Drone Rules Make Tracking Down Faults a Difficult Feat
Chelsea Scott looks on as Michael Bunds lands a fixed-wing drone in Southern California. Credit: Jui-Chi (Vickie) Lee Source: Drone Rules Make Tracking Down Faults a Difficult Feat - Eos Chelsea Scott and Ramón Arrowsmith, like many earthquake scientists, track down faults. As tectonics researchers at Arizona State University, they need to know where a fault is, how much it’s moved, and how it behaves below the surface. Small uncrewed aerial systems, also known as drones, provide them with high-resolution photographs that capture the necessary information at the scale of centimeters—a higher resolution than some commonly used, easily accessible satellite or airborne data sets. However, collecting drone data along the length of a fault is no simple task. Bigger Is Better A magnitude 7.0 earthquake can produce a 62-mile-long (100-kilometer-long) rupture with surface displacements of up to about 3 feet (1 meter), said Arrowsmith. “You need to have a good enough ruler to measure [that],” he said, which imagery collected from drones can easily provide. The problem, he said, is rapidly covering a 62-mile stretch. Nearly every country that regulates drone operations recommends or requires that pilots maintain visual contact with their drone. One way around the problem is to use a bigger drone. Cheap, heavy quadcopters—helicopters that can easily take off and land—are small compared with lightweight, expensive fixed-wing drones that look like tiny airplanes. In February 2020, Scott and three colleagues spent almost 4 days mapping 25 miles (40 kilometers) of the San Andreas Fault in Southern California. Although they had quadcopters, Scott said “the workhorse was the fixed-wing drone.” “Because fixed-wing drones are so expensive, flight planning is done very, very carefully, and unfortunately the project is over if the drone crashes.” The average quadcopter can be spotted approximately half a mile (0.8 kilometer) away; mapping long linear features like [...]