Part 107 UAS pilot reported their UAS flew into tree branches during a preprogrammed flight. The UAS was unrecoverable.

Date: 2024-04 · Aircraft: DJI Air 2S · Phase: cruise

Anomalies: inflight-event-encounter-object

Synopsis

Part 107 UAS pilot reported their UAS flew into tree branches during a preprogrammed flight. The UAS was unrecoverable.

Narrative

On or about XA:30 PM on Day 0 I was conducting a flight for the company under Part 107 operations. I was tasked with gathering 'bird's eye view' imagery of the rooftop from 150 feet which I completed successfully. The other task was to capture 'perimeter' images of the roof eaves; which I successfully flew manually with the DJI Fly app. However; I second-guessed myself; and I had created a pre-programmed waypoint flight in the Litchi app to execute a sideways flight; capturing images at predetermined waypoints; in case my images from manual flight were unacceptable to the client. My errors were twofold: the first error was relying on an old satellite mapping image to plan my mission. The tree next to the church that I crashed my drone into had grown since the photographs were taken; and I was unaware of this; so the last waypoint on the mission did not stop short of the tree branches; but instead sent my drone sideways (the only flight direction in which collision avoidance does not work on this model)into the branches. My second error was forgetting that the Litchi app does not have a waypoint override panic mode like the DJI Fly app; where a programmed flight can be stopped by pulling the control sticks inwards and downwards to cause the drone to hover. By the time I remembered that the programmed flight must be stopped by tapping a button on my phone screen; the drone had already collided with the tree branches and become ensnared in the evergreen. The drone was flipped upside-down according to its IMU (Inertial Measurement Unit); and therefore the propellers could not be engaged to cause it to disentangle from the tree. I believed that the drone had fallen on the roof; and I called the church maintenance staff who arrived and looked on the roof using a ladder. They determined that the drone was still entangled with the tree branches and therefore not retrievable. We in fact could not see the drone in the branches; although the footage from the camera was still transmitting and showed a tangle of small twigs with sky beyond. Before the battery drained completely I downloaded the assets I had captured; communicated with the maintenance staff at the church about the event; and filed a claim with DJI for a 'flyaway'/unretrievable drone. The church maintenance staff confirmed that the tree would not need repair or remediation due to the crash; therefore the crash did not cause damages over $500USD. This is why I did not report the incident to the FAA or NTSB. A month later I was contacted by an individual who found the disabled and deactivated drone; and wanted a reward for its return. Not being able to afford a reward for them; I told them to return it to the manufacturer; as it had already been disabled/totaled by DJI. I therefore confirmed that the drone is not in the environment posing any kind of hazard due to its battery or otherwise. I hope that this report will fulfill any reporting obligation that I may be facing; but as far as I can tell from FAA CFR Part 107; I do not have an obligation to report the incident to them due to the low value of the damages incurred (none beyond the UAS itself). Corrective action taken is to reevaluate my mission planning procedure and never rely on satellite imagery for judging the position of foliage or any object that could pose an obstacle to UAS operation. Another corrective action taken is to re-read the manual for the Litchi app to remind myself of the procedure for stopping an automated waypoint flight.

Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.