What happened
On 2 February 2006, a BAe 146-300, registration G-JEBA, was performing a scheduled passenger service from Belfast City Airport to Gatwick. During the climb phase of the flight, the co-pilot, who was acting as the handling pilot, detected an odour in the flight deck air similar to that of a central heating boiler. While the commander did not notice the smell, the co-pilot soon began experiencing a dry throat, burning eyes, and a tingling sensation in his fingers, alongside feeling hot and sweating.
In response to these symptoms, the co-pilot donned an oxygen mask and moved his seat back, effectively withdrawing from flight duties. Although the oxygen mask did not immediately alleviate his symptoms, the commander took control of the aircraft and elected to return to Belfast. While the flight crew and passengers remained unaffected, some cabin crew members reported detecting fumes and an odour within the cabin air. The aircraft landed safely at Belfast, and the co-pilot was transported to a hospital for medical evaluation.
The investigation
Investigators examined the aircraft's engines, APU, and air conditioning systems using manufacturer service documentation. The inspection identified light deposits within the air conditioning ducting that supplies the flight deck and cabin. Additionally, an oil leak was discovered in the APU bay, originating from the APU generator oil air-cooled oil cooler. However, investigators determined that because the APU's cooling air system is separate from the main aircraft bleed air system, this specific leak was unlikely to have entered the passenger air supply.
Findings
- The co-pilot suffered minor injuries and physical symptoms following exposure to contaminated air.
- Light deposits were present in the air conditioning ducting.
- The presence of unidentified fumes in the air supply was the primary factor affecting the co-pilot.
- While an oil leak was present in the APU bay, it was not considered the source of the cockpit contamination.
- Blood tests performed on the co-pilot following the incident were inconclusive.