What happened
On 28 May 2008, a DHC-8-402 Dash 8, registration G-JEDU, was conducting a scheduled passenger flight from Exeter Airport to Paris Charles de Gaulle Airport. The flight was being used for line training, with the commander supervising a co-pilot acting as the handling pilot.
During the approach to runway 27R, the aircraft was instructed by air traffic control to maintain a speed of 180 kt until reaching 4 nm from the runway. As the aircraft approached the 4 nm mark, the power levers were reduced to flight idle. At 500 ft altitude, the indicated airspeed was approximately 136 kt, which was 22 kt above the reference speed (VREF).
As the aircraft descended to approximately 120 ft, the airspeed dropped below the required VREF. The commander noted the low speed, but the co-pilot only increased the power levers to 8% torque, a setting significantly lower than the 14-15% required for the configuration. The airspeed continued to decay, and the aircraft eventually touched down on its tail at 103 kt, which was 11 kt below VREF. The impact caused damage to the rear underside of the main fuselage. There were no injuries to the 4 crew members or 37 passengers on board.
The investigation
The AAIB examined the flight's approach stability and the crew's adherence to company procedures. The investigation found that the approach was not stable at 500 ft, as the speed exceeded the permitted threshold and the co-pilot failed to call out the altitude. Furthermore, the commander did not perform the required speed call-outs every 100 ft below 500 ft.
The investigation also looked into the commander's recent medical history. The commander had been hospitalized and discharged only 23 days prior to the accident. He reported feeling progressively more tired during the week leading up to the event and noted a lack of timely reaction during the low-speed event.
Findings
- The approach was unstable at 500 ft because the airspeed was too high and the required altitude call-out was not made.
- The commander failed to intervene or take control when the airspeed dropped below VREF.
- The co-pilot's power increase was insufficient to maintain the required approach speed.
- Post-infectious fatigue following the commander's recent hospitalization likely contributed to a lack of alertness and delayed decision-making.
- The commander's return to flight duties occurred shortly after a period of illness, which may have impacted his physiological readiness.