Eurocopter EC155 B1, G-ISSV
The aircraft was being refuelled on the ramp with the rotors running when a localised fire broke out in the area of the external connector for the electric hoist, on the upper right side of the fuselage. The fire went out as soon as electrical power was removed on shutting down the engines. The investigation established that the fire was caused by the 28 volt DC electric hoist power supply shorting to the body of the hoist’s fixed electrical connector and earthing through the carbon fibre composite fairing on which the connector is mounted. The short was probably caused by moisture ingress into the connector due to a damaged seal. A contributory factor was that the connector is always live whenever the electrical system is powered. Three safety recommendations are made to the aircraft manufacturer.
Eurocopter EC155 B1, G-ISSV 11-07.pdf (418.25 kb)