Study Finds Drones Pose Much Greater Threat Than Birds to Aircraft

As part of a multi-institution Federal Aviation Administration (FAA) study focused on unmanned aerial systems, researchers at The Ohio State University are helping quantify the dangers associated with drones sharing airspace with planes.

Last week, a research team from the Alliance for System Safety of UAS through Research Excellence (ASSURE) released a report concluding that drone collisions with large manned aircraft can cause more structural damage than birds of the same weight for a given impact speed.

The FAA will use the research results to help develop operational and collision risk mitigation requirements for drones. ASSURE conducted its research with two different types of drones on two types of aircraft through computer modeling and physical validation testing.

Reports of close calls between drones and airliners have surged. The FAA gets more than 100 sightings a month of drones posing potential risks to planes, such as operating too close to airports. The FAA estimates that 2.3 million drones will be bought for recreational use this year, and the number is expected to rise in coming years.

Unlike the soft mass and tissue of birds, drones typically are made of more rigid materials. The testing showed that the stiffest components of the drone—such as the motor, battery and payload—can cause the most damage to the aircraft body and engine.

The researchers concluded that drone manufacturers should adopt “detect and avoid” or “geo-fencing” capabilities to reduce the probability of collisions with other aircraft.

Science From Above

About 5,000 meters high in the Peruvian Andes, scientists are mapping glaciers and wetlands in the Cordillera Blanca mountain range with 10-centimeter precision to gauge how climate change will affect the half-million local residents who rely in part on those glaciers for their water supply.

Their strategy provides a template for research teams that are investigating water security in other areas of the world with much larger populations, including China and India.

The groundwater system would have been very hard to obtain without special high-altitude unmanned aerial vehicles (UAVs) that Wigmore designed and built, and time-lapse thermal camera systems that colleague Jeffrey McKenzie at McGill University developed.

In the Cordillera Blanca, clouds block satellite views for all but a few weeks a year, and the terrain is too irregular to take reliable ice surface measurements by hand. Traditionally, scientists’ only other option would be to fly remote sensing equipment over the ice in an airplane – an endeavor that is not only expensive, but dangerous given the mountains’ sharp changes in elevation.

The Ohio State UAVs have a 10-centimeter resolution, work despite frequently cloudy conditions in the mountains of Peru and cost a few thousand dollars each. In contrast, satellites provide a half-meter resolution at best, work only during the two months a year when the region is relatively cloud-free and cost millions of dollars.

Whereas airplane surveys cost hundreds of thousands of dollars, and satellites cost millions, he can build a UAV for around $4,000.

Wigmore described the Llaca Glacier’s ice loss and collapse of the calving front as more dramatic than he would have expected.

Wigmore also presented measurements that suggest a key glacier in the region’s Llaca Valley is changing rapidly. He recorded an average of 0.7 meters of thinning in one year, with a maximum of 18 meters of loss in some locations. For example, an ice cliff at the leading edge of the glacier collapsed over a two-week period early in 2015.