Recovery of UAVs

Abstract

Recovery of an unmanned aerial vehicle (UAV) may utilize a remote‐controlled or automated landing on a runway, sometimes using arresting gear to limit the landing run‐out, or an automated arrested landing on an aircraft carrier. Small UAVs can be flown into the ground at a low rate of decent and allowed to slide to a stop. For mid‐air recovery, the UAV deploys a parachute or parfoil and a large manned aircraft snags the parachute/parafoil with a hook and winches in the UAV. So‐called “zero‐length recovery” is accomplished by flying a fixed‐wing UAV into a vertical net. UAVs capable of vertical landing can be landed under remote manual or automated control on any reasonably level surface. Shipboard recovery has been implemented with vertical nets and with a combination of a parafoil and snagging by the ship followed by winching the UAV down to a landing pad, with many special requirements to deal with the possibility that the landing pad on the ship may be moving rapidly in an irregular manner, including violent pitch and roll motion. Each of these approaches has different requirements and some, such as vertical nets, impose significant restrictions on the basic configuration of the air vehicle.