From EU-OPS to Part-CAT: What Changed in EASA Operations Rules

For years European airline crews flew under EU-OPS, the regulation that turned the JAA's JAR-OPS 1 into European Union law. Since 2014 the same ground has been covered by the Air Operations Regulation (EU) No 965/2012, usually called EU Air OPS, in which the conduct of commercial flights sits in Part-CAT and the operator's organisation in Part-ORO. Much of the content came across with little change, some of it moved out of the rule into acceptable means of compliance, and in 2021 two packages rewrote fuel planning and all-weather operations with effect from October 2022.

The history matters because training material ages more slowly than the law. Textbooks, operations manuals and question banks still quote EU-OPS paragraph numbers, the fuel policy and categories such as CAT IIIA. This article traces the line from JAR-OPS 1 to the current rules, maps the old references to the new ones, and lists the later changes that most often catch candidates out, including several outside Air OPS: runway condition reporting, the North Atlantic High Level Airspace and the 2025 amendment of the rules of the air. The legal structure itself is described in EASA regulatory framework.

JAR-OPS 1 and EU-OPS

The Joint Aviation Authorities (JAA) wrote common requirements for their member authorities, and JAR-OPS 1 was the code for commercial air transport by aeroplane. Like every JAR, it bound no one until a State wrote it into national law, and States could do so late or with differences. The European Union closed that gap by making the code binding as EU-OPS, an annex to an EU regulation, usually cited in the version of Commission Regulation (EC) No 859/2008. The JAA itself closed in 2009.

EU-OPS applied only to civil aeroplanes engaged in commercial air transport. Flights such as parachute dropping and fire-fighting, including positioning for them, were outside it, and it said nothing about non-commercial flying. Its paragraphs were numbered EU-OPS 1.001 onwards and grouped in lettered subparts, among them Subpart E for all-weather operations, Subpart J for mass and balance and Subpart Q for flight and duty time limitations. Detailed figures often sat in numbered appendices, such as Appendix 1 to EU-OPS 1.525(b), which held the take-off climb gradients of multi-engine Class B aeroplanes.

EU Air OPS and Part-CAT (2014)

Commission Regulation (EU) No 965/2012 of 5 October 2012 replaced EU-OPS in 2014. It splits the subject into annexes, each called a Part: definitions in Annex I, Part-ARO for the authorities, Part-ORO (Annex III) for operator organisations, Part-CAT (Annex IV) for commercial air transport and Part-SPA (Annex V) for specific approvals, plus Part-NCC, Part-NCO and Part-SPO for the non-commercial and specialised operations that EU-OPS never covered. Rule references name the Part, the subpart and the section: CAT.OP.MPA.181 is an operating procedure, CAT.POL.A.230 an aeroplane performance limitation, ORO.FTL.210 a flight time limitation.

Three changes of structure run through the conversion.

• Organisation and operation were separated. What an operator must be, with its management system, nominated persons, training and manuals, went to Part-ORO; how each flight is flown went to Part-CAT. The EU-OPS quality system became compliance monitoring inside a management system that also covers safety management (ORO.GEN.200), and the accident prevention and flight safety programme of EU-OPS 1.037 was absorbed into it. ORO.AOC.130 requires flight data monitoring for aeroplanes with a maximum certified take-off mass above 27,000 kg.
• Detail moved into soft law. Many figures written into EU-OPS now sit in acceptable means of compliance (AMC). The alcohol rule is an example: no alcohol in the 8 hours before reporting, and a blood alcohol level not above 0.2 per thousand, now in the AMC to CAT.GEN.MPA.100 (formerly EU-OPS 1.115). The EU-OPS head count for nominated post holders disappeared; AMC2 ORO.AOC.135 judges whether one person may hold several posts on the nature and scale of the operation.
• Approvals became a Part of their own. Low visibility operations, RVSM, RNP AR approaches and ETOPS are specific approvals under Part-SPA, available to any operator whatever Part it flies under (see specific approvals).

Some figures changed on the way. Flight crew duty records are now kept for 24 months (ORO.FTL.245) instead of 15. The operations manual no longer has to be in English unless approved otherwise; ORO.MLR.100 asks only that personnel understand the parts relevant to their duties. The list of critical phases of flight now includes the missed approach, which EU-OPS 1.192 left out.

Mapping EU-OPS to Part-CAT and Part-ORO

Most exam questions that cite EU-OPS have a current counterpart. The commonest are:

Content can change while the subject stays put. The secured flight deck door of ORO.SEC.100 applies above 54,500 kg, above 45,500 kg with more than 19 passenger seats, or with more than 60 seats, where EU-OPS 1.1255 used 45,500 kg or 60 seats. Since 1 January 2019 every CVR on an EASA commercial aeroplane must record at least the last 2 hours, and aeroplanes above 27,000 kg first issued with a certificate of airworthiness on or after 1 January 2021 need 25 hours. Performance rules, by contrast, came across almost unchanged: the 60 per cent dry landing rule for turbojets and the 15 per cent wet increment of CAT.POL.A.230 and 235 are the EU-OPS figures.

The 2022 fuel/energy rules

Commission Implementing Regulation (EU) 2021/1296, applicable from 30 October 2022, replaced the fuel policy, which EU-OPS 1.255 had set out and Part-CAT had carried in CAT.OP.MPA.150 (now blank), with a fuel/energy scheme. CAT.OP.MPA.180 requires the scheme, which has three parts: fuel planning and in-flight re-planning (CAT.OP.MPA.181), aerodrome selection (CAT.OP.MPA.182) and in-flight fuel management (CAT.OP.MPA.185). The AMC, in ED Decision 2022/005/R, offer a basic fuel scheme, a basic fuel scheme with variations and an individual fuel scheme derived from the operator's own data with its authority's approval.

The component names survived, and so did the final reserve quantities: 30 minutes at holding speed at 1,500 ft above aerodrome elevation in standard conditions for turbine-engined aeroplanes, and 45 minutes for piston-engined aeroplanes. Several details moved:

• The 3% ERA, the en-route alternate that allows contingency fuel to fall from 5 to 3 per cent of trip fuel, is now called a fuel ERA.
• An isolated destination needs the competent authority's prior approval (CAT.OP.MPA.106). The EU-OPS test, fuel to the nearest adequate alternate plus final reserve exceeding 2 hours at normal cruise consumption for a turbine aeroplane, survives only in older questions.
• Planning minima for alternates add increments to the minima of the approach available. Under the basic scheme a Type B approach needs DA/H + 200 ft and RVR/VIS + 800 m, and a single Type A approach MDA/H + 400 ft and RVR/VIS + 1,500 m. EU-OPS used the CAT I RVR for an alternate with a CAT II or III approach, and MDH + 200 ft with + 1,000 m for a non-precision approach.

Non-commercial flying changed on the same date: NCO.OP.125 no longer states figures, which now sit in its AMC (see fuel planning and reserves and EU fuel schemes).

The 2022 all-weather operations rules

Commission Implementing Regulation (EU) 2021/2237, also applicable from 30 October 2022, rewrote the all-weather rules that Air OPS had largely carried over from EU-OPS Subpart E, and aligned their terms with ICAO. The changes most often examined are:

• Approach operations are classed as Type A, with a minimum descent height or DH at or above 250 ft, or Type B, with a DH below 250 ft, divided into CAT I, CAT II and CAT III.
• CAT III is a single category: a DH below 100 ft or none, and an RVR below 300 m or no limit. The EU-OPS subdivision into IIIA, IIIB and IIIC has gone, and the lowest RVR for a DH between 50 ft and 100 ft fell from 200 m to 175 m.
• Where the DH and the RVR fall in different categories, the more demanding category applies; under EU-OPS the RVR decided.
• A low visibility take-off is one in an RVR below 550 m, not 400 m, although only take-offs below 400 m need an approval under SPA.LVO.
• Lower than standard CAT I and other than standard CAT II became SA CAT I and SA CAT II, joined by other operations with operational credits.
• The touchdown zone RVR is controlling, and midpoint and stop-end values are advisory.

The detail is in EU all-weather operations rules.

Runway condition reporting: the Global Reporting Format

Runway surface reporting changed under ICAO's Global Reporting Format (GRF), applicable worldwide from 4 November 2021; EU rules applied it a little earlier, from 12 August 2021. The aerodrome now assesses each third of the runway and gives it a runway condition code (RWYCC) from 6, dry, to 0, braking action less than poor, using the Runway Condition Assessment Matrix. The result reaches crews in a runway condition report, through the ATIS and the SNOWTAM, which now describes contaminants in plain language and is valid for at most 8 hours instead of 24. Measured friction coefficients are no longer converted into braking action, and the runway state group has gone from the METAR.

The definitions moved with it. The damp runway, on which EU-OPS allowed dry performance, no longer exists: any visible dampness, or water up to 3 mm deep, makes the runway wet. The concession that treated a grooved or porous friction course runway as effectively dry has also gone. Part-CAT also requires a check in flight: under CAT.OP.MPA.303 the commander continues the approach only if the landing distance available is at least the landing distance at time of arrival, and the AMC expects a 15 per cent margin (see wet and contaminated runways).

NAT HLA and other airspace changes

On the North Atlantic, the minimum navigation performance specification airspace (MNPSA) became the NAT High Level Airspace (NAT HLA) on 4 February 2016. It extends from FL285 to FL420 inclusive, excludes the Shannon and Brest oceanic transition areas, SOTA and BOTA, and includes Bodø Oceanic, which MNPS airspace did not. ICAO NAT Doc 007 replaced the MNPS operations manual, the approval is still flagged by X in Item 10a of the flight plan, and the operator holds it as a specific approval in its operations specifications. Other NAT changes since then:

• The strategic lateral offset procedure allows offsets right of the centreline in steps of 0.1 NM up to 2 NM (NAT Doc 007, since 2019), where older texts give only 1 NM or 2 NM right.
• The Blue Spruce routes for aircraft with a single long-range navigation system were withdrawn on 20 March 2025.

In European airspace the Standardised European Rules of the Air (SERA), Regulation (EU) No 923/2012, were amended by Regulation (EU) 2024/404 from 1 May 2025. After a radio failure in IMC, an IFR flight now keeps its last assigned speed and level, or the minimum flight altitude if higher, for 20 minutes whether or not ATS surveillance is in use (SERA.14083), where the older rule gave 7 minutes in surveillance airspace; an IFR flight that continues in VMC to land at the nearest suitable aerodrome squawks 7601. ATS must now be told of a change in cruising speed of Mach 0.02 or 10 kt TAS (formerly 5 per cent of the TAS); a revised estimate is due when an estimate is more than 2 minutes in error, where older texts give 3 minutes. On the ground, the ACR/PCR method replaced ACN/PCN for reporting pavement strength on 28 November 2024. See also oceanic and North Atlantic operations and radio communication failure.

Reading older texts and exam questions

Question banks keep EU-OPS figures because examiners still ask for them, normally with a label: "under EU-OPS", "before October 2022", "under the former rules". When a question carries such a label, answer with the old rule; when it names Part-CAT, a current rule reference or nothing at all, use the current one.

Two areas still lean on the older material. The flight time limitation scheme of ORO.FTL and CS FTL.1 covers scheduled and charter operations by aeroplane, while air taxi, emergency medical and single-pilot operations remain under EU-OPS Subpart Q and national rules for now (see flight time limitations). And the mass and balance rules of CAT.POL.MAB are so close to EU-OPS Subpart J that many textbooks still teach them under the old name.

Library articles are written for study and exam preparation. They do not replace your aircraft's approved documentation, your operator's procedures or the regulations themselves.