Continued Airworthiness & Maintenance

A legally enforceable regulation issued by an airworthiness authority that mandates inspection, modification, operational limitation, or replacement actions on an aircraft, engine, propeller, or appliance to correct an unsafe condition. Compliance with an AD is mandatory for continued operation of the affected product. ADs are issued when an unsafe condition exists or is likely to exist in other products of the same type design.

A document issued by the type certificate holder (aircraft, engine, or equipment manufacturer) that provides instructions for inspection, modification, or repair of a product to address a design improvement, reliability enhancement, or safety concern. Service bulletins are generally not mandatory unless mandated by an Airworthiness Directive, although operators may choose to implement them voluntarily to improve safety, reliability, or performance.

The set of documents provided by the type certificate holder that contains the information necessary for an operator to maintain an aircraft, engine, or appliance in an airworthy condition throughout its operational life. ICAs include the maintenance manual, overhaul manual, structural repair manual, illustrated parts catalogue, wiring diagram manual, and scheduled maintenance requirements, as well as airworthiness limitations that are regulatory-approved and mandatory.

A set of interrelated concepts defining the initial scheduled maintenance program for transport category aircraft. MSG-3 (Maintenance Steering Group - 3) is the analysis methodology used to develop the initial scheduled maintenance requirements. The Maintenance Review Board (MRB) is the regulatory body that oversees the MSG-3 process and approves the resulting Maintenance Review Board Report (MRBR), which defines the minimum initial scheduled maintenance tasks and intervals. The Maintenance Planning Document (MPD) is the TC holder's document that incorporates the MRBR requirements along with additional manufacturer recommendations.

14 CFR Part 43 (FAA) defines the standards and rules for maintenance, preventive maintenance, rebuilding, and alteration of aircraft, engines, propellers, and appliances. It establishes who is authorized to perform maintenance, what standards must be followed, and what records must be kept. Equivalent regulations exist in EASA (Part-M and Part-ML for continuing airworthiness management, Part-145 for maintenance organizations) and TCCA (CAR 571 for maintenance requirements, CAR 573 for approved maintenance organizations).

A maintenance facility certificated by the aviation authority to perform maintenance, preventive maintenance, and alterations on aircraft, engines, propellers, and appliances. In the FAA system, these are certificated under 14 CFR Part 145 as Repair Stations. In EASA, they are approved under Part-145 as Maintenance Organisations. In TCCA, they are approved under CAR 573 as Approved Maintenance Organizations (AMOs).

An organisation approved by EASA (under Part-M Subpart G, or Part-CAMO for air carrier aircraft) to manage the continuing airworthiness of aircraft and their components. The CAMO is responsible for ensuring that all required maintenance is planned, scheduled, and accomplished, that the aircraft configuration is properly managed, and that the aircraft remains in compliance with its approved maintenance programme, ADs, and airworthiness limitations throughout its operational life.

The Master Minimum Equipment List (MMEL) is a document established by the type certificate holder and approved by the certification authority that identifies equipment and instruments that may be inoperative for dispatch under specified conditions and limitations, while still maintaining an acceptable level of safety. The Minimum Equipment List (MEL) is the operator-specific document, derived from the MMEL, tailored to the operator's specific aircraft configuration, operations, and maintenance capability, and approved by the operator's national aviation authority.

A data-driven program that monitors the in-service performance of aircraft systems and components to detect adverse trends, identify reliability issues, and provide a basis for adjusting maintenance tasks and intervals. The reliability program collects and analyzes data on component removals, failures, delays, cancellations, pilot reports, and maintenance findings to assess whether the aircraft maintenance program remains effective.

Escalation is the process of extending scheduled maintenance task intervals beyond the initial intervals established in the MRBR/MPD, based on accumulated in-service reliability data demonstrating that the current intervals are conservative and that safety is maintained with longer intervals. Bridging is the transitional process of extending intervals from the current approved interval toward a target interval in defined steps, with reliability monitoring at each step to confirm that the extended interval remains adequate.

The systematic process of tracking and managing the physical configuration of each aircraft and its components throughout the operational life, ensuring that the aircraft conforms to its approved type design (including all incorporated modifications, service bulletins, and airworthiness directives) and that the configuration is accurately documented in the aircraft's continuing airworthiness records.

The process of recording and monitoring the current modification status of each aircraft and its individual components, including which service bulletins have been incorporated, which ADs have been complied with, and the current part number, serial number, and software version of each installed item. Modification status tracking ensures that each aircraft's physical configuration is accurately known and documented at all times.