What happened
On 14 June 2022, an Airbus A320-232, registration G-EUUT, was performing a commercial passenger flight from Malaga to London Heathrow. During the arrival phase, approximately five minutes before landing, the co-pilot detected a strong, unpleasant odour in the flight deck, described as similar to wet dog or sweaty socks. The commander also noted the smell.
Because the flight crew was managing a high workload during the approach, they chose not to initiate the Quick Reference Handbook (QRH) smoke and fumes procedures. Consequently, neither pilot donned oxygen masks during the descent. The aircraft landed without incident, and the odour ceased to be noticeable as the aircraft taxied toward its stand.
While waiting for parking guidance, the co-pilot began to feel nauseous and lightheaded. Upon reaching the stand, the co-pilot's condition worsened to include coughing and retching. The commander also began to feel unwell. The commander subsequently shut down the engines, declared a PAN alert, and opened the cockpit window. Cabin crew provided portable oxygen sets to both pilots. A 17-minute delay occurred before an airbridge was attached, delaying the arrival of paramedics and the fire service.
The investigation
The investigation focused on the source of the odour and the crew's response. The aircraft was removed from service for a specialized maintenance inspection. Technicians used gas monitors and specialized equipment to detect volatile compounds, such as hydraulic fluid or lubricating oil, but all tests returned negative results. No technical fault was identified, and the aircraft returned to service.
Investigators also examined the crew's decision-making regarding the QRH. While the procedure is complex and not intended to be performed from memory, the operator's training emphasizes the importance of donning oxygen masks to provide positive pressure against potential toxins. The investigation also noted the delay in emergency services accessing the flight deck due to ground handling limitations.
Findings
- The crew did not perform the smoke/fumes QRH procedures due to high workload and an initial lack of physical symptoms.
- The delay in ground personnel accessing the aircraft prevented immediate medical assessment and potential mitigation of exposure.
- Gas monitoring by the RFFS and maintenance personnel found no evidence of combustible or toxic gases.
- The commander was taken to hospital for assessment due to elevated pulse and blood pressure but was released after blood tests were negative for toxins.