Best Practices for Governance and SLAs in Continuing Airworthiness

An Engineering and Maintenance Organization is more than the sum of its roles—it relies on robust governance structures and clear service agreements to deliver safe, efficient, and compliant operations.

While understanding “who does what” is essential (covered in Inside the Engineering & Maintenance Organization: Who Does What?), ensuring accountability, performance, and coordination requires a different lens: governance and Service Level Agreements (SLAs).

Governance in Engineering and Maintenance

Effective governance ensures that the organization meets regulatory obligations, optimizes resources, and maintains operational reliability. Key principles include:

1. Regulatory Compliance
   Engineering and maintenance organizations must comply with applicable regulations such as EASA Part-M/CAMO, EASA Part-145, or FAA Part-145, which define requirements for continuing airworthiness management and maintenance organizations. Continuous monitoring of regulatory updates and assignment of compliance responsibilities are essential for safe operations.

2. Defined Roles and Responsibilities
   Governance complements the organization's functional structure by clarifying delegation of authority, reporting lines, and accountability. This ensures timely decision-making and prevents ambiguity in routine or emergency situations.

3. Documented Processes
   Standardized work ensures that maintenance and engineering tasks are performed consistently and in compliance with airworthiness standards. Policies, manuals, Standard Operating Procedures (SOPs), and Business Process Maps (BPM) formalize these workflows, providing clear guidance for staff.

4. Oversight and Performance Monitoring
   Internal audits, performance reviews, and Key Performance Indicators (KPIs) identify gaps, non-conformance, or inefficiencies, enabling corrective actions and continuous improvement. These oversight mechanisms are critical for both regulatory compliance and operational reliability.

Service Level Agreements (SLAs): Internal and External

A Service Level Agreement (SLA) is a formal agreement between two or more stakeholders to deliver a specific output of a process according to defined requirements, including timeframes, formats, processes, and quality standards. SLAs are used to ensure accountability, consistency, and alignment across internal departments or with external partners.

Internal SLAs

Internal SLAs manage interactions between engineering and maintenance departments. Some examples include:

• Technical Publications → Maintenance Programs: Release AMP source documents according to the agreed timeframe, using the defined format and approved IT tools.

• Maintenance Programs → Technical Publications: Submit the AMP following the established timeframe and process, in the prescribed format.

• Technical Services → Maintenance Programs: Provide analysis of Airworthiness Directives (AD), Service Bulletins (SB), and modifications within the agreed timeframe, in the standard reporting format.

• Maintenance Programs → Production Planning & Inventory Control: Submit new AMP tasks within the required timeframe prior to AMP approval, following the defined format and workflow.

• Component Repairs → Maintenance Teams / Production Planning: Return repaired components within agreed process timelines, in the defined format, ensuring traceability and serviceability.

Purpose: Internal SLAs improve operational coordination, accountability, and efficiency within the organization. They are typically embedded within manuals, SOPs, work instructions, or business process maps, providing a clear reference for deliverables, required formats, and processes.

External SLAs

External SLAs govern relationships with third-party providers such as MROs, component suppliers, or engineering consultancies. Common examples include:

• MRO Providers → Airline Maintenance Teams: Complete base or heavy maintenance events according to the agreed schedule, following approved work packages, checklists, and quality standards.

• Engineering Consultants → Engineering / Maintenance Teams: Provide technical assessments, modification approvals, or specialized analyses in accordance with agreed requirements and formats, using approved communication channels and reporting templates.

• Material Suppliers → Inventory / Maintenance Teams: Supply parts, tools, and materials meeting specification and certification requirements, delivered according to agreed schedules and tracking procedures.

Purpose: External SLAs maintain operational continuity, regulatory compliance, and accountability across organizational boundaries. They are normally formalized in contracts, service agreements, or documented procedures, specifying deliverables, formats, and timelines to ensure providers meet operational and regulatory requirements.

Best Practices for SLAs

• Define Scope Clearly
  Specify which maintenance or engineering services are covered by the SLA, including routine, unscheduled, and modification tasks. Clear scope ensures that all parties understand their responsibilities and reduces ambiguity in service delivery.

• Establish Measurable Metrics
  Use quantifiable indicators such as turnaround time, defect resolution, compliance rates, and reliability improvements to monitor SLA performance. Measurable metrics provide objective data to assess effectiveness and identify areas for improvement.

• Create Communication Protocols
  Set structured reporting channels, escalation paths, and feedback loops to maintain transparency and ensure timely resolution of issues. Effective communication protocols help align expectations across departments and with external partners.

• Enable Continuous Improvement
  Conduct regular SLA reviews, investigate deviations, and implement lessons learned. Continuous improvement ensures that SLAs remain relevant, practical, and effective as operational conditions or regulatory requirements evolve.

• Engage Stakeholders
  Involve relevant internal teams or external partners in the SLA development and review process to ensure agreements are realistic, achievable, and mutually beneficial. Stakeholder engagement fosters ownership and compliance.

• Document and Maintain SLAs
  Treat SLAs as living documents that evolve with regulatory updates, operational changes, and performance insights. Proper documentation formalizes expectations, provides a reference for accountability, and supports consistent execution of maintenance and engineering activities.

Conclusion

Clear accountability, structured oversight, and well-designed service agreements—both internal and external—help ensure that maintenance activities are executed efficiently, aircraft remain airworthy, and operational objectives are met. While understanding individual roles is important, effective governance and SLA practices enable the organization to operate as a coordinated and reliable system.

Implementing these frameworks supports compliance, improves coordination across departments and with external partners, and helps organizations use resources effectively while maintaining safety standards.

Learn how to use SLAs and best practices in aircraft maintenance processes →