History of Flight
On October 21, 2020, about 1612 eastern daylight time, a Bell 206B helicopter, registration N716VL, was substantially damaged during an accident near Point Lookout, New York. The pilot, who was the sole occupant, sustained minor injuries. The flight was operated under 14 Code of Federal Regulations Part 91 as a personal flight.
The pilot initially departed Republic Airport (FRG) in Farmingdale, New York, for Sterling Heliport (PS01) in Croydon, Pennsylvania, for scheduled maintenance. According to automatic dependent surveillance-broadcast (ADS-B) data, the helicopter returned to FRG about 12 minutes after takeoff. The pilot reported waiting on the ramp for adverse weather to improve and later decided to depart again after being informed of another pilot's report of visual flight rules (VFR) conditions at about 800 ft. At 1544:03, that pilot reported to air traffic control that a "nice thin little [cloud] layer" existed between 800 and 1,000 ft.
The helicopter departed again around 1546 under a special VFR clearance and flew south-southwest. The pilot soon contacted John F. Kennedy International Airport (JFK) air traffic control and was advised that the ceiling was at 300 ft, with instructions to remain at or below 500 ft. The pilot later stated he did not expect that ceiling and that the weather was "coming in quick and hard."
At 1558:26, while about 12 miles southwest of FRG, the pilot advised the controller he would return to the airport. The controller cleared the helicopter to turn and maintain an altitude at or below 1,400 ft, which the pilot acknowledged. The pilot said he programmed a direct route to FRG into the helicopter's electronic flight instrument system and a tablet computer, then attempted to turn to a north-northeast heading, but the helicopter began to yaw. ADS-B data showed two left 180° turns. At 1600:40, the pilot told the controller, "we're in fog we're trying to get down below to get back to Farmingdale."
The helicopter briefly flew northeast, then turned left to a northerly heading and subsequently made a 180° right turn to the southeast. At 1603:10, the controller asked if the helicopter was instrument flight rules (IFR) capable, and the pilot replied, "I am…the ship isn't." The flight continued southeast. Over Point Lookout around 1604, the helicopter turned right 180°, flew north, then east, and then made approximately seven 360° right turns. At 1611:13, the controller declared an emergency on the pilot's behalf, informed him of a pilot report indicating VFR conditions at 1,000 ft, cleared him to climb, and provided the latest altimeter setting. The pilot did not respond.
ADS-B data showed a 360° right turn followed by a 180° right turn, then a northerly heading and a left turn. At 1611:38, an unidentified pilot exclaimed "whoa" multiple times. The controller attempted to contact the accident pilot but received no reply. The straight-line distance between the third-to-last and second-to-last ADS-B targets (at 1611:35 and 1611:39) was about 148 ft, corresponding to an average groundspeed of about 22 knots. The accident site was located about 250 ft at 052° from the last ADS-B return.
The pilot reported that the flight entered instrument meteorological conditions while flying south. He described the conditions as "soup that thick" and said he heard a loud noise from the tail, after which the helicopter yawed rapidly clockwise. Antitorque control pedal input did not correct the yaw. The pilot said he lowered the collective and thought it lowered once the yaw began. He did not recall any alarms or a low rotor rpm warning and believed a mechanical failure of the tail rotor had occurred.
Meteorological Information
The pilot obtained weather information after arriving at FRG around 1200, using the Foreflight application. At 1304, the National Weather Service (NWS) Aviation Weather Center issued an AIRMET advisory for IFR conditions covering the accident location at the accident time.
At 1537, a terminal aerodrome forecast for JFK indicated wind from 160° at 9 knots, visibility of 5 statute miles, mist, and broken clouds at 400 ft and 1,200 ft above ground level (agl). The forecast also indicated temporary conditions between 1600 and 2000 with visibility greater than 6 statute miles, no significant weather, scattered clouds at 700 ft and 1,500 ft agl, and a ceiling broken at 3,500 ft agl.
The JFK automated surface observing system (ASOS) provided an hourly observation at 1551. A 5-minute observation at 1610 showed visibility of 0.5 statute mile, mist, and a broken ceiling at 300 ft agl, with surface visibility of 1.5 statute miles. About 34 minutes after the accident, at 1646, a pilot reported cloud bases at 200 ft and cloud tops at 500 ft over JFK.
Wreckage and Impact Information
Postaccident examination revealed that the aft portion of the tailboom, including the tail rotor assembly and vertical fin, had separated about 1.5 ft forward of the tail rotor gearbox mount. The fracture location coincided with the main rotor blade tip path. Both tail rotor blades remained attached to the hub; one was minimally damaged, and the other was heavily distorted. The forward fuselage sustained heavy impact damage, and the center box structure containing flight controls was crushed and distorted. The pilot's seat and seat pan exhibited downward crushing.
Examination of the cyclic and collective flight controls showed no evidence of preimpact failure or malfunction. The anti-torque control system had continuity from the pedals to a bearing that remained connected to the bellcrank assembly. The bottom of a fixed-tube assembly was fractured with no preimpact failure, and another fixed-tube assembly exhibited bending overload. Continuity was confirmed from the fixed-tube assembly to just forward of the tail rotor gearbox.
The tail rotor drive system showed continuity from the engine to just forward of the tail rotor gearbox, where the splined shaft had separated from the gearbox splined shaft. Both main rotor blades remained attached to the hub, but one blade had a 9-ft section that separated and was found about 100 ft from the helicopter's resting location. The engine assembly showed no evidence of preimpact failure or malfunction.
Additional Information
The FAA Civil Aeromedical Institute's publication "Introduction to Aviation Physiology" defines spatial disorientation as a "loss of proper bearings; state of mental confusion as to position, location, or movement relative to the position of the earth." Factors contributing to spatial disorientation include changes in acceleration, flight in IFR conditions, frequent transfer between VFR and IFR conditions, and unperceived changes in aircraft attitude.
The FAA's Airplane Flying Handbook (FAA-H-8083-3B) describes hazards when the ground or horizon is obscured. It states that the vestibular sense (motion sensing by the inner ear) can confuse pilots, as it cannot detect slight or uniform attitude changes and can generate false sensations, leading to spatial disorientation.