What happened
On 15 November 2006, an Airbus A320-214, registration G-BXKD, performed a heavy landing at Bristol Airport during a period of significant turbulence and strong crosswinds. The landing exceeded specific safety parameters, triggering an automated aircraft warning known as a LOAD <15> report. While the flight crew recorded the event in the technical log, the aircraft was subsequently cleared for further service.
During a subsequent flight, the crew encountered difficulties raising the landing gear accompanied by several ECAM warnings, necessitating a diversion to Manchester Airport. Despite further engineering inspections, the aircraft was released for another flight, only to experience a repeat of the landing gear issues and additional warnings after takeoff. The underlying cause—internal damage to the right main landing gear—was only identified after the aircraft was jacked for inspection following the second arrival at Manchester.
The investigation
The AAIB investigation focused on why the structural damage to the landing gear's upper diaphragm tube remained hidden during initial inspections. Investigators examined the maintenance procedures performed at Bristol, specifically the use of the AirN@V computerised manual system. It was found that the engineer at Bristol, who had limited experience with the software, followed a maintenance task that did not require jacking the aircraft. This task was an outdated version of the required check, as the more recent, comprehensive procedure (AMM 05-51-11-200-004A) was not easily located within the digital menu structure.
Furthermore, the investigation looked into the lack of connection made between the initial heavy landing report and the subsequent sensor failure (20GA) observed at Manchester. The investigation also reviewed the effectiveness of the Airbus maintenance manuals and how they communicated the impact of various Service Bulletins on specific aircraft.
Findings
- The initial landing at Bristol was a hard landing caused by high-intensity turbulence and a crosswind that approached the aircraft's demonstrated limits.
- The autopilot was disconnected too close to the runway threshold, leaving the crew insufficient time to manage the aircraft during the flare in turbulent conditions.
- The maintenance engineer at Bristol lacked adequate training in navigating the AirN@V software, which hindered the discovery of the more recent, appropriate inspection task.
- The Airbus maintenance manuals contained ambiguous effectivity coding, making it difficult to distinguish which instructions applied to aircraft following specific Service Bulletins.
- There was a failure to link the 20GA sensor fault to the previous heavy landing report, which would have pointed toward internal landing gear damage.
- The guidance within the aircraft manuals for interpreting the LOAD <15> report was inconsistent and lacked clarity regarding necessary corrective actions.