AppendixAppendix
Appendix H to GM 21.A.101Examples of documenting the proposed certification basis list
H.1 Example 1. H.1.1 This optional tool may be used to establish the applicable airworthiness and OSD certification specifications that will become part of the type-certification basis for airworthiness or OSD certification basis. For a significant change, the applicant must demonstrate compliance for the change and the area affected by the change with the certification specifications that were in effect at the date of application. However, in some cases earlier or later certification specifications can be used, as allowed in point 21.A.101. H.1.2 In order to efficiently determine and agree upon a certification basis with EASA, the following information is useful to understand the applicant’s position: H.1.2.1 The scope of the change. This includes a high-level description of the physical and functional changes and performance/functional characteristics, which are changed as a result of the physical or functional change, and the certification specifications for which compliance demonstration is required as a result of the change. H.1.2.2 The amendment level of all the applicable certification specifications at the date of application. H.1.2.3 The proposed certification basis, including amendment levels. H.1.2.4 Applicants who propose a certification basis that includes amendment levels earlier than what was in effect at the date of application should include the exception as outlined in point 21.A.101 and their justification if needed. H.1.3 Exceptions. H.1.3.1 Unrelated changes that are not significant (point 21.A.101(b)(1)). H.1.3.2 Not affected by the change (point 21.A.101(b)(2)). H.1.3.3 Compliance with the certification specification would not contribute materially to the level of safety (point 21.A.101(b)(3)). H.1.3.4 Compliance with the certification specification would be impractical (point 21.A.101(b)(3)). H.1.4 One easy way to document the proposed certification basis is using a tabular form as shown in Table below.
Table H-1. Tabular Form for Documenting a Proposed Certification Basis
| CS | Amendment Levels | Applicant Justification for Lower Amendment Level and Comments | Affected Area | ||
|---|---|---|---|---|---|
| Existing TCDS Amendment | Amendment at Date of Application | Proposed Amendment Level | |||
| Subpart A — General | |||||
| Subpart B — Flight | |||||
H.1.5 Best Practices. H.1.5.1 Account for all certification specifications, even if they are not applicable. H.1.5.2 Mark certification specifications that are not applicable as ‘N/A’. H.1.5.3 If more than one amendment level is used depending on the area of the product, list all areas and amendment levels at each area with proper justification. H.1.5.4 If the justification is long, provide the justification below the table and only place the certification specification reference and note in the comment field. H.1.5.5 Include airworthiness and OSD standards required by other EU regulations (e.g. Part-26) of affected areas. H.2 Example 2. Pages 129 through 135 of this Appendix contain another example for documenting a proposed certification basis.
Title of Design Change Product Name or Change to Type Certificate [XXXX] Proposed Certification Basis Pursuant to point 21.A.101
1.INTRODUCTION.
1.1 REFERENCE DOCUMENTS.
| Reference | Title |
|---|---|
| [1] Point 21.A.101 | Designation of applicable certification specifications and environmental protection requirements |
| [2] GM 21.A.101-1B | Establishing the Certification Basis of Changed Aeronautical Products |
| [3] XXXX | Application letter |
| [4] Type Certificate YYYY | Product type-certification basis |
| [5] Document ZZZZ | Certification plan |
| [6] |
<The above-referenced documents are examples. Each applicant should reference documents appropriate to their products and procedures.>
1.2 ACRONYMS.
| Acronym | Meaning |
|---|---|
| AFM | Aircraft Flight Manual |
| AMC | Acceptable Means of Compliance |
| CRI | Certification Review Item |
| ELOS | Equivalent Level of Safety |
| ESF | Equivalent Safety Finding |
| GM | Guidance Material |
| MOC | Means of Compliance |
| SC | Special Condition |
| TC | Type Certificate |
<This section constitutes a representative list of acronyms. Each applicant should provide an acronym list appropriate for their product and document.>
1.3 PURPOSE OF THE DOCUMENT. The purpose of this document is to propose the certification basis applicable to [Product Design Change] in accordance with point 21.A.101. <Note that this optional document is intended to be used for changes to type-certified products for which the change or a portion of the change is significant at the product level pursuant to 21.A.101. Not significant changes being accomplished concurrently with significant changes(s) would also be identified in this document.>
2.DESIGN DEFINITION.
2.1 BASELINE PRODUCT. The type design to be changed, which is also known as the ‘baseline product,’ is the Model Series___ (this should be a specific product configuration, such as a specific serial number or line number). The reference product certification basis is TCDS No. [XXXX], issued on [DATE].
2.2 DESIGN CHANGE AND BASELINE PRODUCT COMPARISON SUMMARY. <Example table where the product is an aeroplane. This is a representative set of data that may be provided by the applicant.>
| Specification | Model Series X | Model Series Y |
|---|---|---|
| Max Taxi Weight — MTW (lb) | A1 | A2 |
| Max Take-off Weight — MTOW (lb) | B1 | B2 |
| Max Landing Weight — MLW (lb) | C1 | C2 |
| Max Zero Fuel Weight — MZFW (lb) | D1 | D2 |
| Max Length (ft, in) | E1 | E2 |
| Max Height (ft, in) | F1 | F2 |
| Wing Span (ft, in) | G1 | G2 |
| Horizontal Tail Span (ft, in) | H1 | H2 |
| Fuel Capacity (gal) | I1 | I2 |
| Total Cargo Volume (ft3) | J1 | J2 |
| Max Passenger Limit — one class seating (occupants) | K1 | K2 |
| Engine Types | L1 & M1 | L2 |
| Maximum Engine Thrust | T1 | T2 |
2.3 DESCRIPTION OF DESIGN CHANGE, GROUPING AND CLASSIFICATION.
2.3.1 SIGNIFICANT CHANGE(S). <Describe here the stand-alone change(s) and/or change grouping(s) that are part of the proposed changed product and are proposed as significant. Include with each stand-alone change or change grouping the relevant accumulated change(s) and the applicable physical and/or functional effects. Note, the description should be detailed enough to identify why the change or change grouping is proposed as significant.> The following group of changes is proposed as significant based on [GM 21.A.101-1, Appendix A, ‘[Description of Change in Appendix A]] or [the general configuration is not retained, principles of construction are not retained, or assumptions for certification of the product to be changed do not remain valid]. Changes Related to [Title of Significant Change X]: [Title of High-Level Change C1] The areas of physical change are: [design change xx] [design change yy] [design change zz] The areas unchanged but affected by the change are: [affected area aaa] [affected area bbb] [affected area ccc] [Title of High-Level Change C2]…
2.3.2 UNRELATED NOT-SIGNIFICANT CHANGES. <Describe here the not significant stand-alone changes or change groupings that are part of the modification but are unrelated to any of the significant changes described in paragraph 2.3.1.> [Title of High-Level Change D1]. [Description]. <The description must be just detailed enough to serve its purpose, which is to identify why each of those changes is not significant and unrelated.> [Title of High-Level Change D2]. [Description]…
3.IDENTIFICATION OF APPLICABLE CERTIFICATION STANDARDS.
3.1 PROPOSED CERTIFICATION BASIS. Based on the effective application date, [date], under the provisions of 21.A.101, the applicable certification standards for the [Title of Design Change] are proposed as follows. The proposed certification basis includes exceptions to earlier amendments (reversions), deviations, special conditions, and equivalent (level of) safety findings.
3.1.1 Certification specifications effective at the date of application. Applicable certification specifications in effect on the date of the application are: <List the applicable parts and amendment levels here.> Example for large aeroplanes: A. Airworthiness: CS-25, CS-AWO. B. Operational Suitability Data:
CS-CCD,
CS-FCD, CS-MCSD (to be published),
CS-MMEL, CS-SIMD. C. Environmental Protection: CS-34, CS-36.
3.1.2 Point 21.A.101 exception rationale. The completed rationale for each does not contribute materially to the level of safety (DCMLS) or impracticality exception is provided in this section. Exception 1: … Exception 2: …
3.1.3 Optional certification standards Applicable certification specifications in effect on the date of the application are: <List the applicable parts and amendment levels here.> Example for large aeroplanes: CS 25.803, Emergency evacuation, Amendment 12, CS 25.1810, Emergency egress assisting means and escape routes, Amendment 17.
3.1.4 Design-related requirements from other aviation domains. Applicable certification specifications in effect on the date of the application are: <List the applicable parts and amendment levels here.> Example for large aeroplanes: CS-ACNS Communications, Navigation and Surveillance Initial Issue, dated 17 December 2013, Subpart D Sections 2/3, CS-26.
3.1.5 Proposed Special Conditions.
| Special Condition (or TBD) | Title | Effective Date (or TBD) |
|---|---|---|
3.1.6 Equivalent Safety Findings.
| ELOS Memo No (or TBD) | Title | Applicable Standard |
|---|---|---|
3.1.7 Deviations.
| Deviation No (or TBD) | Title | Applicable Standard | Date Issued (or TBD) |
|---|---|---|---|
3.1.8 Elect to comply
| Elect to Comply No (or TBD) | Title | Applicable Standard | Date Issued (or TBD) |
|---|---|---|---|
Proposed Certification Basis The certification basis is a complete extract from the applicable FAA 14 CFR part [A] and it references the certification basis [B]. Column [C] identifies the amendment level for the specific requirement on the date of application. The changed product’s certification basis is proposed in last column [D]. References to FAR sections and amendments are kept. Example for a Part 25 aeroplane:
| [A] Requirement | Title (or subparagraph) | [B] Existing Certification Basis Amendment Level | [C] Amendment Level on Application Date | [D] Proposed Amendment for Changed Product | Applicable Area | Notes |
|---|---|---|---|---|---|---|
| 25.25 | Weight limits | |||||
| 25-23 | 25-63 | 25-63 | Product | |||
| 25.33 | Propeller speed and pitch limits | |||||
| N/A | 25-72 | N/A | — | Not applicable to Changed Product (Jet Aircraft) | ||
| 25.1309(a) | Equipment, systems, and installations | |||||
| 25-41 | 15-123 | 25-123 | Changed and Affected Areas | |||
| 25-41 | 25-123 | 25-41 | Exception — Not Affected | See example 1 in section 3.1.2 | ||
| 25.1703 | Function and installation: EWIS | |||||
| N/A | 25-124 | N/A | Exception — Product | See example 2 in section 3.2.1 | ||
APPENDIX · Appendix H to GM 21.A.101 — Regulation (EU) No 748/2012 · ED Decision 2017/024/R · Initial Airworthiness Easy Access Rules · EAR revision 27 Nov 2025