A major change or repair is one that has 'an appreciable effect' on airworthiness or environmental characteristics.
The approval process for Major Change and Supplemental Type Certificate (STC) is essentially the same.
- The CAA will issue a Major Change Approval (per Part 21 Subpart D) if the applicant is the Type Certificate Holder (TCH) for the aircraft, engine or propeller,
and
- The CAA will issue an STC (per Part 21 Subpart E) for the approval of a major change from applicants other than the TCH.
A Major Repair Approval format is common to the TCH and non-TCH alike.
Modification of data and documentation such as the Aircraft Flight Manual and Operational Suitability Data will be processed as changes/repairs to the type design. There is no separate application.
Eligibility
Applicants for the CAA approval of a Major Change, Supplemental Type Certificate (STC) or Major Repair must hold an appropriate design organisation approval such as:
- Design Organisation Approval (DOA) in accordance with Part 21 Subpart J,
or
- Alternative Procedures to DOA (ADOA) as per 21.A.112B(b) for some simpler STCs,
or
- In the case of non-Part 21 aircraft (Annex 1) or engine/propeller, then a design organisation approval in accordance with BCAR A8-21.
In the case of a STC on ELA1 aircraft (European Light Aircraft as defined in EU Reg 748/2012), in the absence of an organisation approval, the applicant's capability may be shown through the Certification Programme as per 21.A.112B(c).
If DOA or ADOA is required, the scope of the certification project must be within the approved scope and Terms of Approval (TOA) of the DOA/ADOA. Applications are also accepted in cases when the certification project is simultaneously being used to demonstrate applicant competence for the issue of or extension to the scope or ToA of the DOA/DOA.
For further information on DOAs and ADOAs see our guidance on how to apply for a Part 21 Subpart J approval.
How to apply
An application is made using CAA Form SRG1726NR
Approval process
Applicant
responsible
for |
CAA
responsible
for |
Activity |
x |
|
Submit application on CAA Form SRG1726NR and provide the initial Certification Programme |
|
x |
Check eligibility of Applicant (to ensure that the project is within the DOA scope) |
x |
|
Provide Technical Familiarisation of the project (usually through the Certification Programme, but supplemented as necessary) |
x |
x |
Review the Certification Programme |
x |
x |
Agree the Certification Basis, Means of Compliance (MOC) and Level of Involvement (LOI) |
x |
|
Demonstrate compliance with airworthiness and environmental requirements |
|
x |
Determine compliance as per the agreed LOI and confirm with Applicant |
x |
|
Provide Declaration of Compliance |
|
x |
Issue Major Change/STC approval |