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A type certificate is issued to signify the airworthiness of an aircraft manufacturing design. The certificate is issued by a regulating body, and once issued, the design cannot be changed. The certificate reflects a determination made by the regulating body that the aircraft is manufactured according to an approved design, and that the design ensures compliance with airworthiness requirements. The regulating body compares design documents and processes to determine if the design meets requirements established for the type of equipment. Requirements established by a regulating body typically refer to Minimum Operating Performance Standards (MOPS) and related documents (such as DO-178 series, DO-160 series and DO-254 series), which are developed jointly by RTCA, Inc. and EUROCAE. Once issued, the aircraft "type" meets appropriate requirements. The determination process includes a step called "First Article Inspection", for it and for each of its subassemblies. This is a quality control assessment whereas those prior to it are part of quality assurance. With respect to "cannot be changed": When an airframer wants to change something it has two options. One is to request a Supplemental Type Certificate (STC), the other is to create an entirely different design. The choice is determined by considering whether or not the change constitutes a new design (i.e. introduces risk not considered in the first design). If the manufacturer believes the change doesn't introduce new risk the manufacturer typically requests an STC. This is less expensive. If the regulatory authority agrees with the rationale for choosing STC, the STC is granted. *The type certificate (TC) implies that aircraft manufactured according to the approved design can be issued an Airworthiness Certificate. Examples of regulatory authorities are the Civil Aviation Authority (CAA), the Federal Aviation Administration (FAA) and the (European Aviation Safety Agency (EASA). To meet those requirements the aircraft and each sub-assembly must also be approved. For example, in the U.S. these sub-assemblies must meet requirements in the applicable Technical Standard Order (TSO). To meet those requirements the design documents are examined for compliance with the applicable Minimum Operating Performance Standards (MOPS) applicable to that sub-assembly. MOPS are published by RTCA, Inc. When aircraft are produced to meet a given TC, each one need not be tested as rigorously but the confidence demonstrated by the TC is conferred, when the aircraft has been assigned an Airworthiness Certificate. *An "Airworthiness Certificate" is issued for each aircraft that is properly registered if it conforms to its type design. The airworthiness certificate is valid and the aircraft may be operated as long as it is maintained in accordance with the rules issued by the regulatory authority. A supplemental type certificate (STC) is issued following a modification. The STC defines the product design change, states how the modification affects the existing type design, and lists serial numbers effectivity. It also identifies the certification basis listing specific regulatory compliance for the design change. Information contained in the certification basis is helpful for those applicants proposing subsequent product modifications and evaluating certification basis compatibility with other STC modifications. == Prototype == Initially, the applicant firm submits documents to their local aviation regulating body, detailing how the proposed design, i.e., the 'Type', would fulfill the airworthiness requirements. After investigations by the regulator, the final approval of such documents (after the required comments and amendments in order to fulfill the laws), becomes the basis of the certification. The firm follows it and draws a proposed timetable of actions required for certification tests. With the application, the regulations to be applied will usually be frozen for this application for a given amount of time in order to avoid a situation where the applicant would have to change the design as a result of changed regulation. An initial design sample known as a prototype is built. This refers to either the aircraft, the engines or the propeller, depending on the basis of the certification. For the purpose of illustration, the discussion shall be limited to the aircraft. Normally a few prototypes are built, each subject to different tests. The prototypes are first used for ground and system tests. One of the prototypes (known as the "static airframe") is subject to destructive testing, i.e., the prototype is subject to stress beyond normal and abnormal operations until destruction. The test-results are compared with initial submitted calculations to establish the ultimate structural strength. Other prototypes will undergo other systems tests until the satisfaction of the regulators. With all ground tests completed, prototypes are made ready for flight tests. The flight tests are flown by specially approved flight test pilots who will fly the prototypes to establish the ultimate flight limits which should be within the airworthiness rules. If a long range airliner is tested, the flight tests may cover the whole world. In parallel with aircraft testing, the applicant firm also draws up maintenance program to support continuous airworthiness after approval of the design. The program is drawn with inputs from tests results and also from initial customers' engineering departments. The proposed maintenance program is submitted to the regulators for comment and approval. After successful completion of ground and flight tests, along with an approved maintenance program, the prototype is approved, and the firm is granted the type certificate for the prototype (as understood that it should include all furnished equipment for its intended role). The legal term for the firm is now the "type certificate holder". Subsequently the prototype now serves as a template for aircraft production. Hence the aircraft rolling out of the factory should be identical to the prototype, and each given a serial number (a "series aircraft"). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Type certificate」の詳細全文を読む スポンサード リンク
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