The paper discusses the preliminary analysis of an urban availability tool required for preflight flight planning. In this tool, areas in an urban environment are assessed with respect to GNSS availability, separation to traffic and obstacles, impact of UAS noise, and various other criteria. GNSS availability will drive the necessity to include alternative navigation sensors such as laser scanners, vision sensors and altimeters in the navigation mechanization to meet the required navigation performance necessary for urban operations. This paper shows the initial results of the GNSS availability tool and discusses the sensor integration strategy when GNSS-only availability is not sufficient.

This paper discusses the flight test setup and preliminary results of a precise relative navigation and separation assurance system to support safe simultaneous operation of general aviation aircraft and UAS at low altitudes in the vicinity of an uncontrolled airfield. With an increased use of UAS for a wide variety of applications, such as law enforcement, search and rescue, agriculture, infrastructure inspection, maintenance, mapping, filming and journalism, it is expected that UAS will be taking off, landing or otherwise operating at airfields at the same time as manned aircraft. In that case, it will be required that the UAS not only has precise knowledge of its location and velocity to enable an automatic flight at lower altitudes with sufficient accuracy, integrity, availability and continuity to support its operation (e.g. takeoff , landing, flight patterns), but also to support broadcasting its position and velocity to the other aircraft in the vicinity, for improved awareness of the UAS location and to achieve separation assurance