– Even small toy drones can pose a significant hazard to traditional planes and helicopters in a collision, according to a study.

Drones will “most certainly” cause more damage to aircraft than birds, which have caused airliners to crash, according to the study by Aero Kinetics Aviation of Fort Worth, Texas. Drones are made of solid plastics, batteries and metal, which cause greater damage in a collision compared to bird flesh, the study found.

“A head-on drone strike into the inlet of a turbine engine on a commercial airliner on approach or departure would cause severe damage to the engine and potentially a catastrophic failure,” the company said in the study.

The Federal Aviation Administration is studying the damage that a drone would cause in an impact but hasn’t released any findings. The FAA, which is drafting regulations to manage the rapid growth of civilian drones, has recorded more than 100 reports a month this year of pilot encounters with drones, a sharp increase over last year. Some of the incidents were close calls with airliners.

So far there haven’t been any of the kind of tests on drones that aircraft and engine manufacturers must perform to ensure their products can safely withstand collisions with birds. For example, the FAA requires that birds of various sizes are flung into jet engines to prove an impact in flight won’t cause too much damage.

Aero Kinetics’ Chief Executive W. Hulsey Smith said in an interview that the company wanted to use mathematical models to predict what would happen in drone collisions. The company is looking for partners to help it perform actual impact tests, he said.

“We need to conduct additional testing to fully understand the risk that toy drones pose to manned aircraft,” Smith said. “We also need to have a comprehensive public education program so the public understands how dangerous toy drones are to aircraft.”

Using weights of actual consumer drones and the speeds they are capable of flying, the company was able to estimate how various parts of an aircraft would withstand impacts. The analysis was based on common models sold by SZ DJI Technology Co. Ltd., the world’s largest commercial drone manufacturer.

An airliner windshield would be capable of withstanding impacts with drones during lower altitude maneuvers approaching or departing from airports, the report concluded.

Last year there were 13,668 cases of aircraft striking birds and other wildlife, according to an FAA report. The impacts destroyed 67 aircraft, most of them privately owned smaller planes, the report said.