Sofema Aviation Services (SAS) considers an integrated approach to Product Auditing, considering Performance Auditing Techniques
Under AMC1 145.A.200(a)(6), your organisation must ensure that audits are:
- Independent (auditor not responsible for the audited function, procedure, or product),
- Sufficiently Frequent (to verify compliance, effectiveness, and continued conformity),
- Systematic (following a documented plan based on risk, complexity, and previous performance),
- Inclusive of the Entire Scope (organisation, facilities, personnel, procedures, products).
A proactive performance auditing approach moves beyond minimum compliance checks. It seeks to:
- Identify trends and patterns (e.g., recurring issues across aircraft types or maintenance tasks),
- Enhance safety and efficiency,
- Reduce risks before they manifest as non-compliances or incidents.
To do this effectively, you need flexible, risk-based audit planning — especially for product audits.
Product Audits in a Part-145 Environment with Multiple Aircraft Ratings
Here’s how to best approach this (Product Audits Should Be Risk-Based, Not Strictly Type-Based)
EASA doesn’t mandate “one audit per aircraft type.” Instead, focus on:
- The type of maintenance activity (e.g., C-checks, engine changes, cabin modifications),
- The specific risks and complexities involved (e.g., major structural repairs, avionics upgrades),
- Known problem areas or historical issues (e.g., recurring findings on a particular system),
- Emerging risks (e.g., new aircraft types recently added to scope).
Example – If your organisation maintains A320, A330, and B737, you don’t necessarily need a separate product audit for each type every year. Instead:
- Plan audits around maintenance events (e.g., a C-check audit that happens to be on an A330),
- Include representative samples across different aircraft types over the audit cycle,
- Rotate focus areas to ensure all aircraft types and maintenance activities are reviewed over time.
Audit Scope Must Be Representative and Systematic
While you can audit by activity type (e.g., line checks, engine runs, cabin refurbishments), you must ensure:
- The audit cycle covers all aircraft types within your approval over a reasonable timeframe (e.g., 24-36 months),
- Specific aircraft/system risk areas are reviewed,
- The approach is documented and justified in your Compliance Monitoring Program (CMP).
Link Product Audits to Compliance and Performance Goals
For each product audit, focus on:
- Regulatory compliance (per Part 145, Part M/Part CAMO interfaces),
- Effectiveness of procedures (are they practical and applied?),
- Evidence of human factors risks (e.g., errors during task sign-off, tool control lapses),
- Opportunities for improvement (e.g., safety culture, competence gaps).
Document a Risk-Based Product Audit Strategy
Your CMP should clearly state:
- Audit rationale (why you audit by activity, not by type),
- Risk considerations (e.g., complex maintenance events, new aircraft, known problem areas),
- Coverage assurance (how you ensure all aircraft types are eventually included).
Rotate Aircraft Types Across the Audit Cycle
While audits can focus on activity type, ensure no aircraft type is left unaudited for too long. A 3-year cycle is typically acceptable. (Note – Competent Authority Must Agree – Typically to Start with a 24 Months Cycle and escalate based on successful performance)
Maintain Flexibility for Emerging Risks
Adapt your plan to address issues as they arise—this demonstrates proactive performance auditing.
Cross-Reference Your AMP, SMS, and CMP
Align audit focus areas with known risks from your Maintenance Error Management System (MEMS), Reliability Reports, HF reports, and Safety Occurrence Reports.
Document and Defend Your Approach
Ensure your audit plan, risk assessment, and rationale are well-documented. This is key to satisfying EASA auditors and demonstrating a robust, risk-based approach.
Risk-Based Product Audit Strategy
This Product Audit Strategy outlines the approach adopted by [Company Name] to ensure systematic and effective auditing of maintenance products, in full compliance with EASA), AMC1 145.A.200(a)(6), and associated guidance.
The objective is to verify the conformity, airworthiness, and regulatory compliance of maintenance outputs across all aircraft and components maintained under the organisation’s approval.
Scope
This strategy applies to:
- All aircraft types and ratings within [Company Name]’s EASA Part-145 Approval,
- All maintenance activities, including but not limited to line maintenance, base maintenance, modifications, repairs, and engine/APU changes,
- All maintenance locations are operated by the organisation.
Risk-Based Audit Planning Principles
- a) Activity-Focused Audit Selection
Product audits will primarily be scheduled based on:
- The type of maintenance activity (e.g., C-Check, A-Check, Engine Change, Cabin Refurbishment),
- The complexity and criticality of the tasks involved,
- Known risk areas (e.g., Human Factors, tool control, defect rectification),
- Emerging issues (e.g., newly inducted aircraft, findings from previous audits, industry trends).
- b) Aircraft Type Inclusion Across Audit Cycle
While individual product audits may focus on specific maintenance events rather than aircraft type, the audit cycle (typically 24–36 months) will ensure that each aircraft type covered by the organisation’s approval is subject to at least one representative product audit during that period.
- c) Risk Factors Considered
Audit planning will take into account:
- Findings from previous audits,
- Safety reports, incident/occurrence data,
- Maintenance error reports and Human Factors analysis,
- New approvals, procedures, or technical changes,
- External inputs (e.g., regulatory updates, OEM advisories).
Audit Frequency and Coverage
Product audits will be distributed to provide:
- Representative coverage of all aircraft types,
- Focus on high-risk or complex maintenance events,
- A minimum frequency that ensures ongoing compliance and effectiveness verification.
The exact frequency and distribution of product audits will be documented in the Annual Compliance Monitoring Plan and adjusted as required based on risk assessments and performance data.
Documentation and Justification
- All product audits will be formally documented, including:
- The scope of the audit,
- The rationale for selecting the product/activity,
- The aircraft type(s) and maintenance activities audited,
- Findings, root cause analysis, and corrective actions.
- The Compliance Monitoring Manager will maintain a Product Audit Coverage Matrix to demonstrate that all aircraft types have been covered over the audit cycle.
- This strategy and its application will be reviewed annually as part of the Compliance Monitoring System Review and updated as necessary.
Integration with Performance Auditing Approach
This strategy supports a proactive performance auditing model by:
- Focusing audits on both compliance and continuous improvement,
- Identifying systemic risks, human factors, and opportunities for process optimisation,
- Feeding audit results into the Safety Management System (SMS), Reliability Program, and Human Factors feedback loops.
Next Steps
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Tags:
EASA Part 145, Performance Auditing, Regulatory Compliance, SAS blogs, Proactive Product, Sufficiently Frequent, Systematic, Entire Scope, Multiple Aircraft Ratings, Emerging risks, C-checks, Specific aircraft, Compliance Monitoring Program (CMP), human factors risks, Audit Strategy, Risk considerations
