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Mandatory vs Voluntary Occurrence Reporting

Mandatory and voluntary occurrence reporting under Regulation (EU) No 376/2014: Article 4 categories and the 2015/1018 lists.

Dionysis Kefalas6 min readFor Part-145, CAMO and Air Ops staff

Part 2 of 5 in EASA Occurrence Reporting Show parts
  1. 1EASA Occurrence Reporting under 376/2014
  2. 2Mandatory vs Voluntary Occurrence Reporting
  3. 3How to File an Occurrence Report in 72 Hours
  4. 4Just Culture and Occurrence Reporter Protection
  5. 5Occurrence Analysis and Follow-up in the SMS

Quotes checked on against EASA Easy Access Rules for Occurrence Reporting (Regulation (EU) No 376/2014) — 27 Sep 2023 revision.

On this page

Mandatory and voluntary

A crack found on a scheduled check at ExampleMRO, a confusing handover at ExampleAir, a vehicle that stopped short of the wing. They can all land on an occurrence form. Regulation (EU) No 376/2014 does not treat them as one kind of report.

What is reported through the mandatory system

Article 4 (full rule text)Mandatory reporting

1.Occurrences which may represent a significant risk to aviation safety and which fall into the following categories shall be reported by the persons listed in paragraph 6 through the mandatory occurrence reporting systems pursuant to this Article:

(a)occurrences related to the operation of the aircraft, such as:

(i)collision-related occurrences;

(ii)take-off and landing-related occurrences;

(iii)fuel-related occurrences;

(iv)in-flight occurrences;

(v)communication-related occurrences;

(vi)occurrences related to injury, emergencies and other critical situations;

(vii)crew incapacitation and other crew-related occurrences;

(viii)meteorological conditions or security-related occurrences;

(b)occurrences related to technical conditions, maintenance and repair of aircraft, such as:

(i)structural defects;

(ii)system malfunctions;

(iii)maintenance and repair problems;

(iv)propulsion problems (including engines, propellers and rotor systems) and auxiliary power unit problems;

(c)occurrences related to air navigation services and facilities, such as:

(i)collisions, near collisions or potential for collisions;

(ii)specific occurrences of air traffic management and air navigation services (ATM/ANS);

(iii)ATM/ANS operational occurrences;

(d)occurrences related to aerodromes and ground services, such as:

(i)occurrences related to aerodrome activities and facilities;

(ii)occurrences related to handling of passengers, baggage, mail and cargo;

(iii)occurrences related to aircraft ground handling and related services.

Quoted word for word from Regulation (EU) No 376/2014, Easy Access Rules for Occurrence Reporting, 27 Sep 2023 revision.

The categories are "such as" lists, not a closed catalogue. The paragraph does not cover every defect or deviation.

The persons listed in paragraph 6 are quoted in EASA Occurrence Reporting: A Complete Guide for Aviation Professionals. This page does not repeat the list.

The classification list

Article 4 (full rule text)Mandatory reporting

5.The Commission shall, by means of implementing acts, adopt a list classifying occurrences to be referred to when reporting occurrences pursuant to paragraph 1. Those implementing acts shall be adopted in accordance with the examination procedure referred to in Article 19(2).

The Commission shall include in those implementing acts a separate list classifying occurrences applicable to aircraft other than complex motor-powered aircraft. The list shall be a simplified version of the list referred to in the first subparagraph and shall, where appropriate, be adapted to the specificities of that branch of aviation.

Quoted word for word from Regulation (EU) No 376/2014, Easy Access Rules for Occurrence Reporting, 27 Sep 2023 revision.

Article 1 (full rule text)Detailed classification

The detailed classification of the occurrences to be referred to when reporting, through mandatory reporting systems, occurrences pursuant to Article 4(1) of Regulation (EU) No 376/2014 is set out in Annexes I to V to this Regulation.

Quoted word for word from Commission Implementing Regulation (EU) 2015/1018, Easy Access Rules for Occurrence Reporting, 27 Sep 2023 revision.

Article 4(5) does not name which annex is the simplified list. The implementing regulation's Article 1 is the sentence that points at Annexes I to V. One maintenance point is quoted below because the example uses it.

Annex II — Occurrences related to technical conditions, maintenance and repair of the aircraft · Commission Implementing Regulation (EU) 2015/1018 · Easy Access Rules for Occurrence Reporting, 2023-09-27 revision

  1. MAINTENANCE AND CONTINUING AIRWORTHINESS MANAGEMENT (1) Serious structural damage (for example: cracks, permanent deformation, delamination, debonding, burning, excessive wear, or corrosion) found during maintenance of the aircraft or component.

That point sits under maintenance and continuing airworthiness management. It does not replace the opening test in Article 4(1).

What the voluntary system collects

Article 5 (full rule text)Voluntary reporting

1.Each organisation established in a Member State shall establish a voluntary reporting system to facilitate the collection of:

(a)details of occurrences that may not be captured by the mandatory reporting system;

(b)other safety-related information which is perceived by the reporter as an actual or potential hazard to aviation safety.

[…]

4.The voluntary reporting systems shall be used to facilitate the collection of details of occurrences and safety-related information:

(a)not subject to mandatory reporting pursuant to Article 4(1);

(b)reported by persons who are not listed in Article 4(6).

5.Each organisation established in a Member State and certified or approved by the Agency shall report to the Agency, in a timely manner, details of occurrences and safety-related information which have been collected pursuant to paragraph 1 and which may involve an actual or potential aviation safety risk.

6.Each organisation established in a Member State that is not certified or approved by the Agency shall, in a timely manner, report to the competent authority of that Member State, as designated pursuant to Article 6(3), the details of occurrences and other safety-related information which have been collected pursuant to paragraph 1 of this Article and which may involve an actual or potential aviation safety risk. Member States may require any organisation established in their territory to report the details of all occurrences collected pursuant to paragraph 1 of this Article.

[…]

8.Information received from voluntary and mandatory reporting may be integrated into a single system.

Quoted word for word from Regulation (EU) No 376/2014, Easy Access Rules for Occurrence Reporting, 27 Sep 2023 revision.

Point (a) and point (b) of paragraph 4 are separate. They are not one combined test.

Paragraph 5 is the organisation the Agency certifies or approves. Paragraph 6 is the organisation that is not. The wider permission, to require every occurrence collected under paragraph 1, is in paragraph 6. It is not in paragraph 5.

ExampleAir uses one intake form and sorts the report afterwards. Paragraph 8 allows a single system. It does not ask the reporter to choose the legal channel on the form.

A practical test

  1. Does it meet Article 4(1), the category and the risk test together? Then it is the mandatory stream, and the classification is in Annexes I to V.
  2. If not, does Article 5(1) catch it? Then it is the voluntary stream.
  3. If it is neither, these two articles are not the home for it. It may still be a quality or commercial matter.

Worked with fictional aircraft and organisations:

  • ExampleMRO finds a crack during maintenance of MSN-EXAMPLE-204. Read it against the Annex II point and against the opening test in Article 4(1). The annex example does not settle that test by itself.
  • ExampleAir identifies confusing handover wording before it causes an event. That is the voluntary side unless the same facts also meet Article 4(1).
  • ExampleAir finds a missing release document. Nothing quoted here calls that a records problem, or puts it outside occurrence reporting.
  • Someone at ExampleAir sees a vehicle stop short of an aircraft. Do not call it voluntary because of the job title. The category test and the question of who is on the Article 4(6) list are different sentences in the quotes.

Where Article 4(1) is genuinely unclear, use the voluntary system rather than dropping the event.

Where this fits the work

The classification list is what makes the later search possible. Avioverse's occurrence lookup can help you inspect ECCAIRS and ADREP fields and values. The lookup does not decide whether Article 4(1) applies, and it does not replace Annexes I to V. The reporter and the organisation still check the event against those texts.

Once the stream is clear, the filing guide quotes the time limits and the handling rules: How to File an Occurrence Report: The 72-Hour Deadline and Data Quality.

Educational content, not regulatory compliance advice. Verify against the current regulation text before relying on it.

In this series

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Written by Dionysis Kefalas. Retired Hellenic Air Force Captain and founder of Avioverse. About the author

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