Check and declare fishing vessel engine power

Engine manufacturers' database and guide for builders, owners, skippers, managers, surveyors and measurers of UK registered fishing vessels.


FV Engine power January 2015

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Declaring MCEP

Maximum continuous engine power (MCEP) is the total power that can be obtained at the flywheel of each engine that’s used to propel your fishing vessel.

You must declare the MCEP or permanently de-rated engine power when registering or re-registering your vessel with the Registry of Shipping and Seamen (RSS). MCA surveyors check the MCEP as part of a vessel’s survey or inspection.

How to check an engine’s MCEP

There are various ways to find out the MCEP of your engine(s). You can:

  • check the MCA fishing vessel engine manufacturers’ ‘database’
  • contact the Registry of Shipping and Seamen (RSS)
  • contact your local marine engineer
  • contact the MCA marine office nearest to your vessel’s port of registry

De-rated engine power – inboard engines only

Owners who want to de-rate engine power must first advise the Marine Management Organisation (MMO) or their devolved fisheries authority in Scotland, Northern Ireland or Wales.

Outboard motors

You can’t de-rate outboard motors any longer. You must register your vessel using the engine manufacturers specified power output. Existing registered vessels with de-rated outboards can keep their declared engine power but may be subject to engine power tests.

Further information

You can find more detailed guidance in the marine guidance note MGN 435 (F).