Yacht engineer CoCs: the Small Vessel route, plainly.

What replaced the Y4–Y1 yacht engineer certificates?

MSN 1904 replaced MSN 1859 (Amendment 1) on 10 January 2023. The MSN 1859 yacht route closed on 31 December 2022, after which no further Notices of Eligibility (NOEs) were issued for those yacht orals. The MCA's engineering guidance puts it plainly: 'The yacht structure has closed - no further NOEs will be issued (except resits).'

The yacht-specific route is now the Small Vessel (SV) CoC, which can be used on yachts, tugs, fishing vessels, workboats and the other small vessel types MSN 1904 lists, within the limits printed on the CoC. A merchant engineer CoC at the right level also lets you serve on a yacht.

Which Small Vessel engineer CoCs are there?

Three, all unlimited area. Engineer Officer of the Watch (EOOW), less than 9,000 kW and less than 3000 GT, issued at operational level. Chief Engineer, less than 3000 kW and less than 500 GT. And Chief Engineer, less than 9,000 kW and less than 3000 GT. The two Chief Engineer CoCs are issued at management level; MSN 1904's certificate table places them under STCW regulations III/3 and III/2 respectively, and the EOOW under III/1, each alongside Chapter VII.

kW means the vessel's main propulsion power unless stated otherwise.

Can I get a Small Vessel CoC limited to yachts?

Yes. Engineers working on yachts can apply for an SV CoC restricted to yachts. It carries the SV limits plus a yacht limitation — MSN 1904's example is 'Less than 9000 kW, Less than 3000GT, Unlimited Area, Limited to Yachts'. Its sea time requirements differ from the unrestricted CoC; our engineer sea time guide sets out both.

What are the routes to the Small Vessel EOOW CoC?

You must be at least 18 and follow one of three routes. The standard route is an MCA-approved programme built around the Diploma in Maritime Studies: Small Vessel Engineer — but the MCA's engineering guidance says no training providers currently offer it. The Experienced Seafarer route is for people already serving on small vessels. The Alternative route is for holders of a relevant engineering degree, HND, HNC or equivalent, or an engineering apprenticeship at NVQ level 3 or above.

The MCA's guidance is to read MSN 1904 and MIN 642, then contact an MCA-approved Small Vessel Engineering training provider to enrol and get an action plan — and not to apply for exemptions before you have one. The NOE application itself is on form MSF 4900, emailed to the MCA's engineering team.

What does the Experienced Seafarer route require?

To register with an MCA-approved SV training provider: 24 months' onboard service, including 6 months' seagoing service in the engineering department, on vessels of at least 200 kW; Approved Engine Course (AEC) I and II; and the four basic STCW safety certificates (survival, fire fighting, first aid, and personal safety and social responsibilities). Engine room service of cleaning duties only isn't accepted.

Once registered you're issued a Training Record Book (TRB). Before your NOE you then need a further 11 months' seagoing service on vessels of at least 350 kW, including at least 6 months on watchkeeping or UMS (unmanned machinery space) duties; 2 weeks' MCA-approved initial Workshop Skills Training; and either 2 more weeks' seagoing service on 350 kW+ vessels or 2 weeks' additional Workshop Skills Training. TRB tasks and this sea time only count once you have registered; time on yachts is counted as our engineer sea time guide explains.

What about the Alternative route for engineering graduates?

You apply straight to an MCA-approved SV training provider for an Action Plan. Every candidate does 6 months' seagoing service on watchkeeping or UMS duties on vessels of at least 350 kW, recorded in a TRB, then further seagoing service on 350 kW+ vessels: 5 months for a graduate, HND holder or NVQ level 3 apprentice, 8 months for an HND student and 11 months for an HNC holder — each plus 2 weeks' more sea time or additional Workshop Skills Training. AEC I and II and the initial Workshop Skills Training are also required.

Which exams does the EOOW need?

Three MCA Small Vessel Competency examinations, each after its MCA-approved module: Marine Diesel Engineering; Auxiliary Equipment – Part I; and Operational Procedures, Basic Hotel Services and Ship Construction. Then the ancillary and safety certificates for the CoC (HELM at operational level among them), a valid ENG1, and the EOOW oral.

What do I need for Chief Engineer <3000 kW, <500 GT?

While serving on your SV EOOW CoC, at least 6 months' seagoing service as EOOW on vessels of at least 350 kW. Then the modules and exams in Chief Engineer Statutory and Operational Requirements and Auxiliary Equipment – Part II, the ancillary and safety certificates (including HELM at management level), and the oral for this CoC. If your service is on yachts, MSN 1904's yacht table counts it differently. Our engineer sea time guide sets it out.

And Chief Engineer <9,000 kW, <3000 GT?

While serving on your SV EOOW CoC — time on the <500 GT Chief Engineer CoC is also accepted — at least 12 months' seagoing service as an SV EOOW engineer: 6 months on vessels of at least 750 kW and 6 months on vessels of at least 350 kW. Then Applied Marine Engineering and General Engineering Science I & II, plus Auxiliary Equipment – Part II and Chief Engineer Statutory and Operational Requirements unless you already hold the <500 GT Chief Engineer CoC, the ancillary certificates, and the oral. A relevant UK engineering degree, HND or HNC may exempt you from General Engineering Science I & II. If your service is on yachts, MSN 1904's yacht table counts it differently. Our engineer sea time guide sets it out.

How long do Small Vessel exam passes last?

Every MCA Small Vessel Competency exam except General Engineering Science I & II, which has no expiry, and the MCA oral must be passed within the 3 years before your CoC is issued. Your NOE is valid for 5 years from issue, and the CoC itself for 5 years from the date you met the qualifying conditions. Your ENG1 must be valid when the CoC is issued.

What should I expect from the Small Vessel oral?

It is based on the MCA's published Small Vessel oral syllabus for your CoC, and MSN 1904 recommends finishing all your education and training first. For the EOOW oral you must be able to provide your Training Record Book on request, and the examiner may refer to it during the exam.

If you fail, you apply for another NOE and pay a resit fee — currently £159, according to the MCA's engineering guidance. For how orals are booked and run online, and the minimum waits between attempts, see our MCA oral exam guide. Part A, the computer-based test described there, doesn't apply to engineer CoCs: you sit the online oral only.

Is my Y4–Y1 yacht CoC still valid?

Existing yacht engineer CoCs can still be revalidated; what has closed is new NOEs on the old structure (except resits). The MCA's yacht engineering page says the new manning requirements in MSN 1868 Amendment 1 should let holders of MSN 1859 yacht CoCs keep working on UK and other Red Ensign Group yachts.

If the MSN 1859 manning table let you work above your CoC's stated capacity and you want to keep working at that level, you must apply to the MCA to have the equivalent capacity and limitation added to your CoC.

How do I convert a yacht CoC to a Small Vessel CoC?

Through the conversions in section 7 of MIN 642; after converting, you progress through MSN 1904. Every conversion needs the ancillary certificates for the new CoC and an ENG1. Beyond that, in outline:

Y4 (Chief Engineer <200 GT, <1,500 kW) to SV EOOW: 6 months' onboard service as Y4, at least 4 of them seagoing on yachts of 350 kW or more. Y4 to SV Chief Engineer <3000 kW, <500 GT: 12 months' onboard service as Y4, at least 6 of them seagoing on yachts of 350 kW or more, then a module, an exam and the oral. Y4 to SV Chief Engineer <9,000 kW, <3000 GT: 12 months' seagoing service as Y4 on yachts of 350 kW or more, including 6 months on yachts of 750 kW or more (which can be from any point in your career), then modules, exams and the oral. Y3 (<500 GT, <3,000 kW) to SV Chief Engineer <3000 kW, <500 GT: nothing more (HELM at management level is among the certificates). Y3 to the <9,000 kW CoC: 12 months' onboard service as Y3 including 6 months' seagoing, or 12 months' seagoing as Y4; 6 months of that seagoing service on yachts of 750 kW or more and the rest on 350 kW or more; then modules, exams and the oral. Y2 (<3,000 GT, <3,000 kW) to SV Chief Engineer <9,000 kW, <3000 GT: 3 months' seagoing as Y2 on yachts of 750 kW or more, and the oral. Y1 (<3,000 GT, <9,000 kW) to the same CoC: nothing more.

All conversions also need 6 months' seagoing service in the last 5 years. MIN 642 states that it expires on 1 December 2025, but the MCA's engineering guidance, updated in October 2026, still sends yacht CoC holders to its section 7 — check the current version before you apply.