The US Federal Aviation Administration (FAA) is overstating the threat that drones or unmanned aircraft systems (UAS) actually pose to the aircraft during their flights, according to a study by researchers of Mercatus Center at George Mason University.

Conducted by Eli Dourado and Samuel Hammond from Mercatus Center, the study has taken 25 years of data from FAA’s wildlife strike database.

The researchers have questioned FAA’s latest decision to impose regulation on the operation of UAS, where operators of drones weighing more than 250g are required to register with the agency for a safe national airspace.

"The most serious reported incidents typically involved flocks of large birds."

However, the researchers opine that several drones weighing more than 250g seem to pose miniscule risk to the airspace.

The study stated that although aircraft collide with birds many thousands of times a year, only a tiny fraction of those collisions result in damage to the aircraft, much less human injuries or deaths.

The most serious reported incidents typically involved flocks of large birds.

Since the addition of UAS to the airspace is similar in many respects to an increase in the bird population, the risk to the airspace caused by small drones, weighing up to 2kg, flying in solitary formation is minimal, the researchers opined.

The study also calculated the possibility of airborne wildlife striking an aircraft, using FAA data.

Out of the 160,000 wildlife strikes recorded by FAA since 1990, only 14,314 bird strike incidents have resulted in damage.

There have been only 12 incidents of wildlife strikes that caused injuries or death in more than 25 years, considering that there are around 27,000 commercial aircraft flights a day in the US, the study stated.