Can We Manage Components Off-Wing without a “C” Rating Approval – when the inspection is included in the AMM (Small company)
A Short Answer is a qualified yes – However to Note it is nothing to do with Company Size
The question of whether an organization can manage components off-wing without a Category C (Component) rating is a frequent point of discussion in EASA Part-145 and Part-CAO environments.
Under Regulation (EU) No 1321/2014, the short answer is indeed a qualified yes, but the regulatory “safety net” that allows this is very specific.
- It relies on the distinction between maintaining a component as part of the aircraft versus maintaining it as a standalone asset.
The Regulatory Basis: The “A” Rating Privilege
According to AMC 145.A.42(b)(ii) (and similar provisions in Part-CAO), an organization with an Aircraft (A) rating may maintain a component while it is temporarily removed for any of the following reasons:
- To improve access to other parts of the aircraft.
- To perform maintenance on the component itself, provided the instructions for that maintenance are found in the Aircraft Maintenance Manual (AMM).
The “Same Aircraft” Rule
The critical regulatory “hook” is the intent. The component is treated as an extension of the aircraft. As long as the component is intended to be reinstalled on the same aircraft before the final Certificate of Release to Service (CRS) is issued, the “A” rating is sufficient.
AMM vs. CMM: The Defining Line
The scope of work is dictated by the data source, not just the location of the component.
- AMM (Aircraft Maintenance Manual): If the manufacturer includes a procedure in the AMM (e.g., “Clean and inspect battery” or “Test ELT”), an “A” rated organization can do this on a bench.
- CMM (Component Maintenance Manual): Generally, if the work requires instructions, specialized tools, or test benches defined strictly in the CMM, it falls into the realm of a “C” rating.
Key Takeaway: If you are using the CMM to certify the work, you are acting as a Component Workshop, which requires a “C” rating and the issuance of an EASA Form 1.
The Challenge: When the Aircraft Leaves
The scenario becomes complex if the aircraft is ready to go, but the component is still on the bench (perhaps due to a discovered defect or a delay in parts).
If you have a “C” Rating:
The workshop can finish the work, issue an EASA Form 1, and return the component to stores as a “serviceable” part available for any aircraft in the fleet.
If you DO NOT have a “C” Rating:
You cannot issue an EASA Form 1. This leaves the component in a “regulatory limbo.” To manage this, the organization must have a robust MOE (Maintenance Organization Exposition) procedure for:
- Removal of Serviceable Components: If a component is removed from an aircraft in a serviceable condition (and was serviceable when fitted), it can be tagged as such, provided the history is known.
- Tagging and Segregation: If the component was removed for maintenance and that maintenance wasn’t completed before the aircraft departed, it remains unserviceable until a “C” rated shop certifies it.
Why Company Size is Irrelevant
The regulation does not care if you are a “one-man band” or a global MRO.
- Safety is Standardized: The risk of a faulty component is the same regardless of company size.
- Procedures over Personnel: A small company can perform off-wing tasks if their MOE/CAE defines the process and they have the approved tools/facilities listed in the AMM.
The Pre-Conditions for “Serviceable Removal”
- The Source: The component must have been removed from an EU-registered aircraft.
- The Condition: The component was in a serviceable condition while fitted to the aircraft. You cannot “repair” a broken part and use this process.
- The Data: You must use the Aircraft Maintenance Manual (AMM) for the removal and any subsequent “bench” testing/inspection.
The Verification Process (The “Investigation”)
The certifying staff (B1/B2/B3) must verify the component’s status to ensure it is fit for release. You need to document:
- Traceability: Which aircraft (Registration and MSN) did it come from?
- Hours/Cycles: What are the total times and, if applicable, the times since new (TSN) or since overhaul (TSO)?
- AD/SB Status: Are there any outstanding Airworthiness Directives or mandatory Service Bulletins?
- Occurrence History: Confirm the aircraft has not been involved in an accident, incident, fire, or flood (which would render the part “unsalvageable” without deeper shop inspection).
Completing the EASA Form 1
When an “A” rated organization issues a Form 1 for a removed serviceable component, the form acts as a “Statement of Reality” regarding its condition and history.
Key Blocks to Fill:
- Block 11 (Status/Work): Enter “Serviceable”.
- Block 12 (Remarks): This is the most critical section. It must contain a specific set of declarations. If this block is incomplete, the Form 1 is often rejected by other MROs.
Mandatory Information for Block 12:
- “Serviceable component removed from an aircraft.”
- Aircraft Details: Registration, Type, Serial Number, and total flight hours/cycles of the aircraft at removal.
- Component Details: Total flight hours/cycles/landings (as applicable).
- Maintenance Data: Reference the AMM chapter/section used for removal and inspection (e.g., “Removed and inspected I.A.W. AMM 24-20-00”).
- AD/SB Status: State that all applicable ADs are current or list the last one complied with.
- Non-Incident Statement: “The component was not removed from an aircraft involved in an accident or incident.”
- Block 14a (Release to Service): Check the box for 145.A.50 Release to Service.
- Note: You are certifying that the work (the removal and inspection) was done per Part-145 and the part is “ready for fly.”
Supporting Paperwork (The “Back-to-Birth” File)
The Form 1 does not stand alone. To satisfy an auditor or a future buyer, you should staple the following to the Form 1:
- The Removal Work Order: The actual job card signed by the mechanic who removed the part.
- The Aircraft Logbook Entry: A copy of the page showing the component removal and the aircraft’s total time.
- The “Birth Certificate”: If available, the original Form 1 that was used when the part was first installed on that aircraft.
Next Steps
Join Sofema for a free EASA Compliance Auditors Masterclass on 20 May, led by industry expert and CEO, Steven Bentley. This session will explore the evolving auditor role under Part-CAMO and SMS, focusing on risk-based auditing and modern competencies. Register here as places are limited.
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Tags:
Airworthiness Directives, EASA Part 145, Part CAO, sasblogs, EASA Form 1, Sofema Online (SOL), Sofema Aviation Services (SAS), Component Maintenance, Aviation Compliance
