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Navigation at sea with ECDIS advantages, drawbacks, and requirements

The tools we use to navigate the seas continue to change as advancements in technology allow us to create new systems that make navigation easier, safer, and create consistency. For the past 200 years, the National Oceanic and Atmospheric Administration (NOAA) has produced the nautical charts that navigational officers would use to update their paper charts. Today, paper charts are becoming a thing of the past as new systems like the ECDIS become the standard for navigation.

What is an ECDIS SYSTEM?

An ECDIS, Electronic Chart Display and Information System, is a navigational tool that runs on a geographic information system that conforms to the International Maritime Organization (IMO) as a replacement for paper charts. With an ECDIS display, a ship’s navigating crew now has an easier time pinpointing locations and obtaining directions with the help of the electronic chart system.

The advantages of these systems include enhanced safety and the ability to incorporate more information compared to other navigation tools. ECDIS units also help automate numerous tasks such as ETA computation, ENC updating, and route planning and monitoring to ease the navigator’s workload.

The ECDIS works by incorporating traffic routing systems (GPS), RADAR, coastline information, units of depth and height, Echo sounder, ARPA (Automatic Radar Plotting Aid), and other navigational equipment incorporating all of this information to give ship navigators the necessary information for their voyage. Although these systems are of great help, your ECDIS unit must comply with certain regulations.

An ECDIS unit can be used as a primary means of navigation as long as the unit is approved and certified as complying with the International Maritime Organization’s (IMO) standards.

ECDIS Display Requirements and Regulations

The International Maritime Organization (IMO) is in charge of ECDIS standards. These Performance Standards were adopted by the International Maritime Organization (IMO) on November 23, 1995, and published as IMO Resolution A19/Res.817.

Electronic Chart Display and Information Systems must adhere to specific regulations to be used as an alternative to paper charts; some of those regulations include:

  • Under regulation V/20 of the 1974 SOLAS Convention, it is required that a system have adequate backup arrangements and up-to-date charts.
  • It is required that a system display all chart information that government-authorized offices deem essential to safe and effective navigation.
  • The system should make updating the electronic navigational chart reliable and straightforward.
  • With ECDIS, the navigational workload should be reduced compared to paper charts. The mariner should also be able to plan, monitor, and position all routes conveniently and timely, currently carrying out functions on paper charts.
  • A warning or alarm should be provided when there is a malfunction in the equipment or when the information displayed is incorrect.
  • ECDIS should be able to plot the ship’s position continuously and perform all route planning, monitoring, and positioning a paper chart would do.
  • ECDIS systems are certified as a complete system by individual classification societies
    such as the American Bureau of Shipping (ABS), Lloyds Register, Bureau Veritas, DNV,
  • RINA and many additional international registers.

Other requirements

Certain vessels are mandated to have ECDIS units onboard and cannot undertake an international voyage unless they use an ECDIS. According to the International Maritime Organization (IMO), the amended SOLAS regulation V/19, all newly built passenger ships, 500 gross tonnage and up and new cargo ships of 3,000 gross tonnages and up must be fitted with an ECDIS unit for international travel.

Older vessels engaged in international voyages and are of a specific size must also fit ECDIS units onboard.

Types of charts an ECDIS unit can display

An ECDIS system can display two types of charts; these electronic charts include Raster Chart (RNC) and Vector Chart (ENC).

  • RNC: Raster Navigational Charts are original paper charts scanned to be viewed in an electronic format. You can add information such as geographic points in real-time, making it easy for mariners to identify and analyze information on the chart. Again, RNCs are simply digitizing the paper chart with no additional data features, so there will naturally be some disadvantages when an ECDIS is operating under RNC mode.
    • Charts are scanned in digitally and have a limited resolution. The more you zoom in, the more the image becomes blurry and more difficult to see details.
    • Operation in RNC mode provides limited warning functionality. Although automatic alarms can’t be triggered in RNC mode, the system can still offer some warning based on the entered information. Those alarms include danger areas, isolated dangers, ship safety contour lines, and clearing lines.
    • Readability may be compromised in Raster Navigational Charts as text may appear sideways when zooming in.
  • ENC: An Electronic Navigational Chart (also known as a vector chart) provides more information than a Raster Chart. These charts are computer-generated, and each object on the chart can be clicked on to reveal more information. Many mariners whose ships are equipped with ECDIS prefer to operate their systems under ENC mode. Although this mode is preferred by many, it is essential to keep in mind that there are some locations out at sea where vector (ENC) charts are not available.
    • With ENC charts, you may zoom in and out without losing image quality; this gives mariners an advantage over Raster Charts because they can zoom out and view the route ahead.
    • Due to the increased amount of data available, vector charts can provide warnings, improving the safety of navigation. The ECDIS can provide several types of warnings, including shallow depth, isolated dangers, cross-track errors, approaching waypoints, and anti-grounding alarms if the vessel’s echo sounder enters data into the system.

ECDIS chart updates may reach the vessel through various channels depending on onboard communication capability.

  • Information can be received through physical media like DVDs, memory USB storage devices, or via internet connectivity.
  • SATCOM, email attachment
  • With certain software, it is also possible to receive updates via SATCOM broadcast messages.

In what ways does an ECDIS unit perform better than a paper chart?

  • ECDIS allows the user to set a variety of alarms and warnings.
  • RADAR can be used to monitor targets continuously.
  • Monitoring of the ship’s position continuously.
  • ECDIS can be used to plan passages without consulting other publications.
  • Due to other navigational data on the ECDIS, the passage progress can be tracked more rigorously.
  • The speed and accuracy of ECDIS allow navigating officers to plan their voyages much faster than on paper charts; most systems can import data into a spreadsheet format which helps to reduce the manual effort of inputting waypoints.
  • ECDIS is interconnected with the vessel’s independent GPS transceivers, so the system functions even if the navigator fails. Remember that GPS signals can sometimes be unreliable and prone to errors.

What are the drawbacks of using an ECDIS unit?

  • The ease of use and influx of information may cause over-reliance, leading to disastrous results. It’s essential to keep in mind that an ECDIS unit is there to facilitate navigation and should never be used as a replacement or substitute for essential navigation skills.
  • An ECDIS unit is just as good as the information it receives; wrong inputs, loss of signal, or missed alarms can lead to dangerous situations.

ECDIS unit training requirements

Navigational officers must undergo training if they are sailing on a vessel that is fitted with an ECDIS unit. It does not matter if the system is not a vessel’s primary source of navigation; if the vessel is equipped with an ECDIS, training is required.

ECDIS display color calibration

ECDIS displays must be calibrated to meet specific color codes and guidelines. All ECDIS displays must use the same color codes to identify symbols (such as buoys, water depth, etc.) on the charts. The performance of these displays is based on their ability to reproduce the exact red, blue, and green color values (RBG) and luminance output. It is instrumental to the safety of those on board as well as those out at sea that the color representation of each display is correct to minimize the possibility of human error.

How are the displays calibrated? Two processes can be used to calibrate a display:

  1. A color correction table can be produced for the display and stored in the memory; later the electronic display system will be able to download the table and use it to make corrections on the ECDIS system.
  2. The second process includes two tests; one test is completed on the ECDIS display, and then tested against a reference image to achieve the correct color values.

Seatronx offers ECDIS commercial displays designed to meet International Maritime Organization (IMO) compliance regulations.

These displays are color calibrated for optimal electronic chart viewing with capacitive touch keys for quick function access and display control (Support Ecdis Day, Dusk, and Night Mode Switching). Meets The Requirements Of Industrial Marine Standards, Including IEC60945 4th Edition, DNVGL-CG-0339, IACS E10.

CD Series

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