Under the present rules, how can a production or maintenance organisation continue to use tools or equipment even if their calibration/periodical check cannot be carried out before the due date?
1. Purpose of the document
Considering the restrictions of movement of people or the temporary lack of access to certain facilities and/or services due to the COVID-19 crisis, which may have as a result that production and maintenance organisations are not able to get calibration/periodical checks of their tools and equipment carried out before the due date, the Agency was requested to provide additional guidance to the competent authorities to facilitate a simpler process of approving changes to the applicable organisation’s procedures, and to ensure as much as possible the continuation of production and maintenance organisation activities during this period, in compliance with the applicable requirements.
2. Description of the issue
In accordance with:
- For Part 21, Subpart F: points 21.A.125A and 21.A.126(a)(3)/GM No 2 to 21.A.126(a)(3);
- For Part 21, Subpart G: points 21.A.139(b)1.(vii), 21.A.143(a)(11) and 21.A.145(a)/GM 21.A.145(a); and
- For Part-M, Subpart F; Part-CAO and Part-145: as applicable, points M.A.604(a)7, M.A.608(b), CAO.A.050(b), CAO.A.025(a)(10), 145.A.40(b), 145.A.70(a)12., M.A.402(d) and ML.402(b)(4),
the production or maintenance organisation shall ensure, by complying with adequate procedures included in its exposition or manual, that all tools and equipment, as appropriate, are controlled and calibrated/periodically checked according to an officially recognised standard at a frequency to ensure serviceability and accuracy.
When such a procedure includes a recurrent calibration/periodical check of tools or equipment, it is possible that, due to the COVID-19 crisis, the procedure cannot be complied with because a recurring calibration/periodical check cannot be carried out before the specified due date. In such a case, a temporary change (direct or indirect approved or concessions) to the procedure may be acceptable in order to allow continuation of the activities in compliance with the rules.
In accordance with:
- For Part 21, Subpart F: points 21.A.125A and 21.B.140;
- For Part 21, Subpart G: points 21.A.143, 21.A.147 and 21.B.240;
- For Part-M, Subpart F: points M.A.604, M.A.617 and M.B.606;
- For Part-CAO: points CAO.A.025, CAO.A.105 and CAO.B.065; and
- For Part-145: points 145.A70, 145.A.85 and 145.B.35,
the competent authority may approve a temporary change to the applicable organisation’s procedure to allow an extension of the period at the end of which the calibration/periodical check of the tool or equipment is due.
3. Considerations for the competent authority (CA) and the organisations
The decision of the competent authority on the approval of such a temporary change should be taken based on a risk analysis performed by the organisation. The risk analysis shall consider the previous performance and reliability of the tool or equipment, previous calibration and periodical checks results and possible additional mitigating measures (like using tools from other organisations for critical applications).
Few considerations for the risk analysis may be, but are not limited to the following:
- when the normal calibration/check period is ≤ 12 months the extension of the calibration and/or periodical check can be up to a maximum of 10 % of the normal calibration/check;
- when the calibration/check period is > 12 months the extension of the calibration can be 10 % of the normal calibration/check period up to a maximum of 3 months;
- the risk associated to the use of the tool or equipment for the specific task in relation to ensuring conformity with the approved data or continuing airworthiness of the aircraft or components is not determined critical;
- the tool or equipment is inspected before use and no damage or corrosion is identified;
- the tool or equipment was recently used (e.g. within the 3 months preceding the calibration or periodical check due date);
- no deficiency with the use of this tool or equipment has been reported since the last calibration or periodical check;
- the last two calibration results or last periodical checks are not showing any possible issues (e.g.: drift in the value, value very close to the acceptable limit, etc.) that can endanger the result of the activity performed.
If the risk associated to the use of the tool or equipment for the specific task is identified as critical, the organisation shall receive the tool or equipment manufacturer extension acceptance, and shall take additional measures to verify and ensure the correct production / maintenance results, such as:
verification of the tool or equipment serviceability by comparison with another tool/equipment duly calibrated/periodically checked, and/or
verification of the measurement/test/job-result by other acceptable means.
The tools or equipment with extended calibration or maintenance interval, should be recorded in a dedicated form, allowing tracking the tasks performed. If the tool / equipment fails during next regular calibration / inspection, the completed tasks may require to be verified / performed again.