A study on filtering aspects of airborne wind energy generators is presented. This class of renewable energy systems aims to convert the aerodynamic forces generated by tethered wings into electricity. The reconstruction of the wing’s position and velocity is investigated here. Different sensor setups are considered, and the related sensor fusion algorithms are presented. The different approaches are compared through experiments on a small-scale prototype. The designed filtering algorithms rely purely on kinematic laws, hence the results obtained are representative also of systems with larger size and different wing designs.