Safety Recommendation: 2021-022
2021-022: It is recommended that the Civil Aviation Authority (CAA), during future audits of CAA-approved Continued Airworthiness Management Organisations and Approved Maintenance Organisations, include a check that consideration has been given to the classification of biocide treatment of aircraft fuel systems as a critical maintenance task.
The Civil Aviation Authority (CAA), as part of its future audit oversight programme for Continued Airworthiness Management Organisations and Approved Maintenance Organisations, will review the use of critical maintenance task methods and procedures highlighting to organisations, including the classification of biocide treatment of aircraft as indicated within the AAIB report. This will include the need to follow guidance material as set out in GM M.A.402(h) or AMC2 145.A.48(b) for data sources used for the identification of critical maintenance tasks which includes accident reports.
As an additional mitigation the CAA will amend its guidance material on the creation and amendment of Aircraft Maintenance Programmes to include additional guidance on identification of critical maintenance tasks highlighting the above mentioned regulatory references and the need to place additional focus on Biocide treatment of aircraft.