What Really Happens if a Drone Lands on Your Head?

A consortium of research organizations published a report last week describing what might really happen if a drone hit a person on the ground.

The report was commissioned by the FAA to help inform future regulation about drone flight over people, currently restricted.  The prohibition of flight over people limits many commercial applications such as drone delivery in urban environments.

The Alliance for System Safety of UAS through Research Excellence (ASSURE) began the research in September 2015.  After researching toy standards, drone features, and construction the team
“conducted crash tests, dynamic modeling, and analyses related to kinetic energy, energy transfer, and crash dynamics,” says the FAA.

Representatives from NASA, DOD, and FAA reviewed the findings.  Findings describe 3 types of injury which small drones might cause: blunt force trauma (most significant), lacerations, and penetration injuries.  Researchers recommend that regulators develop a simple test method to evaluate a drone’s potential for injury.

The full report summary concludes that: “The crash test results and subsequent analysis strongly suggest that RCC-based thresholds are overly conservative because they do not accurately represent the collision dynamics of elastically-deformable sUAS…” leading major drone manufacturer DJI to welcome the report as further corroboration of drone safety.  DJI says the report established that “small unmanned aircraft systems (UAS) are far more safe to operate around people than earlier models had assumed.”

“ASSURE concluded that a DJI Phantom 3 drone falling on a person’s head has a 0.03% chance or less of causing a head injury, compared to a 99% risk of head injury from blocks of steel or wood with the same weight,” says DJI. “While other materials transfer their force to a person’s head in a collision, a DJI Phantom 3 drone absorbs much of the energy – resulting in much less energy being transferred.”

“ASSURE’s report is the first thorough scientific study of the risk drones pose to people on the ground, and we are pleased that it validates our own findings that earlier measurement standards grossly overstate the risks of injury from a drone,” said Brendan Schulman, DJI Vice President of Policy and Legal Affairs.

DJI and other manufacturers provided the research team with materials and resources for the tests.  Manufacturers have struggled to convince regulators that conclusions based on outdated technology and computer algorithms lead to overly restrictive regulations, and limit the commercial drone industry.

DJI published their own report earlier this year concerning drone risk, saying that “the 250 gram standard was based on poorly chosen data and deeply flawed assumptions,” and shouldn’t be used as a basis for regulation.  Recreational and prosumer drone companies have lobbied FAA for a micro drone classification, reducing regulations on drones weighing less than 2.2 kg.  While the micro drone classification has been included in earlier versions of the FAA Reauthorization package, FAA indicates that it will not implement size-based categories for regulation.