UK CAA – EASA Validation of Design Certificates Review

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Overview by Sofema Online (SOL)

Validation of Design Certificates (Typically None Minor)

The Technical Agents have established two paths for validation:

» Streamlined validation; or

» Validation in line with the level of involvement principles.

Streamlined Validation

This validation path is applicable:

» To significant supplemental type certificates and approvals for significant major changes issued by the Technical Agent of the European Union as Certificating Authority and

» When decided by both Technical Agents on a case-by-case basis:

o   Supplemental Type Certificates,
o   Approvals for Major Changes,
o   Major Repairs and
o   Technical Standard Order Authorisations issued by UK CAA

Note: The significant/non-significant distinction is made by the Certificating Authority in accordance with the criteria outlined in EASA Part 21.A.101 and UK Part 21.A.101, respectively, and interpreted in accordance with the applicable rules and procedures of the Certificating Authority.

Validation in line with the level of involvement principles

» Design certificates and restricted type certificates issued by the European Union or United Kingdom Technical Agents as Certificating Authority); and

» Design certificates referred to in Article 10(4), Annex 30 of the Agreement (supplemental type certificates, approvals for major changes, major repairs and technical standard order authorisations issued by the Technical Agent of the United Kingdom or by an approved organisation under laws and regulations of the United Kingdom), unless otherwise decided by the Technical Agents on a case-by-case basis.

Data Package

» The data package will be submitted to the appropriate VA office.

» The CA will check that the data package contains adequate information.

Note: For certain projects, some elements of the data package will not be available at the time of application; the data package for such projects will include all known data at the time of application.

This does not prevent the validation process from being started and missing information will be provided to the VA as it becomes available during the course of the project.

» A validation data package is comprised of:

o   A description of the product.
o   If the application concerns a TC:
o   The descriptive data provided for in UK Part 21.A.15 for applications to the UK CAA or EASA Part 21.A.15 for applications to EASA;
o    A list of any applicable CA mandatory continuing airworthiness information (MCAI) such as ADs;
o   A statement confirming that changes to correct any unsafe condition identified in the MCAI have been incorporated into the type design presented for validation; and
o   A copy of any approved manuals and approved instructions for continued airworthiness (ICA).
o   If the application concerns a design change, including an STC:

- A high-level description of the change, together with the make and model of the product being changed;
- If affected, a copy of changes to the Airworthiness Limitations Section (ALS) of the ICA;
- If affected, a copy of changes to other Operating Limitations (e.g. Aircraft Flight Manual); and
- If affected, of copy of changes to the OSD.
- The VA needs to be aware of any such changes to ensure it is able to release updated information, or to perform any necessary mandatory airworthiness activity as required by its system, or to address crew-training requirements to support the operational introduction of the design change.
- Any additional information the VA needs to fulfill such responsibilities will be requested by the VA within the timeframe specified

Additional Comments

The CA’s airworthiness requirements and the VA’s Significant Standard Differences (SSDs), special conditions, equivalent safety findings, and deviations the VA has prescribed to enable the same level of safety as the VA’s airworthiness requirements to be achieved; and

The CA’s noise, fuel venting, and emissions requirements, plus any other requirements prescribed by the VA to provide noise, fuel venting, and emissions requirements equivalent to those provided in the applicable VA standards.

In the case of technical standard order authorisation, the applicable ETSO with the applicable limitations and deviations compensated for by factors or design features providing an equivalent level of safety. The statement should also confirm the non-interference of any non-ETSO functions when present.  

When affected, the detailed environmental characteristics of the product.

Streamlined validation process

The streamlined validation process is where validation is limited to a VA’s technical familiarisation with the Design Certificate to be validated.

» There is no involvement of the VA in the showing/ findings of compliance activities and once the technical familiarisation is complete, the VA will issue a validated Design Certificate based on the corresponding CA Design Certificate and the statement of compliance from the CA to the VA.

» Streamlined validation process projects are managed as sequential projects, in which the CA submits a validation application to the VA after the CA has completed its certification programme.

o Where there is an urgent operational need to complete the validation process for a design change that could be subject to streamlined validation, the technical validation procedure may offer the possibility of a concurrent validation exercise.

Next Steps

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