History of Flight
On January 9, 2020, at approximately 2029 eastern standard time, a Robinson R66 helicopter (registration N450MC) was destroyed following an accident near Mechanicsburg, Pennsylvania. The private pilot and a passenger were fatally injured. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal trip.
The pilot filed for VFR flight following from Martin State Airport (MTN) in Baltimore, Maryland, to Buffalo Niagara International Airport (BUF) in Buffalo, New York, at an altitude of 3,000 ft mean sea level. The helicopter departed after receiving clearance and climbed to about 2,300 ft, proceeding north-northwestward. At 2023:15, the Harrisburg approach controller instructed a heading of 310°, which the pilot followed. At 2028:50, the helicopter began descending; radar contact was lost at 2029:17 at an altitude of about 1,150 ft. A "grunt-type sound" was recorded on the approach frequency around 2029.
Flight data from the Garmin GTN 750, GDU 1060, and engine monitoring unit showed no significant pitch or roll excursions until 2028:46, when pitch began oscillating and a left roll developed. The roll increased rapidly; engine torque spiked and then decreased. Acceleration reached -1 G. Airspeed dropped to zero at 2029:08. By 2029:11, the helicopter was in a left roll of 179° and pitch of -23°. The main rotor appeared to separate between 2029:11 and 2029:12, as indicated by the sound spectrum in a doorbell camera video.
Personnel Information
The pilot had been diagnosed with obstructive sleep apnea and coronary artery disease in 2001 and 2009, respectively. Cardiac catheterization revealed mild-to-moderate triple-vessel coronary artery disease not requiring intervention. He used a CPAP device with good adherence; records showed 85% use in the preceding year and nightly use in the week before the accident. The pilot attended a Robinson R66 safety course in February 2019, at which time he had no hours in type. The instructor rated his control as "very good" and suggested additional emergency procedure training.
Aircraft Information
The helicopter was manufactured in January 2019 and had logged about 167 hours. It featured a semirigid rotor system (counterclockwise rotation). Robinson Safety Notice 11 addresses low-G pushover risks. The helicopter was equipped with a Genesys Aerosystems HeliSAS two-axis autopilot; its fault data were unreadable. The SAS mode engages stability augmentation; disengagement produces four aural beeps.
Meteorological Information
At cruising altitude (2,300 ft), wind was from 190° at 27 knots. There was an 87% probability of moderate-to-severe turbulence. Pilot reports confirmed strong-to-severe low-level windshear and turbulence in the area. The handbook recommends 60-70 knots in significant turbulence. No precipitation echoes were present. The sun had set, moon was 99% illuminated.
Wreckage and Impact
The helicopter crashed in a residential backyard about 61 miles north-northwest of MTN. The fuselage was nearly inverted, resting on its right side. The tailboom was found in a tree; a ground scar indicated impact. Main rotor blade sections were scattered, with one piece 700 ft away. Feathers from a mourning dove were found on a blade section and adjacent ground. No evidence of preimpact failure was found in the engine, transmission, or flight controls. The tailboom showed damage consistent with main rotor blade contact. The sprag clutch and autopilot components were tested; the roll servo failed a system-level test, possibly due to internal wire damage.
Additional Information
A doorbell camera captured 22.8 seconds of video and audio. Spectral analysis indicated both rotors operated normally until about 12 seconds into the video, after which main rotor contribution ceased. A large signal transient likely corresponded to main rotor separation.
Two iPhones were recovered. The pilot's last incoming call ended at 2008:18; last text sent at 2010:20. No relevant data were found on the passenger's phone.
The helicopter was not equipped with a flight data recorder or cockpit voice recorder. The NTSB had recommended such recorders on turbine helicopters; Robinson began installing cockpit cameras in 2021, though not crash-resistant.
Medical and Pathological Information
An autopsy of the pilot was performed by Forensic Pathology, Cumberland County Coroner's Office.