Overview
EN ISO 8847:2021 - Small craft: Steering gear - Cable over pulley systems specifies design, installation and testing requirements for cable-over-pulley steering systems used on small craft. It covers systems that transmit steering inputs from the helm to the rudder shaft or outboard engine steering arm, including both pedestal and bulkhead installations. The standard applies to small craft with or without propulsion and explicitly includes craft with outboard engines up to and including 37 kW total power. It does not address emergency steering or propulsion control systems.
Key topics and technical requirements
- Scope and applicability: Requirements for all components from the steering mechanism (helm) to the mechanical interface with the rudder or outboard engine; applies to cable-over-pulley and cable-in-conduit variants where relevant.
- Definitions and terminology: Clear definitions for terms like cable, cable drum, steering arm, fairlead, minimum retained system performance, and total steering loss.
- Design requirements: Mechanical integrity of pulleys (swivel and fixed strap types), cable selection, steering arm arrangements, and interfaces with rudder shafts and outboard engines.
- Installation requirements: Guidance for pedestal and bulkhead mounting, routing of cables and fairleads, and accessibility for inspection and maintenance.
- Testing requirements: Factory and in-situ tests to verify strength, performance and minimum retained system performance after test loads (including guidance in informative Annex B for tangential load tests on outboard applications).
- Documentation: Requirements for owner’s and instruction manuals (training, maintenance and inspection instructions).
- Normative references: Includes referenced standards such as ISO 2408:2017 (steel wire ropes).
- Regulatory relationship: Informative Annex ZA maps EN ISO 8847:2021 to essential requirements of Directive 2013/53/EU, offering a route to presumption of conformity where applicable.
Applications and who uses this standard
EN ISO 8847:2021 is intended for:
- Marine equipment manufacturers designing cable-over-pulley steering gear
- Boat builders and naval architects specifying steering systems for small craft
- Installers and service technicians responsible for correct routing, mounting and testing
- Test labs and conformity assessors verifying compliance and performing strength/performance tests
- Regulators and certification bodies assessing conformity with EU recreational craft rules
- Owners and operators consulting owner’s manual requirements for safe operation and maintenance
Practical uses include designing compliant steering systems, selecting appropriate cables and pulleys, performing installation checks, running strength and performance tests, and preparing required documentation.
Related standards and references
- ISO 2408:2017 (Steel wire ropes) - referenced normative document.
- Directive 2013/53/EU - Annex ZA explains how EN ISO 8847 supports essential requirements for recreational craft in the EU.
Keywords: EN ISO 8847:2021, small craft, steering gear, cable over pulley systems, outboard engine, installation, testing, design requirements, owner’s manual.