This article addresses aspects of the use of ECDIS in ships, drawing on a report about confusion between chart variants within a single ship’s system, brought to light when passage planning.
What did the reporters tell us?
During preparation of a passage plan for a forthcoming voyage, it was observed that one chart did not show all the information that had been seen when passing through the Suez Canal previously. There emerged considerable confusion on the source, date and identity of the right chart within the ship’s system. Space prevents detailed coverage. Eventually the correct electronic chart was identified by the ship’s provider, and supplied.
One supplier’s chart
Another supplier’s chart
The Passage Manager page
The lessons to be learnt
This article acknowledges and draws on the UK Nautical Institute’s “The Navigator” Issue 5, 2014, titled ECDIS.
Electronic Chart Display and Information Systems (ECDIS) are now widespread, but not yet universal. Younger seafarers might take them in their stride; older ones may feel discomforted without paper charts which they know from long experience they can interpret at a glance.
Standards and training. This article exclusively addresses IMO approved ECDIS. There are other less capable and unlicensed Electronic Chart Systems (ECS) which should not be used. In 2014, according to The Navigator (Issue 5), there were over 30 ECDIS manufacturers in operation. Their systems are far from standardised. This implies a major familiarisation task for navigators and Masters who may alternate relatively rapidly between different systems. A considerable number of accidents or near misses have been found to result from misuse of ECDIS, rather than from design failures. High quality training, meeting the requirements of the IMO model course, is essential. So is structured familiarisation with the capabilities and limitations of individual systems, accompanied by constant practice. The uses of ECDIS include active navigation (with or without automated satellite positioning input), pilotage planning and execution, and passage planning.
Passage planning. Failures in the past have resulted from errors such as the incorrect application of safety depths, safety contours, or alarms. Vessels’ data (especially draught) may have also been incorrectly entered, and automatic route check facilities may not have been used. Failure to check that charts are up to date, possibly through lack of familiarity with the automatic or manual correction procedures, presents serious risk, as it always has in the past. Passage planning should also be carried out on charts at scales which allow identification of the necessary levels of detail. Final visual checks along the whole of the tracks before voyages are essential, on the lookout for obstructions, shallows, traffic management systems and the like. In addition broader checks along tracks designed to identify areas of high shipping density or strong tidal streams for example (cases which may not be immediately apparent from the automated information) should also be made. The whole should then be briefed.
Increasingly, chart supply companies offer proprietary Back of Bridge Passage Planners to plan routes, and manage chart orders to cover these. The Appraisal, Planning, Execution, Monitoring (APEM) model (IMO Resolution A.893(21)), guidance on use of ECDIS (NP232) which adds a specific Review step to give APREM, and NP231 (electronic navigational charts – ENC) are essential reading. The appraisal phase should ensure that both the Planning Station and the ECDIS are updated to the latest catalogue provided by the chart supplier, while ensuring that the latest ENC updates are available.
For such a change to charting as identified in this case, UKHO Notice to Mariners (NtM) would inform users that the GB cells covering the Suez Canal were being cancelled and that they were to be replaced with Egyptian cells. This gives the mariner the advanced notice needed to remove superseded cells from ECDIS, and to order the necessary replacements when required for planning. Thus taut configuration control can be maintained. Less obvious to the modern ECDIS navigator might be the requirement for all transiting vessels to carry Egyptian issued paper charts for the Suez Canal, even if they are a fully digital navigation platform. Assessing all information here would include reading the latest SCA navigation circulars, where this information would be available, as well as NtM Section VIII for withdrawn and cancelled ENCs.
Active navigation, including pilotage. Many of the comments on ‘passage planning’ apply. It is well known that too small a chart scale may conceal crucial information including shoal depths and routeing information. Both visual and radar fixes can be plotted on ECDIS charts in ways analogous to the paper method, and as quickly; but only – as in everything – with practice. It is essential – when conditions are benign – to practise the old skills as applicable to ECDIS. One day they will be needed, almost invariably in testing circumstances. Finally, use all equipment in the role that each piece is designed; for example an ECDIS display with an AIS overlay is not designed for collision avoidance.
The old and the new. Many of today’s potential electronic errors are just the current versions of the ones we knew with paper charts. For example, the correctly scaled and corrected charts were always crucial. Nowadays a generation of navigators used to Google maps may be tempted to unquestioning belief in the infallibility of information on screens, especially on bridges equipped with more automated information than ever before. This would be a grave mistake. On the other hand, younger practitioners can help older ones to learn and trust the new systems.
A fundamental principle of all aspects of navigation has always been the double-check; an inalienable instinct to question and to use all sources of information available. Does the depth tie in with the chart, and with the ECDIS position, and with radar information and with the ship’s estimated position, for example? If the answer is yes, all is likely to be well; if not, something is likely to be wrong. Always clarify what that ‘something’ is, slowing down, stopping or re-checking as appropriate.
Finally we must in 2016 confront the cyber threat; by no means is the maritime environment exempt. GPS signals can be corrupted, and ECDIS systems can be subjected to attack. This puts a double premium on the double-check. See an article by Andy Norris in Digital Ship that develops this topic: http://www. thedigitalship.com/component/downloads/send/13-2015/1984-digital-ship- 109-august-2015. No one wants to run his ship aground through the unseen insertion of malware, when a second glance out of the window would have put him right.
CHIRP suggests that training, familiarisation and practice are crucial. Take time to read and understand instructions and advice (see some of the sources listed above). Know your equipment. ECDIS displays don’t necessarily have to have a GPS input; they can be used exactly as paper charts have been, if necessary. The principles of safe navigation haven’t changed; just the means by which some of our information is displayed. Don’t trust automated displays, without a healthy instinct to cross- check. Remember the age old, gilt-edged, adage: “use all sources, and double check everything”. Keep on top of your configuration control.