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Aircraft certificate of release to service

M.A.801

M.A.801(a) Definition CRS

(a) Except for aircraft released to service by a maintenance organisation approved in accordance with Annex II (Part-145), the CRS shall be issued in accordance with this Subpart.

M.A.801(b) CRS issuance

(b) No aircraft shall be released to service unless a CRS is issued when all maintenance tasks ordered have been properly carried out. The CRS shall be issued by an authorised certifying staff of the maintenance organisation approved in accordance with Subpart F of this Annex or with Annex Vd (Part-CAO), except for maintenance tasks other than complex maintenance tasks listed in Appendix VII to this Annex where the CRS is issued, alternatively by:

1. independent certifying staff acting in accordance with the requirements laid down in Article 5 of this Regulation;
2. the pilot-owner acting in accordance with point M.A.803 of this Annex.

AMC M.A.801(b) CRS issuance

A certificate of release to service is necessary before flight, at the completion of any defect rectification, whilst the aircraft operates a flight between scheduled maintenance checks.

M.A.801(c) One-off authorization maintenance

(c) By derogation from point (b), in case of unforeseen situations, when an aircraft is grounded at a location where no maintenance organisation approved in accordance with this Annex, Annex II (Part-145) or Annex Vd (Part-CAO) and no independent certifying staff are available, the owner may authorise any person, with no less than 3 years of appropriate maintenance experience and holding either a valid ICAO Annex 1 compliant maintenance license for the aircraft type requiring certification or a certifying staff authorisation valid for the work requiring certification issued by an ICAO Annex 6 approved maintenance organisation to maintain the aircraft in accordance with the standards set out in Subpart D of this Annex and release it to service. In that case, the owner shall:

1. obtain and keep in the aircraft records specifying details of the maintenance carried out and of the qualifications of the person issuing the CRS;

2. ensure that any such maintenance is later on verified and a new CRS is issued by an appropriately authorised person referred to in point (b) or an organisation approved in accordance with Subpart F of this Annex, Annex II (Part-145) or Annex Vd (Part-CAO), at the earliest opportunity and in any case within 7 calendar days from the issuance of a CRS by the person authorised by the owner;

3. notify the organisation responsible for the continuing airworthiness management of the aircraft, when contracted, or the competent authority in the absence of such a contract, within 7 days from the issuance of such authorisation.

AMC M.A.801(c) Aircraft grounded at other locations- Qualifications

1. ‘3 years of appropriate maintenance experience’ means 3 years working in an aircraft maintenance environment on at least some of the aircraft type systems corresponding to the aircraft endorsed on the aircraft maintenance license or on the certifying staff authorisation that the person holds.

2. ‘Holding the proper qualifications’ means holding either:
(a) a valid ICAO Annex 1 compliant maintenance license for the aircraft type requiring certification, or;
(b) a certifying staff authorisation valid for the work requiring certification, issued by an ICAO Annex 6 approved maintenance organisation.

3. A release in accordance with this paragraph does not affect the controlled environment, in accordance with point (b) of M.A.901, of the aircraft as long as the M.A.801(c)2 recheck and release has been carried out by an approved maintenance organisation.

M.A.801(d) Assistance during maintenance

(d) In case of a release to service in accordance with point (b)(2), the certifying staff may be assisted in performing the maintenance tasks by one or more persons subject to his or her direct and continuous control.

M.A.801(e) CRS contents

(e) A CRS shall contain at least:

1. basic details of the maintenance carried out;
2. the date on which the maintenance was completed;
3. the identity of the organisation or person issuing the CRS, including, alternatively:

(i) the approval reference of the maintenance organisation and the certifying staff issuing the CRS;
(ii) in the case referred to in point (b)(2), the identity and, where applicable, the licence number of the certifying staff issuing the CRS;

4. the limitations to airworthiness or operations, if any.

AMC M.A.801(e) CRS contents

1. The aircraft certificate of release to service should contain the following statement:

(a) ‘Certifies that the work specified except as otherwise specified was carried out in accordance with Part-M and in respect to that work the aircraft is considered ready for release to service’.
(b) For a Pilot-owner a certificate of release to service should contain the following statement:
‘Certifies that the limited pilot-owner maintenance specified except as otherwise specified was carried out in accordance with Part-M and in respect to that work the aircraft is considered ready for release to service’.

2. The certificate of release to service should relate to the task specified in the manufacturer’s or operator’s instruction or the aircraft maintenance programme which itself may cross-refer to a manufacturer’s/operator’s instruction in a maintenance manual, service bulletin etc.

3. The date such maintenance was carried out should include when the maintenance took place relative to any life or overhaul limitation in terms of date/flying hours/cycles/ landings etc., as appropriate.

4. When extensive maintenance has been carried out, it is acceptable for the certificate of release to service to summarise the maintenance so long as there is a unique cross-reference to the work-pack containing full details of maintenance carried out. Dimensional information should be retained in the work-pack record.

5. The person issuing the certificate of release to service should use his normal signature except in the case where a computer release to service system is used. In this latter case the competent authority will need to be satisfied that only the particular person can electronically issue the release to service. One such method of compliance is the use of a magnetic or optical personal card in conjunction with a personal identity number (PIN) known only to the individual, which is keyed into the computer. A certification stamp is optional.

6. At the completion of all maintenance, owners, certifying staff, operators and maintenance organisations should ensure they have a clear, concise, legible record of the work performed.

7. In the case of an M.A.801(b)1 release to service, certifying staff should retain all records necessary to prove that all requirements have been met for the issuance of a certificate of release to service.

M.A.801(f) Incomplete CRS

(f) By derogation from point (b) and notwithstanding point (g), when the required maintenance cannot be completed, a CRS may be issued with the approved aircraft limitations. In that case, the certificate shall indicate that the maintenance could not be completed, as well as indicate any applicable airworthiness or operations limitations, as part of the information required by point (e)(4).

AMC M.A.801(f) Incomplete maintenance

1. Being unable to establish full compliance with sub-paragraph M.A.801(b) means that the maintenance required by the aircraft owner, CAO or CAMO could not be completed due either to running out of available aircraft maintenance downtime or because the maintenance data requires a flight to be performed as part of the maintenance, as described in paragraph 4.

2. The aircraft owner, CAO or CAMO is responsible for ensuring that all required maintenance has been carried out before flight. Therefore, an aircraft owner, CAO or CAMO should be informed and agree to the deferment of full compliance with M.A.801(b). The certificate of release to service may then be issued subject to details of the deferment, including the aircraft owner, CAO or CAMO authorisation, being endorsed on the certificate.

3. If a CRS is issued with incomplete maintenance a record should be kept stating what action the mechanic, supervisor and certifying staff should take to bring the matter to the attention of the relevant aircraft owner, CAO or CAMO so that the issue may be discussed and resolved with the aircraft owner, CAO or CAMO.

4. Certain maintenance data issued by the design approval holder (e.g. aircraft maintenance manual (AMM)) require that a maintenance task be performed in flight as a necessary condition to complete the maintenance ordered. Within the aircraft limitations, the person authorised to certify the maintenance per M.A.801 should release the incomplete maintenance before this flight. GM M.A.301(i) describes the relations with the aircraft operator, which retains the responsibility for the MCF. After performing the flight and any additional maintenance necessary to complete the maintenance ordered, a certificate of release to service should be issued in accordance with M.A.801.

M.A.801(g) CRS issuance

(g) A CRS shall not be issued in the case of any known non-compliance which endangers flight safety.

AMC M.A.801(g) Definition

‘Endangers flight safety’ means any instance where safe operation could not be assured or which could lead to an unsafe condition. It typically includes, but is not limited to, significant cracking, deformation, corrosion or failure of primary structure, any evidence of burning, electrical arcing, significant hydraulic fluid or fuel leakage and any emergency system or total system failure. An AD overdue for compliance is also considered a hazard to flight safety.

Can an independent certifying staff maintain non-complex motor-powered aircraft used by commercial ATO or commercial DTO?

No, non-complex motor-powered aircraft used by commercial ATO or commercial DTO cannot be maintained by independent certifying staff because in accordance with M.A.201(h) or ML.A.201(e)(2), these aircraft  require maintenance release by an approved maintenance organisation (Part-CAO with maintenance privilege, Part-M Subpart F or Part-145).

Note: ‘GM1 ML.A.201(e)’ provides examples of aircraft not considered to be operated by a commercial ATO or a commercial DTO.
Updated on 23/07/2021

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