History of Flight
On July 4, 2019, at 01:53 local time, an Agusta S.p.A. AW139 helicopter, registration N32CC, sustained substantial damage after impacting water near Big Grand Cay, Abaco, Bahamas. The two pilots and five passengers were fatally injured. The flight was conducted under Part 91 personal rules.
The helicopter departed from a brightly lit helipad at approximately 01:52. The flight proceeded over water in dark night conditions with no visible moon, likely zero ambient illumination, and no visible horizon. After takeoff, the pilot-in-command (PIC) manipulated the cyclic and antitorque control pedals and engaged the collective pitch trim. The cyclic force trim release (FTR) switch remained engaged throughout the flight. The helicopter began to descend with increasing airspeed and a nose-down attitude. The first of numerous enhanced ground proximity warning system (EGPWS) warnings sounded. At about 01:52:50, while at 110 ft radio altitude descending at 1,380 ft per minute, a pilot engaged the autopilot in altitude acquire (ALTA) mode with airspeed hold. The ALTA rate of climb was reset to +100 ft per minute due to system design.
Despite EGPWS warnings, the PIC continued commanding forward cyclic. At 01:52:51, the PIC pulled the cyclic back and initiated a second climb. He asked the SIC for altitude but received no response; the SIC later advised the helicopter was not at 300 ft but diving. The helicopter climbed above 150 ft but subsequently began descending again. The PIC repeatedly applied forward cyclic, and the helicopter entered a left descending turn with increasing airspeed and engine torque. The PIC asked for heading and altitude, but the SIC did not respond. At 01:53:22, the helicopter impacted the water at high speed in a nose-down, left-bank attitude.
Analysis
The flight crew did not conduct a formal preflight instrument briefing. Their pretakeoff conversation involved flight plan details, altitude, heading, navigation, and flight computer programming. They did not discuss night takeoff over water or crew roles and responsibilities. This limited planning indicated inadequate crew resource management (CRM).
After takeoff, the PIC likely perceived accelerations from increasing forward airspeed as the helicopter pitching up, leading to improper control inputs consistent with somatogravic illusion, a type of spatial disorientation. The PIC did not effectively use instruments to recognize the helicopter's flightpath. The SIC recognized the first descent, and the PIC selected ALTA, which helped recover altitude. However, the PIC continued commanding forward cyclic, causing a second descent. Multiple EGPWS warnings sounded, but the PIC did not arrest the descent.
Examination of the flight control system, autopilot, structures, main and tail rotor, and engines found no preimpact mechanical failures. All damage was consistent with water impact.
Probable Cause and Findings
The National Transportation Safety Board determined the probable cause as: "The pilots’ decision to takeoff over water in dark night conditions with no external visual reference, which resulted in spatial disorientation and subsequent collision with the water. Also causal was the pilots’ failure to adequately monitor their instruments and respond to multiple EGPWS warnings to arrest the helicopter’s descent. Contributing to the pilots’ decision was external pressure to complete the flight. Contributing to the accident was the pilots’ lack of night flying experience from the island and their inadequate crew resource management."