Air Berlin flight AB2050 was operated with an Airbus A330-322 (D-AERQ) and took off on 15/08/2001 at 12:32 hrs from Düsseldorf Airport with 11 crew members and 383 passengers aboard.

Shortly after take-off of Air Berlin flight AB2050 the cabin crew member sitting next to door R2 heard a bang.

The area around the work lamp installed in the door became black, it started to smoulder and flames became visible. The cabin crew member reported her observation via intercom to the senior cabin crew member. The senior cabin crew member instructed the cabin crew members seated in positions 1L and 1R to go to door R2 to help the cabin crew member fight the fire and reported the incident to the cockpit crew.

AIR BERLIN flight AB2050

The cabin crew members sprayed Halon from a fire extinguisher onto the lamp and behind the door panel through existing openings. Afterwards no open flames could be determined. There was still smoke coming from the door panel, however.

After the cockpit crew had been informed they declared emergency and returned to the aerodrome of departure. The airplane landed there safely after a total of 13 minutes flight time.

Due to the climatic conditions in the door area condensation developed. Furthermore, whenever the door was open water could penetrate from the outside.

The water reached the power unit.

The BFU is of the opinion that the classification of the power unit as category W equipment in accordance with RTCA/DO-160C was not appropriate. The protection of the power unit against environmental conditions was sufficient in regard to the test procedures but not always in the real fitting situation.

In combination with the water the insulation resistance of the circuit board was reduced and resulted in a short circuit. The energy set free by the short circuit resulted in fire. The fire was noticed by the cabin crew which immediately initiated appropriate actions.

The fire was confined.

The BFU is of the opinion that to date the measures initiated by the manufacturer in the function as design organisation to remedy the known deficiency were insufficient to prevent in-flight fire.