We report on our recent 3D numerical models of the launching of hot, high-speed jets in a coronal hole following the emergence of magnetized plasma from the solar interior. As part of the same research, we have also analyzed Hinode (EIS and XRT) and Soho-MDI observational data of an actual process of flux emergence followed by jet launching in a coronal hole. From the observations, we reconstruct the magnetic topology at the emergence site and calculate velocity and further physical properties of the observed event. The 3D model was calculated for realistic conditions in a coronal hole, including, in particular, a low-density (108 particles cm-3), high Alfven speed plasma prior to the emergence. After emergence, a ribbon-like current sheet is created at the site of collision of the emerging and preexisting magnetic systems. Field line reconnection ensues, which leads to the ejection of the X-Ray jet. We analyze the global magnetic topology, and the temperature, velocity and current distribution in the 3D experiment. The numerical results provide a good match to the observed features of the coronal hole jets. This is meant regarding both our own observational results as well as the ranges and average values of the statistical study by Savcheva et al. (2007).