M.A.903 Airworthiness review process

OTHER REGULATORY REQUIREMENTS AFFECTING AIRCRAFT CONFIGURATION For efficiency and to promote synergies, the organisation or competent authority that conducts the airworthiness review may choose to verify compliance with requirements that are outside the scope of the airworthiness review. This may include, in particular, requirements concerning equipment required to be carried on board, as well as components required to be installed on the aircraft, if these are related to operational requirements. However, it should be noted that such additional verifications or their results should not compromise the completeness, scope or result of the airworthiness review. Specifically, the time allocated to verifying items directly relevant to the airworthiness review should not be diverted to the assessment of requirements that are outside its scope. Examples of such additional requirements include those established in: — Annex V (Part-SPA) and Subpart D of Annex IV (Part-CAT), Annex VI (Part-NCC), Annex VII (Part- NCO), and Annex VIII (Part-SPO) to Regulation (EU) No 965/2012; — Annex I (Part-26) to Regulation (EU) 2015/640; — Implementing Regulation (EU) 2023/1770 laying down provisions on aircraft equipment required for the use of the Single European Sky airspace and operating rules related to the use of the Single European Sky airspace; — Regulation (EU) 1332/2011 laying down common airspace usage requirements and operating procedures for airborne collision avoidance. Any non-compliances identified in relation to these additional requirements may be recorded as observations in the airworthiness review report. Although confirming the presence of components required for specific operational purposes is not within the scope of the airworthiness review, any such components, if installed, should still be checked such as any other during the airworthiness review. For example, if the component is part of a modification, it may be selected for sampling during the airworthiness review. In such a case, it should be verified that it complies with point M.A.304, that a corresponding maintenance release was issued following its installation, and that the component is physically installed on the aircraft.

DOCUMENTED REVIEW AND PHYSICAL SURVEY

(a)The documented review of the aircraft’s records and the physical survey of the aircraft could be based on samples and should cover the following:

(1)Aircraft continuing airworthiness record system — the total in-service life accumulated in the applicable parameter for aircraft, engine(s), propeller(s), life-limited parts and time-controlled components has been properly recorded (e.g. flight hours, flight cycles, APU hours, engine hours); — aircraft, engine, propeller, life-limited part and time-controlled component maintenance entries are up to date and correct; and — as applicable, technical log system entries.

(2)Aircraft flight manual (AFM) — the aircraft flight manual and its supplements are applicable to the current aircraft configuration, including any revisions issued by the design organisation when mandated by ADs, and correspond to the version carried on board.

(3)AMP — the AMP includes the mandatory continuing airworthiness requirements; — reference to the approval and revision status; and — the applicable maintenance as required by the maintenance programme has been carried out or carried forward in a controlled manner.

(4)Aircraft defects and rectification — defects have been recorded and rectified in accordance with applicable maintenance data, or deferred in accordance with point M.A.403; — if available, the dent and buckle chart, or similar, accurately reflects the current condition of the aircraft; — deferred defects are within any limits specified in the maintenance data or the MEL/CDL; and — no evident defect can be detected that has not been addressed in accordance with to point M.A.403.

(5)Airworthiness directives (ADs) — applicable ADs are properly recorded in accordance with AMC M.A.305(c)1; — applicable ADs and measures mandated by the competent authority in immediate reaction to a safety problem are not overdue; and — ADs have been properly complied with, if applicable, as evidenced by the corresponding maintenance release and, if feasible and appropriate, by physical confirmation on the aircraft.

(6)Modifications and repairs — modifications and repairs that have been embodied are properly recorded in accordance with AMC M.A.305(c)2; — modifications and repairs have been carried out in accordance with the applicable data, as defined in point M.A.304; — the physical configuration of the aircraft is consistent with the recorded status of modifications and repairs; and — any potential impact on airworthiness resulting from conflicting modifications and/or repairs has been identified and appropriately addressed.

(7)Life-limited parts and time-controlled components — the approved life limit of life-limited parts and the operating time of time- controlled components have not been exceeded; — the life-limited parts and time-controlled components installed on the aircraft accurately match the details recorded in the continuing airworthiness record system; and — the in-service history of life-limited parts is properly recorded.

(8)Mass and balance — the current mass and balance statement reflects the current aircraft configuration.

(9)Approved design — the aircraft complies with the configuration elements specified in GM1 M.A.301; — the aircraft, engine and propeller comply with the relevant elements of the type certificate data sheet (TCDS) or airworthiness data sheet, as applicable, such as certification maintenance requirements and specific maintenance requirements; — markings and placards are in accordance with the approved design and are written in one or more of the official languages of the European Union, as accepted by the competent authority of the Member State of registry; — the identification plates of the aircraft, engine(s), propeller(s), as applicable, are installed and display accurate information; and — if applicable, the layout of passenger accommodation (LOPA) complies with the approved configuration.

(10)Aircraft certificates — if issued, the certificate of registration, airworthiness certificate and noise certificate are checked for their validity. Their contents are accurate and consistent with the nationality and registration marks displayed on the aircraft and with the identification plate(s).

(11)Maintenance — maintenance has been released in accordance with Regulation (EU) No 1321/2014; — if applicable, during the period when the aircraft was not within the scope of Regulation (EU) No 1321/2014, the maintenance has been released in accordance with appropriate airworthiness requirements of the State which was responsible for the oversight of the aircraft, as specified in AMC1 M.A.903(b)(12)(ii); and — components that have been replaced are eligible for installation according to a design approved under Regulation (EU) No 748/2012 or an applicable EU bilateral agreement.

(b)The content of Appendix III to GM1 M.B.303(b) may serve as a reference when developing a checklist for conducting the airworthiness review.

(c)If the previous airworthiness review was incomplete in accordance with point M.A.903(f), the reasons for its interruption should be reviewed; for example, whether unresolved findings have contributed to the interruption.

(d)The airworthiness review should not be conducted under conditions that could adversely affect human performance and potentially have a negative impact on the outcome of the assessment. Such conditions may negatively impact both the accuracy of the airworthiness review and the effectiveness of the staff involved since they touch on crucial human factors such as perception, decision-making and physical performance. The following are examples of such conditions:

(1)Excessive noise, which can compromise communication and the focus.

(2)Performing the physical survey of the aircraft outside a hangar during adverse weather or at night.

(3)Inadequate or excessive lighting, which may affect the reading of documents and the identification of potential damage during the physical survey.

(4)Excessive operational pressure put on airworthiness review staff to expedite the airworthiness review process, which can lead to rushed investigations and the potential to overlook critical issues.

(5)Physical or mental fatigue among the staff involved in the airworthiness review, stemming from long working hours, travel to the location where the airworthiness review is to be conducted (e.g. jetlag, duration), or excessive workload. If such conditions exist, the airworthiness review may only be conducted if they are adequately mitigated.

AIRWORTHINESS REVIEW SAMPLING

(a)In order to perform an airworthiness review based on sample checks, the approved organisation should establish a procedure, approved by the competent authority, considering the following:

(1)A sampling method should be defined, preferably using statistical principles, to ensure both comprehensiveness and reliability. The method should follow an internationally recognised sampling standard or should be supported by historical data from previous airworthiness reviews. The use of simple linear sampling rules, such as the ‘10 % of the population’, is not recommended as they tend to be unreliable, producing overly large samples for large populations and underrepresenting small ones.

(2)The minimum sample size should be specified taking into account the number of items per type of information, as illustrated by the example in GM1 M.A.903(b);(c). This allows a minimum sample size to be determined during the airworthiness review, based on the number of items under review (population), so that by checking that sample an overall representation of the items within that information set is obtained. The ‘population’ depends on the type of information under review, as specified in AMC1 M.A.903(b);(c). For the purposes of determining the population, only those items required to be retained in accordance with the applicable requirements (e.g. point M.A.305) should be considered, using, if necessary for large populations, a reasonable approximation. This may include, for example, the total number of applicable ADs, the total number of embodied modifications, or the total number of technical log entries covering the previous three years.

(3)A risk-based approach should be applied to determine whether the minimum sample size for a particular airworthiness review should be increased. For example, the parameters of the statistical method, such as the confidence level for the expected percentage of compliant items, may be adjusted to reflect the level of risk associated with a particular aircraft. This results in a larger sample size for cases in which there are higher uncertainties or concerns regarding the aircraft’s airworthiness. Therefore, the sample size should be increased based on factors such as but not limited to: — aircraft that have been recently imported (in the process of being imported or imported during the previous airworthiness review); — the ICAO airworthiness implementation score of the State from which the aircraft is being or was imported; — aircraft for which the airworthiness certificate has been recently revoked or surrendered; — aircraft that its continuing airworthiness has been managed by multiple persons or organisations since the last airworthiness review; — judgement of the airworthiness review staff, for example, considering the criticality of certain items or known issues affecting specific areas.

(4)As a general principle, once the sample size has been determined, the items included in the sample should be randomly selected from the entire relevant population. However, in certain situations, deviation from random selection may be justified. For example: — in the case of conducting airworthiness reviews to a fleet of similar aircraft, the sample should vary between aircraft to avoid reviewing the same items repeatedly for the different aircraft; — judgemental sampling may take precedence based on the airworthiness review staff’s professional judgement, particularly when specific items are known to be problematic or carry higher criticality.

(5)In relation to the aircraft continuing airworthiness statuses required by point M.A.305, such as status of ADs, modifications, repairs and life-limited parts, it is essential that this information be complete and up to date in order to determine the appropriate sample size.

(6)The investigation of each item should confirm the status of the item, if applicable and practicable, by covering the complete process. For example, for a modification, this includes verifying that it is approved, reviewing the maintenance records of its installation, confirming the availability and compliance with any applicable ICAs, and checking its physical embodiment on the aircraft.

(7)Although the focus of the airworthiness review is on the period since the last ARC was issued, the selected sample should also include items dated prior to the previous airworthiness review.

(8)Criteria and provisions should be established to allow airworthiness review staff to consider interrupting the airworthiness review, in accordance with point M.A.903(f), for example, for cases in which a significant number of non-compliances is identified relative to the selected sample size. A considerable number of findings may indicate deficiencies in the continuing airworthiness management process, and the root cause(s) could potentially affect other areas of continuing airworthiness management or even other aircraft. It should be emphasised that the airworthiness review is intended to confirm that the aircraft is in an airworthy condition, and not to compensate for deficiencies in the continuing airworthiness management of the aircraft.

SAMPLE SIZE As an example, the following table describes the required sample size for each possible number of items per type of information (population) to have 95 % confidence that at least 80 % of the items of the population are correct if the technique described below is followed. Number of items per type of information Sample size (population) 1 to 5 All items 6 to 10 6 11 to 16 8 17 to 25 9 26 to 35 10 36 to 55 11 56 to 100 12 101 to 1000 14

(i)This sampling technique assumes zero tolerance for non-compliances within the sample. If a non-compliant item is identified, all previously checked items (including the non-compliant one) must be excluded from the population, and the sampling process must be restarted to retain the intended level of confidence of the percentage of compliant items. For example: — initial population size: 38 — required sample size (check table above): 11 — first six items checked are compliant; the seventh item is non-compliant — remove all seven checked items from the population — new population size: (38–7) = 31 — recalculate a new sample size (check table above): 10 — restart the sampling process

(ii)Based on the expected frequency of specific airworthiness review scenarios (e.g. a significant number of aircraft imports), and if justified, a dedicated sampling table tailored to that scenario may be developed. Otherwise, the minimum sample size applicable to ‘standard’ airworthiness reviews may be used as a baseline. In such cases, the sample size may be increased, as necessary, during the performance of the airworthiness review, taking into account the risk indicators identified.

MAINTENANCE PERFORMED WHILE THE AIRCRAFT WAS OUTSIDE THE SCOPE OF REGULATION (EU) No 1321/2014 When an airworthiness review is conducted on an aircraft that in the past was subject to different a regulatory framework, such as a used aircraft imported from a third country or one that has carried out activities or services as defined in Article 2(3)(a) of the Basic Regulation (e.g. police operations, search and rescue, firefighting), it should be expected that, during such period, maintenance was performed in accordance with the rules accepted by the aviation authority responsible for the oversight of the aircraft at the time. During the airworthiness review, the maintenance certificates required to demonstrate compliance with point M.A.305, which were issued while the aircraft was outside the scope of Regulation (EU) No 1321/2014 should be verified to ensure that they contain the following information:

(a)details of the maintenance performed including detailed reference to the data used;

(b)the date on which such maintenance was completed;

(c)if applicable, the identity of the maintenance organisation; and

(d)the identity of the person signing the maintenance release including the licence or authorisation number of that person. It should be confirmed that the maintenance organisation’s approval is recognised by the appropriate authority that was responsible for the oversight of the specific aircraft or component. Additionally, if maintenance has been performed by individuals acting on their behalf, it should be verified that this practice was permitted by the aviation authority in charge of the oversight of the aircraft at that time. During the physical survey, it should be confirmed that there are no uncertainties regarding the maintenance performed or indications of absence of the required maintenance. If there are doubts about the adequacy of the maintenance performed, including concerns regarding its quality or integrity, which may include: — indications that maintenance may not have been properly performed (e.g. poor maintenance standards or maintenance released but not performed); — evidence that maintenance was performed by non-approved entities, or without adequate oversight; — significant gaps or missing information in maintenance records, maintenance may need to be performed again or thoroughly inspected by an approved organisation or a person authorised under Regulation (EU) No 1321/2014 to ensure that the aircraft meets the necessary airworthiness standards.

PHYSICAL SURVEY

1.The physical survey may require actions categorised as maintenance (e.g. operational tests, tests of emergency equipment, visual inspections requiring panel opening, etc.). In this case, after the airworthiness review, a maintenance release should be issued.

2.When the airworthiness review staff are not appropriately qualified certifying staff in order to release such maintenance, point M.A.903(d) requires them to be assisted by such qualified personnel. However, the function of such certifying staff is limited to performing and releasing the maintenance actions related to the physical survey as requested by the airworthiness review staff; it is not their function to perform the physical survey of the aircraft.

3.This means that the airworthiness review staff that is going to sign the airworthiness review certificate ARC or the recommendation should be the one responsible for the accomplishment of both the documented review and the physical survey of the aircraft.

4.The physical survey may include verifications to be carried out during flight.

5.The physical survey should not be performed remotely, meaning that the airworthiness review staff should be physically present.

AIRWORTHINESS REVIEW PLANNING

(a)One of the primary objectives of the airworthiness review is to ensure that the information within the aircraft continuing airworthiness records is consistent with the actual configuration and condition of the aircraft. Airworthiness review staff are responsible for determining the most effective method for this verification, ensuring that the time elapsed between the verification of an item in the documented review and its corresponding physical survey (or vice versa) should not exceed 30 consecutive days. Furthermore, the time span from the start until the completion of the airworthiness review should be within a reasonable time frame. This is to avoid a misalignment between the verifications conducted during the airworthiness review and the actual status of the aircraft at the time the ARC or recommendation is issued. Airworthiness review staff are responsible for determining what constitutes a reasonable time frame, considering factors such as aircraft utilisation, maintenance performed, time required to address the findings, and ADs issued during the airworthiness review period. It is up to the airworthiness review staff to determine whether there is a need to repeat certain verifications, or as a last resort, to interrupt the airworthiness review and initiate a new one.

(b)To ensure the effectiveness of the airworthiness review, it is recommended that the physical survey be scheduled, if practicable, to be carried out during maintenance, in order to allow access to areas that are otherwise difficult to access and to avoid time pressure due to operational constraints. It should be noted that this does not imply that the entire physical survey is to be carried out at a single point in time; for example, while the aircraft is disassembled during heavy maintenance. Certain items, such as placards, can only be verified once maintenance is nearing completion. Accordingly, the physical survey may be performed in phases, depending on the items to be verified. In addition, as specified in GM1 M.A.901(h) and M.A.902(b), it should be ensured that the ARC or recommendation is not issued if there is evidence or indication that the aircraft is not airworthy. Therefore, it is expected that the ARC or recommendation is issued only upon completion, or near completion, of the maintenance activities.

INCOMPLETE AIRWORTHINESS REVIEW An airworthiness review is considered satisfactorily completed if it has been conducted in accordance with the applicable requirements and procedures, resulting in the issuance of an ARC or a recommendation, as applicable. This includes the closure all findings raised during the airworthiness review, and confirmation that there is no evidence or reason to believe that the aircraft is not airworthy. An incomplete airworthiness review refers to a situation in which the review process is interrupted and cannot be finalised, resulting in neither an ARC nor a recommendation being issued. The following are examples of situations that may lead to an incomplete airworthiness review: — Findings not addressed or not corrected within a reasonable time frame — Failure to provide the necessary support to airworthiness review staff as required by point M.A.901(e), such as denying access to the aircraft or its records — Lack of cooperation with the airworthiness review staff — Identification of a significant number of discrepancies within the selected sample size. Repeated detection of non-compliances may indicate systemic deficiencies in the continuing airworthiness management An airworthiness review report in accordance with AMC1 M.A.903(h) should be produced even in the case of an incomplete airworthiness review. However, since the airworthiness review is incomplete, it is not necessary to fill in all the information that is typically required. Only the information that is available and known should be included in the report. The reasons for the interruption of the airworthiness review should be indicated as an observation in the airworthiness review report. The competent authority of the Member State of registry should be informed of the reasons leading to the interruption of the airworthiness review, and should take appropriate actions, which may include: — if different, notifying the competent authority responsible for the organisation that manages the continuing airworthiness of the aircraft; — conducting an airworthiness review under point M.B.901(b); — including the aircraft in the ACAM programme; — closely monitoring the situation of the aircraft and, if necessary, suspending or revoking its ARC in accordance with point M.B.304(a).

MANAGEMENT OF NON-COMPLIANCES

(a)Non-compliances detected during the airworthiness review should be reported as findings to the person or organisation that is responsible for the continuing airworthiness of the aircraft. It should be noted that airworthiness review staff are subject to occurrence reporting requirements while performing the airworthiness review.

(b)Airworthiness review staff should verify that the reported non-compliance(s) have been properly addressed. This includes reviewing the actions taken to correct the non-compliance(s), such as rectification or deferral of defects, together with the supporting evidence provided, and, if necessary, performing a physical verification on the aircraft to confirm the implementation of those actions. Deferring a defect in accordance with point M.A.403 is considered an acceptable means of addressing a non-compliance.

(c)Although the corrections may be sufficient to close the airworthiness review findings and to issue the ARC or the recommendation, the root cause(s), contributing factor(s) and corrective action(s) should be determined by the organisation that is responsible for the continuing airworthiness of the aircraft, in accordance with its procedures. This may reveal underlying weaknesses in the continuing airworthiness management process and helps prevent the recurrence of non-compliances. Similarly, if a person is responsible for the continuing airworthiness, it is recommended that the same principle be followed.

AIRWORTHINESS REVIEW REPORT

(a)The airworthiness review report should include at least the following:

(1)General information — the CAMO, CAO or competent authority that conducts the airworthiness review, including name and, except in the case of the competent authority, the approval number; — the person or organisation that is responsible for the continuing airworthiness of the aircraft in accordance with point M.A.201, including the name and, in the case of an organisation, the approval number; — aircraft owner or operator, including the name and address; — the date and place the documented review and the physical survey were conducted; and — a list of the organisations or persons that were responsible for the continuing airworthiness of the aircraft since the issuance of the former ARC.

(2)Aircraft information — aircraft registration, or the assigned registration, as applicable; — aircraft/engines/propellers, manufacturer, type and serial number; — if applicable, aircraft flight manual reference and current revision; — if applicable, noise certificate reference; — reference to the current mass and balance statement reflecting the current configuration of the aircraft; — AMP reference and current revision.

(3)Aircraft status — aircraft total time and cycles.

(4)Documented review — evidence and details of the review of the continuing airworthiness records in accordance with point M.A.305, including sampled items; and — checklist/report covering the items defined in point M.A.903(b).

(5)Physical survey — a precise list of the areas of the aircraft that were surveyed and their status (a description referring to wings, fuselage, interior, etc., is not considered detailed enough); — evidence and details of sampled items, if appropriate; and — checklist/report covering the items defined in point M.A.903(c).

(6)Findings: — a list of all the findings linked to the airworthiness of the aircraft raised during the airworthiness review; and — feedback on the actions taken per raised finding from the person or organisation responsible for the aircraft continuing airworthiness in accordance with point M.A.201.

(7)Observations — if any, a list of all the observations raised during the airworthiness review. Observations should record relevant information that does not constitute a finding, such as non-compliances with requirements outside the scope of the airworthiness review (e.g. operational requirements) as explained in GM1 M.A.903.

(8)Personnel — details of airworthiness review staff including name and, if applicable, the authorisation number; and — if applicable, the name (or details) of the person(s) and certifying staff that assist during the airworthiness review.

(9)Issuance of the ARC (EASA Form 15b) or recommendation: — a statement indicating whether the conditions in point M.A.901(b)(1) are met.

(b)A copy of the airworthiness review report should be sent to the person or organisation that is responsible for the aircraft continuing airworthiness in accordance with point M.A.201. If, during the assessment of the recommendation by the competent authority, any mistakes or errors are detected, the airworthiness review report should be amended by the airworthiness review staff that performed the airworthiness review, and a new copy should be sent to the person or organisation that is responsible for managing the continuing airworthiness of the aircraft.