The NTSB cited a drone pilot's decision to fly past line of sight, above 400 feet, and into an active TFR as causes and contributors to the September 21 collision between a private DJI Phanton 4 sUAS and a U.S. Army Black Hawk over Hoffman Island in New York Harbor. The helicopter sustained minor damage and landed without incident; the sUAS, operated by Vyacheslav Tantashov, 58, of Brooklyn, was destroyed. Tantashov was identified from registration numbers recovered from the drone's wreckage and cooperated with investigators. The interview required a Russian translator.

The collision occurred at an altitude of 300 feet msl at 7:20 p.m., two minutes before the end of civil twilight. The helicopter was cleared to operate within the TFR. It was over water and not near vessels and therefore was in compliance with FAA regulations and Army guidelines. The helicopter pilot took evasive action but it was too late to avoid the collision.

The Fort Bragg, North Carolina-based helicopter was flying in formation with another Black Hawk as part of the security package for United Nations General Assembly week in New York, an event that attracts high-ranking dignitaries from around the world. It landed safely at Linden, New Jersey after the collision. Observed damage included a dented main rotor blade that required replacement and a damaged window. There were no injuries. The $1,400 Phantom 4 weighs approximately three pounds, has a controlled range of three miles, a maximum speed of 45 mph, and is about one foot square at its widest point.

Investigators documented the sUAS pilot's unsafe operating procedures and near complete lack of knowledge of the FARs. Specifically the pilot flew the aircraft up to 2.5 miles away, “well beyond the line of sight” and “was just referencing the map on his tablet,” unaware of the helicopter's presence. Earlier in the evening, the pilot had flown to an altitude of 547 feet and a distance of 1.8 miles, which was “unlikely to be within the visual line of sight.” During interviews with the NTSB, the pilot said he was aware of “frequent” helicopters in the area, but elected to fly beyond line of sight anyway. “In his interview, the sUAS pilot indicated that he was not concerned with flying beyond visual line of sight, and he expressed only a general cursory awareness of regulations and good operating practices,” the NTSB noted, adding that the sUAS pilot was “unaware of the active TFRs in the area that specifically prohibited both model aircraft and UAS flight.” Recreational drone flights are illegal anywhere in New York except parks.

The sUAS pilot “relied only on the DJI GO4 app for airspace awareness,” according to the Safety Board. While the new DJI GEO app can report TFRs, the NTSB stessed that “this feature is intended for advisory use only, and sUAS pilots are responsible at all times to comply with FAA airspace restrictions. Sole reliance on advisory functions of a non-certified app is not sufficient to ensure that correct airspace information is obtained.” Furthermore, the pilot's tablet did not have a cellular connection, making it unlikely he could have used it to obtain TFR information at flight time.

The NTSB did not find any anomalies with the sUAS “relevant to the flight.”