What happened
On October 1, 2025, at approximately 09:49 mountain standard time, two unmanned aircraft systems (UAS) were involved in a collision with a mobile crane near Tolleson, Arizona. The aircraft, an MK30 with registration N579PA, was operating as a Part 135 non-scheduled cargo flight.
A Link Belt ATC-3275 mobile crane, equipped with a 67 ft bi-folding lattice fly, had been erected at a jobsite earlier that morning. The crane operator reported feeling an impact from a UAS at 09:49. While the operator was evaluating the first strike, a second UAS impacted the stationary crane. The crane was at an estimated height of 197.3 ft above ground level (agl) at an angle of 25 degrees when the impacts occurred. The impact heights for the drones were estimated to be between 150 and 165 ft agl.
Flight track data for the aircraft showed that the UAS activated at 09:24:40 and performed flight checks. After departing a package delivery center on a northern heading, the aircraft turned east. The data recording ceased at 09:49:03 at an altitude of approximately 1,218 ft mean sea level (msl), which was about 200 ft agl, roughly 150 ft west of the crane's location.
There were no injuries resulting from the incident. The collision caused substantial damage to the aircraft.
The investigation
First responders arrived at the scene to find that the collision of the two UAS units with the crane had caused a battery fire. Upon examination of the accident site, the UAS was found on the ground near the crane with damage to the fuselage and wings. The UAS battery had ejected from the aircraft and ignited.
An inspection of the Link Belt ATC-3275 crane structure revealed no structural damage, though paint transfer from the UAS was noted. The operator noted that ground surveillance crews had performed rooftop scans of the area earlier that morning at 06:58 and had not identified any obstructions.