An electronic navigational chart (ENC) is an official database created by a national hydrographic office for use with an Electronic Chart Display and Information System (ECDIS).[1] ECDIS and ENCs are the primary means of electronic navigation on cargo ships.[1]

Electronic navigational chart (NOAA)

Inland Electronic Chart Display and Information System are similar systems used for navigation of inland water.

ENC edit

An Electronic Navigational Chart (ENC) is a digital representation of a real-world geographical area for the purpose of Marine navigation. Real-world objects and areas of navigational significance, or to a lesser degree - informational significance, are portrayed through Raster facsimiles of traditional paper charts; or more commonly through vector images, which are able to scale their relative position and size to meet a Mariner's Selected Viewing Scale (MSVS) displayed through an ECDIS.

The first ENC was patented in 1986 by Mortimer Rogoff, Peter Winkler, and John N. Ackley with Navigation Sciences, Inc in Bethesda, Maryland (Patent number: 4590569).[2]

All Navigational charts must meet the requirements set out in the Safety of Lives At Sea (SOLAS) Convention.[3] To meet these requirements, ENC's created and published by a Hydrographic Authority must conform to the internationally recognised standards stated in the publications set out by the International Hydrographic Organization (IHO). Presently the S-57 Standard is the only ENC standard which meets SOLAS chart carriage requirements.[4] The IHO and it's parent body the International Maritime Organization (IMO) have begun a transition to a new suite of standards that is targeted to exist as a unified, interactive suite of products and standards within the S-100 Universal Hydrographic Data Model.[5] Within this model an updated standard for the production and publishing of ENCs is under development; The S-101 product specification.[6] At present Hydrographic Authorities must only produce and publish data to the S-57 product specification, from here that published data can be certified as an ENC.[7] Only ENCs can be used within ECDIS to meet the International Maritime Organization (IMO) performance standard for ECDIS.[7]

ENCs are available for wholesale distribution to chart agents and resellers from Regional Electronic Navigational Chart Centres (RENCs). The RENCs are not-for-profit organizations made up of ENC-producer countries. RENCs independently check each ENC submitted by the contributing countries to ensure that they conform to the relevant IHO standards. The RENCs also act collectively as one-stop wholesalers of most of the world's ENCs.

IHO Publication S-63 developed by the IHO Data Protection Scheme Working Group is used to encrypt and digitally sign ENC data. Chart data is captured based on standards stated in IHO Publication S-57, and is displayed according to a display standard set out in IHO Publication S-52 to ensure consistency of data rendering between different systems.

IMO adopted compulsory carriage of ECDIS and ENCs on new high speed craft from 1 July 2010 and progressively for other craft from 2012 to 2018.[8]

ECDIS edit

 
An ECDIS using ENCs on a merchant ship

An Electronic Chart Display and Information System (ECDIS) is a geographic information system used for nautical navigation that complies with International Maritime Organization (IMO) and IHO regulations as a method of electronic navigation.[9] It is considered as an alternative to paper nautical charts for navigation by ships.[9] IMO refers to similar systems not meeting the regulations as Electronic Chart Systems (ECSs).[10]

An ECDIS system displays the information from Electronic Navigational Charts (ENC) and integrates position information from position, heading and speed through water reference systems and optionally other navigational sensors. Other sensors which could interface with an ECDIS are radar, Navtex, Automatic Identification Systems (AIS), and depth sounders.

In recent years concerns from the industry have been raised as to the system's security especially with regards to cyber attacks and GPS spoofing attacks.

ECDIS provides continuous position and navigational safety information. The system generates audible and/or visual alarms when the vessel is in proximity to navigational hazards. Military versions of ECDIS are known as WECDIS (warship ECDIS) or ECDIS-N (ECDIS-naval).[11]

Regulations edit

ECDIS (as defined by IHO Publications S-57 and S-52)[12] is an approved marine navigational chart and information system, which is accepted as complying with the conventional paper charts required by Regulation V/19 of the 1974 IMO SOLAS Convention.[13] as amended. The performance requirements for ECDIS are defined by IMO and the consequent test standards have been developed by the International Electrotechnical Commission (IEC) in International Standard IEC 61174.[14]

S-100 edit

In the future, the ENC will be part of a product specification family which is based on the "IHO Universal Hydrographic Data Model", known as S-100. The product specification number S-101 has been assigned to the ENC.[12][7] ENCs are now being produced under the S-100 standard and it is envisaged that S-100 ENCs will replace S-57 data sets by the 2030s.[15] The new ENC standards include greater data layers allowing for enhanced navigation formats, such as S-129 on Under Keel Clearance Management (UCKM).[15] Other sub-formats include S-102 on Bathymetric Surfaces, S-111 on Surface Currents and S-124 on Navigational Warnings.[15]

See also edit

References edit

  1. ^ a b ECDIS Procedures Guide. Livingston: Witherby Publishing Group. 2021. p. ix. ISBN 9781914992049.
  2. ^ Matt Schudel (August 17, 2008). "Mortimer Rogoff Inventor and Businessman". The Washington Post. Washington, DC. Retrieved December 27, 2023.
  3. ^ https://iho.int/uploads/user/Services%20and%20Standards/ENC_ECDIS/PSC%20Advice%20IHO_Ed%202.1_Final.pdf
  4. ^ https://iho.int/en/standards-in-force
  5. ^ https://iho.int/en/s-100-universal-hydrographic-data-model
  6. ^ https://registry.iho.int/productspec/view.do?idx=195&product_ID=S-101&statusS=5&domainS=ALL&category=product_ID&searchValue=
  7. ^ a b c ECDIS Passage Planning and Watchkeeping. Livingston: Witherby Publishing Group. 2022. p. 5. ISBN 9781914992599.
  8. ^ "Towards ECDIS Mandatory Carriage". Hydro International. Archived from the original on 2007-09-29. Retrieved 2007-09-02.
  9. ^ a b ECDIS Passage Planning and Watchkeeping. Livingston: Witherby Publishing Group. 2022. p. 4. ISBN 9781914992599.
  10. ^ "ENCs, ECDIS & S-100". International Hydrographic Organization. Archived from the original on 6 February 2015. Retrieved 2010-07-13.
  11. ^ "WECDIS Military Training – Home of the Naval ECDIS Community". Archived from the original on 30 October 2016.
  12. ^ a b "IHO - Publications /OHI - Publications". International Hydrographic Organization. Retrieved 2010-07-13.
  13. ^ "Charts". International Maritime Organization. Archived from the original on 2015-07-16. Retrieved 2007-09-01.
  14. ^ "Maritime navigation and radiocommunication equipment and systems – Electronic chart display and information system (ECDIS) – Operational and performance requirements, methods of testing and required test results". International Electrotechnical Commission in the woeld. Retrieved 2007-09-01.
  15. ^ a b c ECDIS Procedures Guide. Livingston: Witherby Publishing Group. 2021. p. 16. ISBN 9781914992049.

Further reading edit

External links edit