Science advisers to the federal government say safety regulators are hindering the spread of commercial drones by being too cautious about the risks posed by the flying machines.
The National Academies of Science, Engineering and Medicine said in a report Monday that federal safety regulators need to balance the overall benefits of drones instead of treating them the same way that they oversee airliners.
Academy experts said in a strongly worded report that the Federal Aviation Administration tilts against proposals for commercial uses of unmanned aircraft without considering their potential to reduce other risks and save lives.
For example, they said, when drones are used to inspect cell-phone towers, it reduces the risk of making workers climb up the towers.
The study on the FAA's work on integrating drones into the nation's airspace was requested by Congress last year.
In a statement, an FAA spokesman said the agency was working to safely speed the integration of drones into the airspace. The science board's recommendations match the FAA's efforts "and we see them as an endorsement of our efforts and encouragement to accelerate our efforts," he said.
The drone industry hailed the report. The president of the Association for Unmanned Vehicle Systems International, a trade group, called for a "flexible" approach to regulation including allowing operators to fly drones beyond their line of sight, at higher altitudes and weights greater than 55 pounds.
Others including airline pilots have expressed concern about more drones sharing the airspace. The FAA is investigating an incident reported in February in which a drone flew close to a Frontier Airlines jet approaching Las Vegas. A drone hit a small charter plane in Canada last October, and other operators have been charged with interfering with firefighting planes.
In Monday's report, the science academies leaned on a 14-member committee whose members come mostly from universities and research groups but also the aerospace industry, including a representative of Boeing's drone business.
The high-level science board said that the FAA was making "overly conservative risk assessments" about drones by applying the same near-zero tolerance for risk that it uses with other aircraft.
"In many cases, the focus has been on 'What might go wrong?' instead of a holistic risk picture" that considers overall risk and benefit, the advisers wrote.
Instead, the advisers recommended, the FAA should meet requests for drone operations approvals by saying, "How can we approve this?"
The board was critical of FAA culture even while acknowledging that the FAA's approach has helped make manned aviation safer.
"The committee concluded that 'fear of making a mistake' drives a risk culture at the FAA that is too often overly conservative, particularly with regard to (drone) technologies, which do not pose a direct threat to human life in the same way as technologies used in manned aircraft," the board experts wrote.
They said that FAA staffers may believe they could endanger their careers by allowing any new risk.
The board said its committee recommended that the FAA be guided by asking whether it can make drone use as safe as other background risks in everyday life.
"We do not ground airplanes because birds fly in the airspace, although we know birds can and do bring down aircraft," they wrote.