AAIB record shows a DJI Matrice 4E hit a tower crane with obstacle avoidance switched on

A DJI Matrice 4E surveying drone flew into the top of a tower crane at a building site in Cheetham Hill, Greater Manchester, on 3 August 2026, although its obstacle avoidance was switched on, according to the latest record of drone occurrences from the UK Air Accidents Investigation Branch (AAIB). It then fell about 120 metres to the ground.

The drone was flying a pre-selected survey route over the site. According to the construction company's internal investigation, the firm and its pilots may not have fully understood the limits of the software that avoids obstacles.

The AAIB classed it as a Record Only case, so there was no full independent investigation, and the published details come mostly from the incident report and the parties involved.