This data set unites the individual data of the Airborne measurements of radiative and turbulent FLUXes of energy and momentum in the Arctic boundary layer (AFLUX) campaign, carried out in spring northwest of Svalbard (Norway). The objective of AFLUX was to study turbulent fluxes of energy and momentum in the Arctic boundary layer and low- and mid-level mixed-phase clouds and their role in Arctic amplification. The research aircraft Polar 5 was equipped with active and passive remote sensing instruments, measurements for turbulent and radiative energy fluxes, insitu probes for cloud and aerosol particles, and dropsondes. In total, 14 research flights with 67 flight hours over the open ocean and the marginal sea ice zone have been performed between 19 March and 11 April 2019.