Aircraft structural repairs are vital for maintaining the integrity and safety of the aircraft. When we consider the understanding of structural repairs, we can commonly come across some of the following considerations – note this is example of some conditions only and not by any means a complete detail.
We consider the nature of the repairs; for example, simple repairs could involve evaluating a dent, accompanied by some inspections and non-destructive testing (NDT). Such repairs might have minimal impact on the aircraft’s structure, but we would need to know the repair category and any additional considerations for continued airworthiness.
Complex Repairs might involve removing and replacing aircraft skin sections or cut outs often using doubler patches. Such repairs can typically have a more significant impact on the aircraft’s structure.
Repair Classifications are vital in the lease review as this gives us an indication as to the requirements associated with a repair, for example –
Category A: Minimal impact.
Category B: More significant impact might require additional inspections.
Refer to our post https://ialta.aero/repair-categories-aircraft-amp for more on categories.
You might also have a repair categorised by type such as the following:
Minor: No significant effect on aircraft’s characteristics and airworthiness.
Major: Everything beyond minor. It could impact airworthiness and the aircraft’s core characteristics.
Repair Source & Approvals:
Repairs are guided by OEM (Original Equipment Manufacturer) documentation, e.g., SRM (Structural Repair Manual) from Airbus or Boeing as examples of OEM.
Non-SRM repairs can originate from various sources: OEM or Part 21 approved companies also. Every repair must be approved, whether commonly by the OEM or an authorised Part 21 company.
Airbus RDAF – Repair Design Approval Sheet
As an example, we will consider an airbus non SRM repair; an Airbus RDAF (RDAF (Repair and Design Approval Form) also known as an RDAS (Repair Design Approval Sheet) prior to the new name, also known historically as a RAS, is often used for significant damage beyond SRM limits. This sheet is a formal communication from Airbus, providing permission for the repair. It’s essential to ensure the RDAF aligns with the specific Airbus model and that its guidelines are strictly followed.
Importance of Documentation: All repair documentation, whether a work order or associated with RDAF, should be meticulously maintained. In cases where a temporary RDAF is issued, a secondary RDAF might be provided later, clarifying repair impacts and instructions.
Importantly, an RDAF while current at time of issue can become invalid when damage occurs within the vicinity of the reported area for that RDAF – the RDAF would then need to be re-issued.
Structural repairs on aircraft involve rigorous standards and documentation to ensure airworthiness. Every repair, whether minor or major, plays a pivotal role in aircraft safety and operability.
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