• Within the certification and airworthiness system there are three basic processes to set and maintain required standards.
These processes determine and maintain the intended level of safety:
⁃ Initial airworthiness processes;
⁃ Continuing airworthiness processes;
⁃ Continued airworthiness processes.
• The initial airworthiness processes are those used to determine the applicable requirements, and establish that an aircraft design is demonstrated to be able to meet these requirements. This includes the safety targets and the development of instructions for use and ongoing care/maintenance. Within the EASA framework, which adopted in the UK, it would also cover the elements of production, i.e. those aspects of taking the approved design and manufacturing the end product of the point of a useable aircraft. This phase is therefore complete prior to an aircraft entering into service.
• The continuing airworthiness process refers to the system of management of the aircraft and the scheduling and actioning of ongoing preventative and corrective maintenance to confirm correct functioning and to achieve safe, reliable and cost effective operation.
• Continued airworthiness refers to the monitoring, reporting and corrective action processes used for in-service aircraft to assure they maintain the appropriate safety standard defined during the initial airworthiness processes throughout their operational life.
• In parallel with each of these processes, there are schemes that require or provide of organization approvals, e.g. design, production, maintenance and organization approvals. These approvals enable the NAAs to recognise capability with a company system; this limits the level of investigation and oversight that may be necessary to establish compliance against the regulatory standards applicable to individual products.
• The initial airworthiness process is intended to establish a desired level of airworthiness integrity for an aircraft and to demonstrate that this level of integrity airworthiness integrity for an aircraft and to demonstrate that this level of integrity can be achieved. In this case, integrity can be taken to include all aspects of the design (structurally and systemically) to cover safety, reliability, availability, capacity, etc. When the desired level of airworthiness integrity is met and consistently shown to be achieved, the aircraft can be considered to provide an acceptable level of safety; this covers both the vehicle (and any person (s) on board, if applicable) and, by inference from continued safe flight, to persons and property on the ground.
• The initial airworthiness processes have to following basic elements for design and production:
⁃ Establishment of the design/certification requirements (certification specifications) which define the high level design criteria and showing that these are met.
⁃ The design organization aspects which covers the capacity and competence of the company for the design of the complete aircraft, systems or individual parts.
⁃ The production organization aspects which cover the capability and competence for the manufacture and assembly of the complete aircraft, systems or individual parts in accordance with the approved design and testing of the aircraft prior to delivery.
• The design organization is charged with demonstrating to the certification authority that the proposed design is compliant with the established and agreed certification specifications or other requirements. Similarly the production organization is responsible to show the end profits conformance to the design.
• The continuing airworthiness process are intented to assure that in-service aircraft are managed and maintained and that these actions are performed correctly, by appropriately capable persons, in accordance with the instructions developed by the design organization so that assumptions an considerations made during the design, particularly in respect of safety, remain valid. As a result, these processes also need effective communication between the operator, maintenance organizations and the design organizations to ensure that necessary information is shared and if necessary corrective actions taken.
• The continuing airworthiness process will support any modifications, repair or component replacement once an aircraft has entered service. This is achieved by not only undertaking the incorporation of the changes, but also in the management of configuration records, updating of maintenance instructions, etc.
• The continued airworthiness processes are intended to provide a closed loop monitor and corrective action cycle for in-service aircraft to assure that the intended level of safety is maintained. The process starts with activity within the certification work (for example the development of the maintenance schedules and instructions on how to perform this activity). Thereafter, it includes the monitoring of experience of in-service aircraft and, when necessary, the definition and promulgation of corrective action instructions.
• The development of maintenance schedules typically considers and uses information from the aircraft design and safety assessment processes to determine what maintenance activities are required and how frequently they will be performed to maintain the appropriate level of aircraft integrity (for example replacing parts before they would typically wear out or fail will prevent the consequence of this and hence aid both safety and commercial costs).
• The monitoring and reporting processes support the collection and analysis of in-service information and enable the design organization to be satisfied that the overall level of safety is being archived, or if necessary, to determine and promulgate corrective actions to address problem areas.
• If these programmes are run correctly, they have the potential to save organizations money – it is usually cheaply in terms of both money and time to fix a minor problem before it becomes a serious problem.