Accident Overview
On April 2, 2023, at 1723 central daylight time, an Airbus Helicopters EC130 T2 helicopter, registration N231SH, was substantially damaged when it crashed near Chelsea, Alabama. The helicopter was operating as a Title 14 Code of Federal Regulations Part 135 air ambulance flight. The pilot and flight nurse were fatally injured, and the flight paramedic was seriously injured.
Witness Observations
Witnesses reported seeing the helicopter hovering about 100 ft away and 3 to 4 ft above the ground, facing south and parallel to the road. The helicopter then rapidly ascended, turned toward the road, moved above a car for several seconds, turned 180° back toward a field, and immediately pitched nose down, impacting the road. Another witness observed the helicopter hovering over a field; the tail went straight up before the helicopter flew sideways and hit the ground. Video from a deputy sheriff's dash camera showed the helicopter coming over trees, disappearing for about one second, then reappearing in a steep, nose-down attitude before impacting the road. The helicopter slid about 20 ft before coming to rest in the grass.
Pilot Information
The pilot held a helicopter pilot certificate with an instrument rating. His total flight experience was 8,965 hours, including 18 hours on the Airbus EC130 T2.
Wreckage and Impact Examination
The accident site was on a county road. Ground impact marks extended from the middle of the road to 20 ft on the roadside. The helicopter came to rest on its left side, oriented on a 116° magnetic heading. The forward fuselage and left windshield were breached; the instrument panel separated from its mount but remained intact. Heavy postcrash fire damage affected the engine compartment and transmission housing. Left side doors were separated; right side doors remained attached and closed.
The tail boom was structurally separated at the aft bulkhead but attached by cables and wiring. The Fenestron control cable was cut during recovery; manual actuation showed proper movement. The Fenestron exhibited impact damage; its gearbox chip detector appeared normal. The Fenestron short drive shaft separated at the flex coupling and was found outside the wreckage.
Hydraulic connections to main rotor servos were intact with no leaks; both reservoirs were nearly empty with thermally damaged supply hoses. The belt-driven hydraulic pump belt was partially consumed by fire. The main transmission was pushed down through the deck; three of four suspension bars were fractured. The lower transmission chip detector was damaged and could not be removed.
Main rotor blades remained attached; two star-flex arms had 45° fractures. Outboard blade sections showed broom-straw signatures consistent with ground impact. The cabin had a medical interior; forward cabin and flight controls were crushed aft about 2 ft. Flight control continuity was confirmed from cockpit to main rotor and Fenestron controls. The helicopter had a Gensys Heli-SAS autopilot. The roll trim actuator control rod was damaged and separated; pitch trim actuator was intact.
Fuel leaked from the fuel tank vent during recovery; the crash-resistant fuel tank was not breached but showed impact damage. The engine remained attached; cowling and inlet barrier filter were mostly consumed by fire. Engine fuel, oil, and air connections were properly secured but thermally damaged. Axial compressor blade leading edges had rough, serrated appearance consistent with hard body impact. Free turbine blade roots had overload fractures consistent with turbine blade shedding due to overspeed. The engine-to-transmission shaft flexible coupling was torsionally splayed. The splined coupling between free turbine shaft and reduction gearbox was disconnected.
Examination revealed no evidence of preimpact mechanical malfunctions or failures that would have precluded normal operation.
Medical and Pathological Information
The pilot's autopsy report listed cause of death as blunt force trauma. Toxicology testing detected cetirizine (169 ng/mL in cardiac blood, 564 ng/g in liver), norchlorcyclizine, cyclobenzaprine (19 ng/mL in blood, 216 ng/g in liver), norcyclobenzaprine (13 ng/mL in blood, 284 ng/g in liver), diphenhydramine (56 ng/mL in blood), and acetaminophen in cardiac blood and liver tissue. Cetirizine, cyclobenzaprine, and diphenhydramine are potential central nervous system (CNS) depressants, each carrying warnings against combination use due to possible sedation, impaired concentration, worsened reaction time, and psychomotor performance.
Cockpit Image Recorder Data
The on-board Appareo Vision 1000 cockpit image recorder was recovered and downloaded. Video showed that from takeoff to the hover over a gravel road, the flight was uneventful. During the hover, the helicopter moved slowly forward with normal flight control inputs. From the hover, fuel flow increased to about 7.4, and the helicopter moved forward about 50 ft as altitude increased. Trees were visible ahead. As altitude increased from about 50 ft to 110 ft agl, the attitude indicator showed over 20° nose-up pitch and 20° right roll. There was no appreciable change in pedal or cyclic position by the pilot. The helicopter then transitioned from nose-high to extreme nose-low attitude, continuing to roll right to a maximum of 30°. The pilot moved the cyclic left and aft without appreciable response. The attitude indicator tumbled, and the PFD displayed an obstacle indication. The video showed the helicopter impacting the road at a perpendicular angle.