British Aerospace Plc BAe 146-300 , VH-NJL

The co-pilot reported that during the BAe 146 handover, the previous crew stated that the aircraft had an air-conditioning contamination problem and that it appeared to emanate from the No. 2 air-conditioning pack. On entering the aircraft the co-pilot noted that only the No. 2 pack was operating and the ambient air was contaminated. The crew switched off the No. 2 pack until the engines were started and the aircraft had taxied to the runway holding point.

After take-off, the co-pilot reported that he began to feel nauseous and had developed a headache. After discussing the problem with the aircraft captain, he donned an oxygen mask and gradually felt better. During the flight, a flight attendant entered the cockpit and reported a soreness of the head, and that she felt nauseous.

On the return flight, the crew left the No. 2 pack switched off. They reported that the contamination was far less noticeable than the previous flight.

Inspection by the company maintenance personnel did not initially find any evidence of contamination. However, the co-pilot reported that subsequent replacement of the aircraft auxiliary power unit appeared to have rectified the air contamination problem.