Techniques involve releasing and/or capturing a fixed-wing aircraft using an aerial vehicle with VTOL capabilities while the fixed-wing aircraft is in flight. For example, the VTOL aerial vehicle may take off vertically while carrying the fixed-wing aircraft and then fly horizontally before releasing the fixed-wing aircraft. Upon release, the fixed-wing aircraft flies independently to perform a mission (e.g., surveillance, payload delivery, combinations thereof, etc.). After the fixed-wing aircraft has completed its mission, the VTOL aerial vehicle may capture the fixed-wing aircraft while both are in flight, and then land together vertically. Such operation enables the fixed-wing aircraft to vertically take off and/or land while avoiding certain drawbacks associated with a conventional VTOL kit such as being burdened by weight and drag from the VTOL kit's rotors/propellers, mounting hardware, etc. during a mission which otherwise would limit the fixed-wing aircraft's maximum airspeed, ceiling, payload capacity, endurance, and so on.

The present disclosure describes systems and methods for escorting small unmanned aircraft (herein drones). An escorting drone approaches the escorted drone and transmits to it an escort signal. In an embodiment, the escort signal is a GNSS signal fashioned to be the same as the GNSS signal that would be received by the escorted drone, other than being slightly stronger in signal strength and having slightly altered component delays. In another embodiment, the escort signal is a radio frequency control channel signal. Escorting may be utilized to guide a drone from a preprogrammed point to a docking zone in a droneport; to guide a drone though an urban canyon or inside a building where GNSS signals are not reliably received; to retrieve a drone with which communications has been lost; or to escort a drone to safety out of a no-flight zone such as around an airport.

The present disclosure describes systems and methods for escorting small unmanned aircraft (herein drones). An escorting drone approaches the escorted drone and transmits to it an escort signal. In an embodiment, the escort signal is a GNSS signal fashioned to be the same as the GNSS signal that would be received by the escorted drone, other than being slightly stronger in signal strength and having slightly altered component delays. In another embodiment, the escort signal is a radio frequency control channel signal. Escorting may be utilized to guide a drone from a preprogrammed point to a docking zone in a droneport; to guide a drone though an urban canyon or inside a building where GNSS signals are not reliably received; to retrieve a drone with which communications has been lost; or to escort a drone to safety out of a no-flight zone such as around an airport.

Systems and methods for use in navigating aircraft are provided. The systems can use Geometry Redundant Almost Fixed Solutions (GRAFS) or Geometry Extra Redundant Almost Fixed Solutions (GERAFS) to compute high confidence error bounds for a heading angle estimate or pitch angle derived using signals received on at least two antennas.

The present disclosure relates to a technical field for airborne navigation and discloses a data acquisition system and method for airborne navigation devices based on unmanned aerial vehicle. The system includes an unmanned aerial vehicle flight control system, a navigation devices test antenna array, a multi-channel signal processing module, a signal acquisition module, an ADS-B transmitting module, a GNSS receiver, a UHF data link receiver, a power module and a ground station. The unmanned aerial vehicle is equipped with corresponding modules to receive signals from ground navigation devices, perform corresponding processing and storage, and transmit data to the ground, at the same time, receive control instructions sent by the ground to complete corresponding monitoring, analysis and inspection.

The present disclosure relates to a technical field for airborne navigation and discloses a data acquisition system and method for airborne navigation devices based on unmanned aerial vehicle. The system includes an unmanned aerial vehicle flight control system, a navigation devices test antenna array, a multi-channel signal processing module, a signal acquisition module, an ADS-B transmitting module, a GNSS receiver, a UHF data link receiver, a power module and a ground station. The unmanned aerial vehicle is equipped with corresponding modules to receive signals from ground navigation devices, perform corresponding processing and storage, and transmit data to the ground, at the same time, receive control instructions sent by the ground to complete corresponding monitoring, analysis and inspection.

A relative navigation system comprising of a pair of Global Navigation Satellite System (GNSS) and Inertial Navigation System (INS) units that communicate to provide updated position, velocity and attitude information from a master to a rover. The rover unit produces a carrier based solution that enables the system to reduce the uncorrelated low latency position error between the master and the rover units to less than 50 cm.

A relative navigation system comprising of a pair of Global Navigation Satellite System (GNSS) and Inertial Navigation System (INS) units that communicate to provide updated position, velocity and attitude information from a master to a rover. The rover unit produces a carrier based solution that enables the system to reduce the uncorrelated low latency position error between the master and the rover units to less than 50 cm.

A method of aligning an aircraft with a landing platform in motion comprises measuring a GPS heading with at least one GPS sensor positioned at a known location relative to the landing platform while the landing platform is in motion, measuring an orientation of the aircraft with an orientation sensor fixed relative to the aircraft, calculating an orientation of the landing platform from the GPS heading, calculating an orientation offset between the measured orientation of the aircraft and the calculated orientation of the landing platform, and changing an orientation of the aircraft or the landing platform to reduce the orientation offset. A system for landing and securing an aircraft in an enclosure, a system for disconnecting a tether from an aircraft, and a system for landing an aircraft in an enclosure are also described.

Systems and methods include UAVs that serve to assist carrier personnel by reducing the physical demands of the transportation and delivery process. A UAV generally includes a UAV chassis including an upper portion, a plurality of propulsion members configured to provide lift to the UAV chassis, and a parcel carrier configured for being selectively coupled to and removed from the UAV chassis. UAV support mechanisms are utilized to load and unload parcel carriers to the UAV chassis, and the UAV lands on and takes off from the UAV support mechanism to deliver parcels to a serviceable point. The UAV includes computing entities that interface with different systems and computing entities to send and receive various types of information.