Basic reference is made to:

  • UK standards for offshore helicopter landing areas published in CAP 437.
  • Norwegian Requirements published in BSL D 5-1.8.2.

The HMS shall accurately process and integrate information from sensors for helideck movement, wind and other meteorological data, which shall be located in optimum positions in order to provide the required information relating to the helideck.

The measuring equipment shall provide sufficient information to the operator to complete all applicable weather sections of the standard offshore weather / helideck report, provided to the helicopter operators.

All information shall be numerically displayed in relevant locations on the vessel or installation for easy communication with helicopters in flight and the helicopter land base operations. The system shall facilitate transmittal of electronic data to the helicopter land base.

Accuracy of measurements

The monitoring system (including related sensors) shall be checked and verified for accuracy and correct operation in accordance with the manufacturer’s procedures following installation – see Section 8.3.

A verification report shall be provided to both the owner of the installation, the helicopter operator(s) and the Helideck Certification Agency.

The accuracy of the system shall be checked and verified whenever deemed necessary, as required by the manufacturer’s procedures or every 2 years, whichever the sooner.

A verification report shall be issued and distributed after each periodic control.

The accuracy concerning meteorological data other than wind speed and direction shall be in compliance with CAP 437 Standards for offshore helicopter landing areas published by the UK Civil Aviation Authority or equivalent national standards.

The accuracy of the data produced by the Helideck Monitoring System concerning motion shall be:

  • Pitch / Roll / Inclination: <± 0.1° RMS (Root Mean Square) in the range 0 to 3.5°
  • Heave Rate: < ± 0.1 m/s RMS (Root Mean Square) in the range 0 to 1.3 m/s,
  • Helideck Accelerations (MSI): < ± 0.01 m/s2 RMS (Root Mean Square) in the range 0 to 0.2 m/s2 .
  • Wind Speed: Under 10 kts: +/-1kt, over 10kts: 10%,
  • Wind direction (relative to magnetic North) overall accuracy of better than +/-10deg for wind speeds over 2kts. This will depend not only on the measurement accuracy of the wind sensor, but also on the accuracy of the orientation of the wind sensor relative to the vessel, and the accuracy of the vessel heading measurement relative to magnetic North.



The following items are fully defined and form firm requirements:

  1. All lighting components should be tested by an independent test house. The photometrical and colour measurements performed in the optical department of this test house should be accredited according to the version of EN ISO/IEC 17025 current at the time of the testing. The angular sampling intervals should be: every 10° in azimuth; every 1° from 5° to 15° and every 5° from 15° to 90° in elevation.
  2. All intensities shall be measured in accordance with the test procedures for helideck status lights contained in Appendix B of CAA Paper 2008/01. The modified-Allard method (see Appendix C of CAA Paper 2008/01) shall be used for calculation of the effective intensity.

Other considerations

The considerations detailed in this section are presented to make equipment designers aware of the operating environment and customer expectations during the design of the products/system. They do not represent formal requirements but are desirable design considerations of a good lighting system:

  1. All lighting components and fitments should meet safety regulations relevant to a helideck environment such as explosion proofing (Zone 1 or 2 as appropriate) and flammability and be tested by a notified body in accordance with the ATEX directive or equivalent locally applicable hazardous area certification standards.
  2. All lighting components and fitments should meet IEC International Protection (IP) standards according to IEC 60529 appropriate to their location, use and recommended cleaning procedures. It is expected that this will entail meeting at least IP66 (dust tight and resistant to powerful water jetting).
  3. Control panels that may be required for helideck lighting systems are not covered in this document. It is the responsibility of the Duty Holder / engineering contractor to select and integrate control panels into the installation safety and control systems, and to ensure that all such equipment complies with the relevant engineering standards for design and operation.
  4. The system and its constituent components shall also comply with all regulations relevant to the installation.

More Information

Back to the CAP 437 overview or take a look at version 8c details.

Please contact us for discussing a recommended service routine for your systems, upgrade or you are looking at a completly new system to be deployd.

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Helideck Monitoring Systems
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Offshore Installation and Commissioning Services

WISE Group has a well qualified team of field service engineers who can undertake service work on all kinds of meteorological and oceanographic sensors and systems.

All our engineers have extensive experience from offshore work, shipyard work and onshore work.

Operation and Maintenance Services

WISE Group team of field service engineers can also undertake operation and maintenance services work on MetOcean sensors and systems as well as on other kinds of sensors and systems.

Our engineers can take care of preparing operation and maintenance services schedules, carry out maintenance visits, analyse data, service equipment and many other related tasks.

WISE Group can also offer online preventive service agreements for systems that can be reached online.

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WISE Group are also able to service and calibrate all kinds of sensors and MetOcean equipment used in offshore renewable projects.

Our workshop is equipped for servicing and calibrating many different kinds of sensors and instrumentation.

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WISE Group can take full responsibility for all aspects of offshore instrumentation projects from design of the system, engineering, system integration, installation, commissioning, operation and maintenance to data management.