What happened
On 5 July 2002, an Embraer EMB-145EP, registration G-ERJE, was performing a scheduled passenger flight from Paris Charles de Gaulle to Bristol International Airport. During the descent towards Bristol, the crew was managing a high rate of descent required by air traffic control constraints. As the aircraft approached the runway 27 ILS, it encountered an overspeed condition, prompting the commander to disconnect the autopilot and fly the aircraft manually.
During the process of re-establishing the localiser course, the aircraft's descent rate increased significantly. At approximately 1,600 feet amsl, the aircraft was descending at roughly 5,000 feet per minute. The crew became aware of the altitude deviation through several means, including a Ground Proximity Warning System (GPWS) alert, visual contact with the ground, and verbal warnings from air traffic control. The commander promptly initiated a climb, bringing the aircraft back to 2,400 feet amsl to complete a safe approach and landing. There were no injuries and no damage to the aircraft.
The investigation
The AAIB investigation examined the flight profiles, cockpit workload, and the aircraft's technical performance. Investigators reviewed radar data, which confirmed the aircraft had struggled to maintain the localiser centerline, passing through it multiple times. The investigation also looked into the timing of the approach checklist and the impact of the landing gear being selected 'down' during the descent.
Findings
- The high rate of descent required by the arrival profile, combined with an overspeed warning, significantly increased the pilot's workload.
- The selection of the landing gear during the descent increased drag, contributing to the rapid loss of altitude.
- Standard operating procedures for flight progress monitoring were not fully maintained during the high-workload phase.
- The aircraft type had a documented history of difficulties with localiser capture and tracking.
- The presence of an extra crew member for FMS familiarisation may have contributed to increased cockpit workload.