The popularity and utility of DJI Mavics and Phantoms make them great tools for photography, videos and mapping. However, these drones were never designed to capture anything better than inspection-class data. It doesn’t matter if you fly them one at a time or in multi-drone hives, the limitation is inherent to the sensor itself.
Off-the-shelf single-sensor drones have a much lower resolution camera and single wide-field optics, meaning they cannot produce the definition required to produce millimeter precision of the component parts of the structure, mounting frames or tower mounted equipment.
Even when trying to fly closer to the tower, these drones potentially have 50 to 100 times less pixel data available to process than gathered by the Visual Intelligence sensors. And, as these drones fly closer and closer to the tower, risk increases, pilot skill becomes more important, and interference from RF emissions and orbital drift become major factors.
When you look at Mavics and Phantoms through the lens of consistency, reliability or repeatability, these drones don’t come close to providing millimeter accuracy.