21L.A.25 Demonstration of compliance

COMPLIANCE DOCUMENTATION

(a)Compliance documentation comprises one or more test or inspection programmes/plans, reports, drawings, design data, specifications, calculations, analyses, etc., and provides a record of the means by which compliance with the applicable type-certification basis and environmental protection requirements is demonstrated.

(b)Each compliance document should normally contain: the reference of the certification specifications, special conditions or environmental protection requirements addressed by the document; substantiation data demonstrating compliance (except test or inspection programmes/plans); a statement by the applicant declaring that the document provides the proof of compliance for which it has been created; and the appropriate authorised signature.

(c)Each compliance document should be unequivocally identified by its reference and issue date. The various issues of a document should be controlled and comply with point 21L.A.7 ‘Record-keeping’.

INSPECTIONS AND TESTS Proposed type design: this term defines the type design (or the portion of the type design) as it is determined at the time when the testing and inspections are performed. Verification document (also known as ‘statement of conformity’): before each testing and inspection the verification document must confirm that the test specimen conforms with the proposed type design and that the test and measuring equipment is adequate for the test and that the sensors and measuring system are appropriately calibrated. Conformity of the test specimen: the documented verification is intended to ensure that the manufactured test specimen, even in the presence of non-conformities, adequately represents the proposed type design. Possible types of non-conformity may be the following: Non-conformity between the design of the test specimen and the proposed type design at the time of the test. These are typically identified in the early stage of the testing and inspection planning, and should be addressed as early as possible (e.g. in the test plan). There may be several reasons for such a non-conformity: to account for interfaces with the test equipment, to conservatively cover several existing or future design configurations, etc. Non-conformity between the manufactured test specimen and the design of the test specimen. Such a non-conformity may be the result of the manufacturing of the test specimen. While it is convenient to define any possible non-conformity as early as possible, the applicant does not need to make the distinction between the two types of non-conformity above as long as they are explicitly addressed, justified in the verification document or by cross reference to the test plan or other documents. However, testing for the demonstration compliance with the applicable environmental protection requirements should be conducted in the final design of the product. Type certification is typically an iterative process in which the design is under continuous evolution. If the type design evolves after the time of the testing and inspections, then the final type design should be checked against the proposed type design (as it was at the time of the testing and inspections), and the differences (if any) should be analysed to ensure that the testing and inspection results are representative of the final configuration. However, such changes made to the type design may lead to the invalidation of the testing and inspection results, and the need to repeat the testing and inspections. It is recommended that the design organisation should have a thorough configuration management process to track the evolving type design. Conformity of test and measuring equipment: the configuration of the test and measuring equipment should be defined in the test plan and include the following: definition/design of the test equipment (relevant tools, mechanical parts, electronic components used to execute the test); and definition of the measuring equipment: type/model of sensors, together with their technical characteristics; position and orientation of exciters and sensors; and electronic measuring equipment (in some cases, this may also include the acquisition and post-processing of data). The configuration of the test and measuring equipment should be defined and controlled through certification test plans and supporting documentation, according to the design assurance system, if applicable. The test plan should also include the following elements: the test cases, methods, and procedures for test execution; the pass–fail criteria; and pre-, during- and post-test inspections. The verification document should confirm that the test and measuring equipment conforms to its purpose, and that the sensors and measuring system are appropriately calibrated. Any non-conformity should be assessed, and it should be justified that it will not compromise the test purpose and results. This can be done either in the verification document or by cross reference to other documents (test minutes of meetings, test notes, etc.). Use of the term ‘adequate’: the test specimen, as well as the test and measuring equipment, is considered ‘adequate’ as long as the test execution on the manufactured test specimen (including any non-conformity) and the use of the installed test set-up does not compromise the test purpose and results (for example, by providing better performance than the proposed type design, or masking any potential failure mode or behaviour). Changes that affect the validity of the verification document: if changes need to be introduced to the test specimen or to the test and measuring equipment after the verification is documented (and before the test is undertaken), then the verification document must be updated. The updated verification document must be made available to EASA before the test if EASA has informed the applicant that it will witness or carry out the tests or inspections. Development versus certification tests: sometimes, tests of specimens that conform to a preliminary design, but are not intended for certification (known as development tests), are performed as part of a risk control strategy and to develop knowledge of a subject. Problems and failures found during development are part of the process of increasing the understanding of the design, including its failure modes and the potential for optimisation. Such development tests do not need to meet the requirements of point 21L.A.25(c). Any planned test event should be classified in advance as either a development test or a certification test. Tests that support the compliance demonstration should be classified as certification tests. It is acceptable for a development test to finally form part of the compliance demonstration, and it may be declared afterwards to be a certification test as long as it meets the requirements of point 21L.A.25(c). For this reason, it is important to keep the configuration of such tests under control. If the test specimen used for a certification test has already undergone a series of previous tests that may affect or ultimately invalidate its acceptance as required by point 21L.A.25(c), this aspect should be considered when documenting the verification, and specific analyses or inspections may be required. Because of the above aspects, EASA advises applicants to inform it if they intend to conduct a campaign of development tests that may eventually be used as certification tests to establish whether EASA would wish to witness the test.

FLIGHT TESTING Detailed material on flight testing for compliance demonstration is included in the applicable CSs and GM. Information on flight testing for compliance demonstration with the environmental protection requirements especially in terms of aircraft noise may be found in Annex 16 to the Chicago Convention and in ICAO Doc 9501 ‘Environmental Technical Manual’. The objective of the period of operation in the final configuration is to expose the aircraft to the variety of uses, including training, that are likely to occur when in routine service to provide an assurance that it performs its intended functions to the standard required for certification and should continue to do so in service. The flight tests should include a range of representative ambient operating conditions and airfields. This period of operation may fully overlap with the compliance-demonstration flight testing if it can be demonstrated that the above criteria are met. The duration of this period as well as the approach selected (i.e. use of compliance-demonstration flights or extending the period of operation) should be proposed in the compliance-demonstration plan. The flight testing should cover both routine operations and some simulation of abnormal conditions. The details of the programme should be agreed with EASA prior to commencement of the testing. It may be possible to combine this testing with any testing required to demonstrate compliance with the applicable CSs. This will be agreed on a case-by-case basis with EASA. A substantial proportion of the flying should be on a single aircraft (and, if applicable, a combination of engine and propeller). The flying should be carried out to a continuous schedule on an aircraft that is very close to the final type design, operated as though it were in service and should include a range of representative ambient operating conditions and airfields.

REVIEW OF DATA AND INFORMATION RELATED TO THE DEMONSTRATION OF COMPLIANCE Availability of compliance data (see point 21L.A.25(e)): data and information required to be provided by the applicant should be made available to EASA in a reliable and efficient way as agreed by EASA.

TESTS AND INSPECTIONS The applicant should inform EASA sufficiently in advance about the execution of tests and inspections that:

1.are used for compliance-demonstration purposes; and

2.have been identified as being of particular interest to EASA during the review and approval of the compliance-demonstration plan in order to permit EASA the opportunity to witness or carry out these inspections or tests. The applicant may propose to EASA to witness or carry out flight or other tests of particular aspects of the product during its development and before the type design is fully defined. However, in case of flight tests, the applicant should perform the tests before EASA witnesses or performs them to ensure that no features of the product preclude the safe conduct of the evaluation requested. The Agency may require any such tests to be repeated once the type design is fully defined to ensure that subsequent changes have not adversely affected the conclusions from any earlier evaluation. A verification document as per point 21L.A.25(c) is required for the above tests.

PHYSICAL INSPECTION OF THE FIRST ARTICLE Note: The applicant should be prepared for any additional investigations as notified by EASA according to point 21L.B.46(d).

1.Purpose The purposes of the first-article inspection (of the article that is in conformance with the proposed type design for certification) prior to the issuance of the type certificate for a particular aircraft, propeller or engine design are the following: a. for EASA to verify completion of the demonstration-of-compliance activities conducted by the applicant under point 21L.A.25 and in accordance with the approved compliance-demonstration plan; b. for EASA to verify1 that the type design complies with the type-certification basis and the applicable environmental protection requirements; c. In case the applicant is a declared design organisation, for EASA to conduct a further oversight visit in accordance with point 21L.B.183(b) of Subpart J in order to ensure that the applicant is able to discharge its obligations. 1 The verification of compliance is limited to the scope of the activities that can be conducted under point 2 and the elements of the design that are selected for review based upon a risk-based approach to compliance.

2.Methodology and evidence The first-article inspection will be conducted by EASA at an appropriate location(s) selected by the applicant for a type certificate. This (these) location(s) should: include the physical location of the aircraft, engine or propeller for which a type certificate has been requested; and be in the principal place of business (which in accordance with Article 8(2) of Regulation (EU) No 748/2012 must be in an EU Member State). Note: The principal place of business is defined as follows: ‘The head office or registered office of the organisation within which the principal financial functions and operational control of the activities referred to in this Regulation are exercised.’ The Agency will conduct a physical inspection of the aircraft, engine or propeller for which a type certificate has been requested. This inspection, along with any other activity that EASA deems necessary (see point 21L.A.25(e)), should ensure that the objectives mentioned in point 1 are met. The applicant for a type certificate should make the following arrangements to support the first-article inspection: a. prepare the aircraft engine, propeller, systems or components for live testing (including flight testing) upon EASA’s request; b. make available the final version of the compliance-demonstration plan; c. make available the declaration of compliance for the product (aircraft, engine and/or propeller); d. provide access to the supporting compliance documentation and test reports; e. provide access to key design and production personnel; f. make available any design processes and procedures that were used. When the applicant has selected to use flight testing to demonstrate compliance (see MC6 in Appendix A to AMC1 21L.A.24(b)), EASA may decide to conduct flight testing to verify compliance. This flight testing will be performed according to a plan proposed by the applicant prior to the first-article inspection and agreed by EASA. The above list of additional sources of evidence is not exhaustive. It is possible that during the first-article inspection, EASA may discover evidence that: a. the design is not in compliance with the type-certification basis or the applicable environmental protection requirements (this could be due to the applicant misinterpreting or misunderstanding the applicable design requirements); b. the applicant has not fulfilled its design obligations as a declared design organisation; c. there are shortfalls in the applicant’s design management system (in accordance with point 21.A.239 or point 21L.A.174) that result in a non-compliance or loss of control of the design. If such evidence is discovered, the applicant should support EASA in conducting a more in-depth investigation into the compliance documentation and/or the design practices of the design organisation. The purpose of this in-depth investigation should be to determine whether or not compliance was demonstrated, the root cause and the corrective actions. This investigation should also serve to prevent a reoccurrence of the issue.

3.Aircraft condition and configuration The aircraft, engine or propeller presented to EASA should be in the final configuration for which a type certificate has been requested and the compliance demonstration has been declared. The applicant may arrange visits with EASA prior to the declaration of compliance, in accordance with point 21L.A.25(f) (for example, for noise testing). Any differences between the configuration presented to EASA for the first-article inspection and the final configuration in the declaration of compliance (in accordance with point 21L.A.25(f)) should be justified by the applicant and may, therefore, depending upon their criticality, be subject to more focused scrutiny during the first-article inspection. It is possible that some differences from the final configuration may delay the issuance of the type certificate.

4.Findings and resolution In the process of the activities mentioned in point 2, EASA will raise an appropriate finding or observation against the aircraft or declared design organisation if a non-compliance is discovered. Findings of non-compliance should be resolved by the applicant before the type certificate is issued.

5.Duration and schedule The first-article inspection may be a single visit or multiple visits depending on the complexity of the design. For example, EASA may wish to witness or participate to compliance-demonstration testing (for example, noise testing) prior to the first-article inspection. The applicant should coordinate with the competent authority so that the first-article-inspection activities conducted under point 21L.B.143(b) are conducted as far as practicable at the same time as first-article-inspection activities conducted under point 21L.B.46(c).

DECLARATION OF COMPLIANCE All compliance-demonstration activities conducted in accordance with the compliance-demonstration plan, including all the testing and inspections conducted in accordance with point 21L.A.25(c) and all flight testing conducted in accordance with point 21L.A.25(d) and those necessary to determine compliance with the applicable environmental protection requirements should be completed before the issuance of the final declaration of compliance. ‘No feature or characteristic’ that may make the product unsafe in point 21L.A.25(f)(2) means the following: while every effort is made to address in the applicable certification basis all the risks to product safety that may be caused by the product, experience shows that safety-related events may occur with products in service, even though compliance with the certification basis is fully demonstrated. One of the reasons may be that some existing risks are not properly addressed in the certification basis. Therefore, the applicant should declare that it has not identified any such features or characteristics. ‘No feature or characteristic’ that may make the product environmentally incompatible (point 21L.A.25(f)(2)): It is assumed that environmental compatibility is demonstrated when the product complies with the applicable environmental protection requirements. Therefore, the applicant, when declaring that the aircraft complies with the applicable environmental protection requirements under point 21L.A.25(f)(1), shall also declare that they have not identified any such feature or characteristic.