What happened
On 9 April 2007, a Piper PA-28R-201T Turbo Cherokee Arrow III, registered G-JMTT, was involved in an incident approximately 9 nautical miles south of Oban (North Connel) Airport in Argy/Argyll and Bute, Scotland. The aircraft was operating in the area at approximately 10:50 UTC.
The investigation
The AAIB conducted a field investigation into the circumstances surrounding the event. The inquiry focused on the operational integrity of the aircraft's flight instruments and the maintenance protocols governing critical engine-driven components.
Findings
The investigation established the necessity of strict adherence to maintenance and replacement schedules for vacuum pumps. Specifically, the findings emphasized that for aircraft utilizing vacuum-driven Attitude Indicators, compliance with specific maintenance limits is essential to ensure safe operation during Instrument Meteorological Conditions (IMC).
Safety action
Following the investigation, several safety recommendations were issued to various aviation authorities and manufacturers:
- The European Aviation Safety Agency (EASA) was advised to mandate compliance with vacuum pump maintenance and replacement requirements to ensure the safety of aircraft operating in IMC.
- The US Federal Aviation Administration (FAA) was recommended to implement similar mandates for vacuum pump maintenance and replacement.
- The Civil Aviation Authority (CAA) was advised to publicize the specific vacuum pump replacement requirements detailed in Parker Airborne Service Letter 58A to operators and maintenance personnel.
- The New Piper Aircraft Company was advised to revise its maintenance manuals to ensure consistent vacuum pump maintenance requirements across its entire product range.