What happened
On 28 February 2019, an Embraer 195, registration G-FBEJ, was preparing for a scheduled passenger flight from Exeter Airport to Alicante. During the initial stages of takeoff, the flight crew noticed a change in odor and observed smoke entering the cockpit. The crew immediately retarded the thrust levers to idle and applied the parking brake.
As the situation progressed, the cabin crew reported smoke and fumes throughout the cabin. The commander subsequently ordered an emergency evacuation. During the egress, passengers using the overwing exits experienced difficulty descending to the ground. Some passengers found the wing surface slippery and were unsure of the correct path, leading some to re-enter the aircraft to find alternative exits. The evacuation resulted in one serious injury and one minor injury.
The investigation
The AAIB investigation focused on the source of the fumes and the efficiency of the evacuation. Investigators established that the smoke and fumes originated from residual detergent left in the engine compressor bleed ducts. This was the result of an engine compressor wash performed the previous night.
The investigation found that the maintenance personnel had performed the wash using a water and detergent mix but did not perform a high-power engine ground run. While the engine manufacturer's manual suggested a high-power run to dry the ducts, it was only a recommendation rather than a requirement. Because the engine was only run at idle power, the bleed source did not switch to the stage necessary to purge the residual cleaning solution.
Regarding the evacuation, the investigation found that the aircraft's flaps had not fully extended to the selected position before the engines were shut down. This increased the vertical drop from the wing to the ground. Furthermore, the markings on the wing intended to guide passengers were not easily noticed by those evacuating.
Findings
- The primary cause of the smoke and fumes was residual cleaning solution remaining in the engine bleed ducts following an incomplete drying process.
- The maintenance task was assigned to an engineer who lacked the specific authorization to perform high-power engine ground runs on this aircraft type.
- The engine manufacturer's manual did not mandate a high-power run to dry the ducts, only recommending it.
- The evacuation was hindered by the increased height of the wing trailing edge because the flaps had not reached the commanded position.
- Overwing exit markings lacked sufficient conspicuity to guide passengers effectively during the emergency.