Deck Inclination and Rate of Heave of a moving Helideck are of paramount importance to a Helicopter crew when trying to land on the Helideck. Civil Aviation Publication 437 (CAP437) ‘Helicopter Landing Areas – Guidance on Standards’ details the regulations regarding Helideck Movement:
‘Pitch and roll reports to helicopters should include values, in degrees, about both axes if the true vertical datum (i.e. relative to the true horizon) and be expressed in relation to the vessel’s heading. Roll should be expressed in terms of ‘left’ and ‘right’; pitch should be expressed in terms of ‘up’ and ‘down’; heave, being the total heave motion of the Helideck, should be reported in metres. Heave is to be taken as the vertical difference between the highest and lowest points of any single cycle of the Helideck movement. The parameters reported should be the maximum peak values recorded during the 20 minute period prior to commencement of helicopter deck operations. Values of pitch, roll and heave should be reported to one decimal place.’
Harmonisation between those criteria and Norwegian standards has seen further amendments released by the Helideck Certification Agency (HCA) in a document entitled ‘Standard Measuring Equipment for Helideck Monitoring systems (HMS) and Weather Data’. This expands the criteria issued in CAP437 and gives detailed information on the parameters that should be measured.
Muir Matheson’s HMS is fully compliant with both CAP and HCA regulations and can be fitted to any vessel.