Background
The day before the incident, a Bell 407 helicopter was approaching Kerrville, Texas, when the RESTART FAULT light illuminated on the caution and warning panel after flying through light rain. The flight continued to Kerrville and landed without further incident. Maintenance was performed to address the issue.
On the day of the incident, the helicopter's engine was started and run on the ground twice, with all systems operating normally. A 10-minute test flight revealed no discrepancies.
Incident Description
During the approach to Kerrville Airport, at an altitude of 300 feet above ground level (AGL) while in a right turn at approximately 60 knots, the pilot noticed the FADEC FAIL light and heard the warning horn. The pilot initiated an autorotation. To avoid trees and houses, the pilot extended the glide by increasing collective pitch. After clearing the obstacles, he leveled the helicopter and applied full remaining collective for landing. The helicopter touched down hard but remained upright.
The pilot did not perform the emergency procedure for a FADEC FAIL warning light as specified in the Bell 407 Rotorcraft Flight Manual.
Examination
An examination of the HMU (Hydromechanical Unit) harness revealed a manufacturing defect.