Under keel clearance

Under keel clearance (UKC) is the term and calculations used in seafaring to ensure sufficient navigable water is available for ships at sea.[1][2][3][4] It is most commonly described as the height and width of available water below the keel (hull of a ship).[3][5] More simply, it can be described as how much water is left between the bottom of the ship and the seabed.[6]

Master mariners should ensure there is sufficient minimum UKC for their ships and ports should ensure sufficient minimum UKC for the type and draft of ships due to arrive in the port.[7][6] Ships typically calculate their UKC to meet criteria for ports to minimise the risk of maritime incidents.[6] A minimum UKC value is determined, which includes a safety margin.[7]

  1. ^ Gilardoni, Eduardo O.; Presedo, Juan P. (2017). Navigation in Shallow Waters. Livingston, Scotland: Witherby Publishing Group. p. 67. ISBN 978-1-85609-667-6.
  2. ^ ECDIS Safety Settings and UKC Management. Livingston, Scotland: Witherby Publishing Group. 2017. ISBN 9781914993695.
  3. ^ a b Weintrit, Adam (2009-06-02). Marine Navigation and Safety of Sea Transportation. Boca Raton : London: CRC Press. p. 484. ISBN 978-0-203-86934-5. OCLC 435419166.
  4. ^ "What Is Underwater Keel Clearance?". Marine Insight. Retrieved 4 April 2024.
  5. ^ "Simplified approach to operationalise UKC calculations Conference Paper". PIANC. Retrieved 4 April 2024.
  6. ^ a b c "All you ever wanted to know about Under Keel Clearance but were afraid to ask". Nautical Institute. Retrieved 4 April 2024.
  7. ^ a b ECDIS Passage Planning and Watchkeeping. Livingston, Scotland: Witherby Publishing Group. 2023. p. 25. ISBN 9781856098168.