EASA Flight Data Monitoring: The New FDM Rules for 2028

On 1 January 2028, the amended Acceptable Means of Compliance and Guidance Material to ORO.AOC.130 apply in full to every EASA-regulated aeroplane operator. The obligation to run a flight data monitoring programme is not new. What is new is the document against which that programme is measured — and it sets numbers where it previously set expectations.

This article sets out what the new EASA FDM requirements say, where the work actually sits, and how long it realistically takes.

What changed: ED Decision 2025/020/R

On 2 December 2025 EASA issued ED Decision 2025/020/R, Amendment 29 to the AMC & GM to Part-ORO. ORO.AOC.130 itself was not touched — an ED Decision amends Acceptable Means of Compliance and Guidance Material, not the Regulation, which only the Commission can change. What was rewritten is AMC1 ORO.AOC.130, and a wholly new AMC2 ORO.AOC.130 was introduced alongside amended Guidance Material.

That distinction matters less in practice than it sounds. AMC is formally non-binding, and an operator may always propose an alternative means of compliance. But AMC is the route almost every operator takes, and it is the material a competent authority opens when it assesses a programme. Rewriting it moves where the bar sits.

The existing text remains in force until 31 December 2027. From 1 January 2028, the amended text is the standard. EASA set that interval deliberately, noting that implementation requires changes to operators' procedures, updates to software, and in some cases a revision of the agreements concluded with flight crew representatives.

The new EASA FDM thresholds: from judgement to measurement

The character of the amendment is best described as a move from judgement to measurement. Where the previous AMC asked for a "sufficiently representative capture of flight information", the amended text specifies figures.

• Valid data coverage. A minimum of 60% of flights for operators with fewer than 20 aeroplanes in scope, or 80% for operators with 20 or more, assessed over a rolling twelve-month period.
• Processing time. At least 80% of collected flights processed within 22 calendar days of the flight, or before ten subsequent flights by the same aircraft.
• Detecting a collection failure. A failure of the means of collecting data from an individual aeroplane identified within 22 days or ten flights.
• Correcting a collection failure. Corrected within 120 days.
• Validating events. At least 80% of significant FDM events validated within 15 calendar days of first detection.
• Data retention. Raw or decoded flight data available for processing, for at least 80% of files, for at least two years.

Guidance Material adds three advisory internal objectives it describes as sufficiently ambitious: collection from 90% of flights, detection of a collection failure within ten days, and processing of 90% of collected flights within ten days. Those are not binding, but they are published, and an operator should expect to be asked how its own targets compare.

Three properties of these figures matter more than the figures themselves.

They are population statistics over a rolling twelve months, not monthly event counts, and they must be available continuously rather than assembled before an audit.

The processing clock starts at the completion of the flight, not at the receipt of the data file. That puts media exchange, wireless transmission reliability and decoder scheduling inside the measure.

Validation now has a narrow definition — determining whether an event corresponds to a genuine and abnormal event — which explicitly excludes analysis of causes and assessment of risk. A review process that bundles triage, investigation and risk assessment into one step is not measuring the thing the fifteen-day clock covers.

What EASA flight data monitoring must now cover

AMC2 ORO.AOC.130 is new in its entirety. A core set of FDM events and measurements must address the most significant risks the operator has identified, and must identify departures from standard operating procedures going beyond normal practice — expressly, more than those occurrences already subject to mandatory reporting.

For every aeroplane in scope first certificated on or after 1 January 2016, the programme must monitor the precursors of four key risk areas:

1. Excursion at take-off and landing
2. Aircraft upset
3. Collision with terrain
4. Airborne collision

The familiar guidance table of event groups — approach speeds, landing flap, bank angles, normal acceleration, ground proximity warning operation, flight manual limitations — has been withdrawn in full. It is the origin of most event libraries in service today. In its place sits Table 1 to GM2: 85 example precursors drawn from European Operators Flight Data Monitoring forum work, each mapped to a key risk area and, where such a relationship exists, to a type of occurrence under Regulation (EU) 2015/1018.

The table is illustrative rather than a compliance checklist, but it is the only worked example the Agency publishes. Several of those precursors are uncomfortable reading for an inherited library. Centre-of-gravity position ordinarily requires a source outside the aircraft. Deep landing and reduced time to terrain impact need runway geometry and terrain data alongside the flight data. The precursors an operator cannot compute from the parameters it decodes today, rather than the regulation itself, determine the scale of the work required.

FDM inside the management system

A quieter set of amendments moves the programme inside the management system. The safety manager is named as responsible for its effective use. The safety review board must monitor its effectiveness. Compliance monitoring must extend to it — meaning the internal audit programme now has to audit FDM.

None of this changes what the programme does. It changes who is accountable for it and how visibly it is governed.

Access to FDM algorithms: the obligation that is not yours to fix

One provision is different in kind from the rest. Point (l) of AMC1 ORO.AOC.130, headed "Access to information on flight parameters and FDM algorithms", requires the operator to have unhindered access to information on the flight parameters and on the algorithms used to produce FDM events and measurements.

For aircraft first certificated on or after 1 January 2029, that information must be available as documentation, on request, within 90 calendar days — including a description of each algorithm's logic in sufficient detail to verify consistency with flight manual limitations or standard operating procedures, and, for an event algorithm, its trigger conditions and trigger threshold values.

Read plainly, a proprietary event library whose logic and thresholds cannot be obtained in documentary form will not satisfy this. Every other obligation in the amendment lies within an operator's own gift. This one depends on decisions a software provider took years ago, and it has no remedy at the operator's end.

Guidance is unusually helpful on the consequence. On a change of FDM software or service provider, EASA advises keeping the previous system operative for several months, to ensure continuity and to validate the output of the new one. Parallel running is now a published recommendation rather than a nervous request from the safety department — and it belongs in both the transition plan and the budget.

Questions worth putting to an FDM provider in writing

• Can you supply, as documentation, the trigger conditions and threshold values behind every event in our library?
• Within what period, and at what cost, if any?
• Which of Table 1's 85 example precursors can your system compute from our current parameter set?
• What is required for the remainder — additional parameters, external data, or development?
• Can the system report valid-data coverage, flight-to-processed time and detection-to-validated time as rolling twelve-month population statistics, on demand?

The 2029 fleet: additional EASA FDM requirements

A distinct set of obligations attaches to any aeroplane in scope first issued a certificate of airworthiness on or after 1 January 2029, each on a 90-day clock from entry into service:

• The data collected for FDM must include every parameter required to be recorded by a flight data recorder under AMC1.2 CAT.IDE.A.190 — not a working subset.
• Those parameters must be verified against the performance specifications of EUROCAE ED-112A.
• The parameter and algorithm documentation of point (l) must be available on request.

Because that verification may rest on manufacturer or installer documentation, the economical moment to secure it is the aircraft purchase agreement, not the ninety days after delivery.

Where to start

Measurement first. Three figures produced from operational data — twelve-month valid-data coverage per aircraft, the distribution of flight-to-processed time, and the distribution of detection-to-validated time for events the operator would classify as significant — establish the actual gap. Experience suggests one will prove comfortably compliant and another considerably less so, and that which is which is rarely predicted in advance.

Then the documents that need other people's signatures, because the crew identity procedure determines the critical path.

Then the mapping of the event library against the four key risk areas and Table 1.

The tooling comes last, and its scope is known only once the first three are done.

Frequently asked questions

What is ED Decision 2025/020/R?

ED Decision 2025/020/R is the EASA Executive Director decision issued on 2 December 2025 that introduces Amendment 29 to the Acceptable Means of Compliance and Guidance Material to Part-ORO. It rewrites AMC1 ORO.AOC.130, introduces a new AMC2 ORO.AOC.130, and amends the associated Guidance Material on flight data monitoring.

When do the new EASA FDM requirements apply?

The amended AMC and GM apply from 1 January 2028. The existing text remains in force until 31 December 2027. A further set of obligations attaches to aeroplanes first issued a certificate of airworthiness on or after 1 January 2029.

Does ORO.AOC.130 itself change?

No. ED Decision 2025/020/R amends Acceptable Means of Compliance and Guidance Material, not the Regulation. ORO.AOC.130 remains the requirement to establish and maintain a flight data monitoring programme; what changed is the material describing how compliance is demonstrated.

What is AMC1 ORO.AOC.130?

AMC1 ORO.AOC.130 is the principal Acceptable Means of Compliance for flight data monitoring. In its amended form it sets out the programme's objectives, the quantitative thresholds for data collection and processing, the governance arrangements within the management system, and — at point (l) — the requirement for unhindered access to information on flight parameters and FDM algorithms.

What is AMC2 ORO.AOC.130?

AMC2 ORO.AOC.130 is new in the amendment. It defines the scope of monitoring: a core set of FDM events and measurements addressing the operator's most significant risks, and, for aeroplanes first certificated on or after 1 January 2016, the precursors of four key risk areas.

What are the four key risk areas in the new EASA FDM rules?

Excursion at take-off and landing, aircraft upset, collision with terrain, and airborne collision.

What are the new FDM data thresholds?

Valid-data coverage of 60% of flights (fewer than 20 aeroplanes) or 80% (20 or more), over a rolling twelve months; 80% of flights processed within 22 calendar days; collection failures identified within 22 days and corrected within 120 days; 80% of significant events validated within 15 calendar days; and data retained and available for processing for at least two years.

The full guide

The 2028 FDM Rules sets out the amendment clause by clause across nineteen pages: all seven thresholds with their references, the four key risk areas and Table 1's 85 precursors, what the amendment now requires of FDM software, the questions to put to a provider in writing, and a twenty-question self-assessment checklist.

Download the guide →

If it would help to see how FlightVue handles the 2028 requirements, we would be glad to arrange a thirty-minute walkthrough: request a demo.

Sources: EASA ED Decision 2025/020/R, 2 December 2025 (Amendment 29 to AMC & GM to Part-ORO); Commission Regulation (EU) No 965/2012, point ORO.AOC.130; Commission Delegated Regulation (EU) 2020/2034; Commission Implementing Regulation (EU) 2015/1018; Regulation (EU) No 376/2014; EUROCAE ED-112A.

This article was drafted with AI assistance from the EASA source documents and reviewed before publication. The header image is AI-generated.