What happened
On 3 November 2000, at approximately 1945 hours UTC, a Fokker F28 Mark 0100, registration G-BYDN, was conducting an approach to Paris Charles de Gaulle Airport. During the course of the investigation into the aircraft's systems, technical details regarding the elevator control mechanisms were reviewed.
The investigation
The AAIB examined the elevator control architecture, specifically focusing on the components within the bullet fairing. The investigation looked at the interaction between the push-pull rods, the elevator booster control unit, and the cable tension regulator. A key area of focus was the servo drive cables and the elevator autopilot servos, as well as the flight control lock mechanism.
Technical scrutiny was applied to the servo motor capstan cable grooves. The investigation identified the necessity of comparing the current groove configuration against a modified groove design. This examination was part of a broader review of the mechanical interface between the cables and the servo mounts.
Findings
- The investigation established the importance of the modification to the servo motor capstan cable grooves.
- This modification is documented under Service Bulletins SBF100-22039 and SBF100-22-047.
- The physical changes involve the transition from the current groove state to a modified groove state on the servo mount capstan.