Themes 1.2, 2.1 and 2.2 of the Jet Zero call, enabling solutions for a reduction in aviation's non-CO2 climate impacts to be delivered through a better understanding of the need for any trade-offs. It is unlikely that we will get to zero NOx emissions from aviation, so it is paramount we fully constrain ANE radiative impacts in order to successfully deliver Net Zero aviation emissions.