The National Transportation Safety Board is investigating the Sept. 21 collision of a civilian drone and a U.S. Army UH-60 helicopter east of Staten Island, New York, as concerns mount over the rising number of unmanned aircraft in U.S. airspace.
The safety board said on Thursday that the helicopter had landed safely, but its main rotor blade, window frame and transmission deck were damaged. The Army is conducting a mishap investigation, the agency said.
The NTSB said it had recovered a motor and arm from the DJI Phantom 4 drone from the helicopter, identified and interviewed the drone operator and reviewed data logs for the flight.
China-based DJI said it was assisting the agency.
“DJI is firmly committed to the safety of our products,” the company said. “We have always instructed drone operators to obey the laws and regulations applicable to drones in their jurisdiction.”
Government and private-sector officials have become concerned that dangerous or even hostile drones could get too close to places like military bases, airports and sports stadiums.
Earlier this year, the U.S. Federal Aviation Administration banned drone flights over 133 U.S. military facilities. In August, the Pentagon said U.S. military bases could shoot down private and commercial drones that could endanger aviation safety or pose other threats.
Also on Thursday, the FAA began banning drone flights over 10 U.S. landmarks, including the Statue of Liberty in New York and Mount Rushmore National Memorial in South Dakota, at the request of national security and law enforcement agencies.
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The FAA and U.S. Interior Department are also barring drone flights up to 400 feet (122 m) within the boundaries of sites including the USS Constitution in Boston, the Gateway Arch in St. Louis and the Independence National Historical Park in Philadelphia. The list also includes Folsom Dam and Shasta Dam in California, Glen Canyon Dam in Arizona, Hoover Dam in Nevada and Grand Coulee Dam in Washington state.
The flight restrictions were announced last week.
The Trump administration said in June that it wanted to promote the development and commercialization of drones.
The Obama administration implemented rules opening the skies to small drones for education, research and routine commercial use. The Trump administration is considering allowing expanded drone use for purposes such as deliveries, where aircraft would fly beyond the sight of an operator.