Field Report: Integration of a Parachute Rescue System into an Existing Unmanned Aerial Vehicle

In many parts of the world, such as Europe, the operation of drones requires the approval of a competent authority if the intended operation could pose a risk to third parties. The possible risks are determined, for example, by the size of the drone, whether the operation is planned in the vicinity of people or beyond the line of sight of a pilot. The permit may, among others, be achieved with the SORA process, that is proposed by JARUS and accepted by EASA as acceptable means of compliance. During this process, the risks of operation are determined and the requirements that the operator must fulfill in order to fly the drone are assessed. The risks in the air and on the ground as well as possible remedial measures specific to this operation are examined and compared. A possible mitigation to reduce the estimated ground risk is a reduction of the effects in case the drone impacts the ground. One way to implement this mitigation is to integrate a parachute in the drone and show that the parachute is applicable to cover all failure cases of the drone and reduces the impact energy in a case of crash. This paper presents a way how we developed, tested and integrated a parachute rescue system in an already existing research drone prototype which only exists once. Therefore, tests to evaluate the parachute and its functionality which are likely to destroy the drone were not possible. An applicable parachute system was not available, so one was developed and evaluated in representative airflow exposition on a driving testbed and laboratory tests. Finally, we will give some advice that we have learned during this work and that may also help other working groups if they are also planning a drone mission with a parachute rescue system.