What is an ECDIS And How It Works



At the turn of the century, ships still relied on paper charts, as they had for hundreds of years. At the time, sailors could hardly imagine a change in this foundational tradition. Fewer than 20 years later, every significant ocean voyage incorporates the guidance of an electronic chart display and information system. Navigational officers have quickly grown familiar with the system, but a new navigator or hobbyist might not know about it. For these people, the most pressing question is, "What is an ECDIS?"


What is an ECDIS?

The Electronic Chart Display and Information System is a specialized digital navigation computer, and an alternative to paper charts. It stores a set of Electronic Navigation Charts (ENCs) and/or Raster Charts, which can display all the necessary geographic information a crew needs to complete a voyage. However, an ECDIS isn't simply a digitized replacement for traditional charts.

ECDIS charts typically incorporate much more information than past navigation tools, and automate many essential functions. For instance, the navigator now has a much lighter burden thanks to automatic route planning and monitoring. While route correction once consumed much of a navigation officer's time, it's a thing of the past with a working ECDIS. The precision, consistency and reliability of electronic navigation represents a boon to safety, efficiency and profitability.

How ECDIS Works

The ECDIS works by incorporating robust, specialized electronic navigation software with many modern navigational tools. This includes fixtures such as GPS, RADAR, ARPA and numerous others. You can use your ECDIS to access information from these sources, check Tide Tables and check virtually all relevant navigational information.

By using ENC's, the ECDIS is able to ascertain precise depth information and early-warning on any potential hazards along the route. A crew can gain even more precise information by calculating and inputting figures such as squat, which can pull a ship closer to the seabed. This information feeds into several other automated functions, providing for extremely accurate route safety judgments and automated safety warnings.

ECDIS Charts

The exact function of an ECDIS depends on the type of charts that a ship is currently using. When a ship deploys the latest electronic navigation charts, it enjoys the full breadth of information, automation and safety features. Sometimes, though, it's necessary to use Raster Charts, which are light on features.

Electronic Navigation Charts (ENC)

An electronic navigation chart, also known as a vector chart, is the primary type of chart that an ECDIS uses. This is a fully modern, digital chart that incorporates all of the advantages of electronic navigation. Computer generation comes with a wealth of data and additional features, such as depth alerts and customizable visuals.

The user can turn certain ENC features on and off as needed, and access greater information about an area or feature at any moment. It's also possible to collapse elements to utilize a cleaner, broader visual interface. Overall, Electronic Navigational Charts make for much easier and more efficient navigation.

Raster Charts

While ENC's fully integrate the computer features of ECDIS, Raster ECDIS charts are much more simple. The chart's maker simply scans the paper chart so that it's possible to store them electronically. When you use a Raster chart, you aren't going to have any additional functionality or features as compared to paper charts.

In essence, it functions similarly to loading and observing an image on your computer or phone. All text and chart data is constantly visible, and zooming in or out will affect every part of the chart equally. Additionally, rotating the chart will rotate the text as well as the image. Sometimes, it's impossible to procure ENCs for the full length of a voyage, which is when you'll need to use Raster charts and/or paper charts to augment them.

The Advantages of ECDIS

While ECDIS isn't perfect, it has many advantages over traditional paper charts.

Real-Time Information Processing

While a human has many advantages over a computer, a human cannot work as tirelessly and thoroughly as a computer. As a result, one of the key benefits of ECDIS is that they're constantly processing and displaying data in real-time. So long as the hardware and software are working and the end-user has provided the correct inputs, the accuracy and output of an ECDIS are always correct. This level of precision along every step of a journey produces several tangible benefits with major ramifications for the shipping industry.

ECDIS Enhances Safety

When a ship runs aground and needs repairs, the losses can seem incalculable. In addition to the costs of repairs, the time spent inoperational represents a dramatic loss in revenue. In the worst-case scenario, the human consequences and potential for injury and fatality are unbearable. By providing accurate, real-time data on the voyage, electronic navigation systems go a long way in protecting people and profit.

Maximize Profit

Traditional navigation needed to maintain a certain margin of error to accommodate the lower level of precision that was possible. An excessively large margin for error represents many forms of lost profit, such as:

  • Taking considerably fewer containers than was necessary to guarantee a safe voyage.
  • Traversing a substantially longer route than necessary.
  • Scheduling difficulties related to an inaccurate ETA.

A ship that uses an ECDIS can calculate these and other factors much more precisely and constantly update the data available. As a result, electronic navigation doesn't merely reduce the risk of losses, but also increases the possibility to improve profits.

Increased Ease and Efficiency of Operation

Manual course correction, checking for hazards, and related aspects of navigation are poorly suited for human workers because they require constant vigilance. When navigators relied on manual charts and tools, they consumed much of their time with mentally exhausting work that required incredible attention to detail. Simply doing their work required a great deal of effort to organize and find the information, only after which they could act on it.

While modern navigators still require these skills, the prevalence of ECDIS systems takes tremendous burdens off of them. Digital navigation aids automatically compile the information where it's simple and easy to find. Additionally, the busywork of chart correction is entirely eliminated as well. Direct interfacing with AIS, Echo Sounding, ARPA and other tools also saves time and increases information clarity. Now that sailors are free of the work that they had to perform with a pen, they can dedicate more time and energy to the work they perform with their brains.

Navigators also have access to more information in greater detail than ever before. When your ECDIS is using electronic navigational charts, you can highlight features to gain much greater insight. Even on simple Raster charts, the zoom and rotate functions allow for greater clarity and ease of use.

Disadvantages of Electronic Navigation

Only as Reliable as the Data

When a new technical solution is correct 99.99 percent of the time, it's easy to become overly comfortable. However, any machine can fail and human error can also cause misreading. In 2020, the ferry Seatruck Performance ran aground and went inoperational for 3 weeks. The reason was that they simply failed to input squat when using the ECDIS to chart their voyage. While electronic navigation is incredible, this sort of complacency can become fatal.

Fosters Overdependent Crews

It's important that crews don't think that the extra work the ECDIS performs translates into time off duty. Indeed, using electronic navigation creates several new forms of work unique to operating the devices. Not only is it important to make sure that the system itself is operating properly, it's important to have fail-safe solutions to provide redundancy. This might be a second system, or it could be paper charts that the ship may use to complete the voyage.

Update Requirements

While updating ECDIS software is remarkably easy, especially compared to replacing paper charts, it's also important to upgrade hardware. It's easy to avoid a new expense on the grounds that the existing system works well enough. However, as the capability of electronic navigational charts grows, their technical requirements grow as well. Using outdated hardware will cause a drop in efficiency and may eventually pose a risk to the ability of a ship to complete its voyage.

Updating Your ECDIS

There are several ways to update the software and electronic charts on your ECDIS:

  • Using physical media such as DVDs.
  • Download from the internet. (Register for a free trial to our e-Navigation Software SPICA to order and download ENCs)
  • A SATCOM attachment you receive via email.

It's also possible to receive updates via SATCOM broadcast message if you have hardware that enables this process.

ECDIS Carriage Requirements

The international bodies that govern oceanic travel mandate ECDIS charts on certain vessels. Older ships may be able to receive exemptions, but modern vessels that launched after a certain date must carry one.

The following vessels cannot legally undertake an international voyage unless they're using an ECDIS:

  • Passenger ships over 500 GT that completed construction after 30 June 2012.
  • Tankers over 3,000 GT that completed construction after 30 June 2012.
  • Cargo ships between 3000 and 10,000 GT that completed construction after 30 June 2014.
  • Cargo ships over 1,000 GT that completed construction after 30 June 2013.
  • Passenger ships over 500 GT that completed construction by 1 July 2012 and had their first survey after 30 June 2014.
  • Tankers over 3000 GT that completed construction before 1 July 2012 and had their first survey after 30 June 2015.
  • Cargo ships between 10,000 and 20,000 GT that completed construction before 1 July 2013 and had their first survey after 30 June 2018.
  • Cargo ships between 20,000 and 50,000 GT that completed construction before 1 July 2013 and had their first survey after 30 June 2017.
  • Cargo ships over 50,000 GT that completed construction before 1 July 2013 and had their first survey after 30 June 2016.

IMO Standards for ECDIS Performance

The IMO maintains that the main role of ECDIS is to improve navigational safety. To this end, it maintains the following performance standards for manufacturers and end users:

  1. A system must have adequate backup arrangements and up-to-date charts to comply with Regulation V/20 of the 1974 SOLAS Convention.
  2. Shipborne radio rules relating to IMO Resolution A.694 apply to electronic chart display and information systems.
  3. A system must display all chart information that government-authorized hydrographic offices deem necessary for safe and efficient navigation.
  4. Straightforward and reliable software updates are a necessity.
  5. An ECDIS should be able to continuously plot the ships position and execute all route planning, monitoring and positioning that paper charts perform.
  6. Electronic navigation charts and the system utilizing them should have the same visual availability as paper charts.
  7. An ECDIS should include alarms and/or indicators for hazards, malfunction and other relevant information.

ECDIS Training and Procurement

The human element has always played a critical role in a successful voyage. To operate an ECDIS, you'll need to seek out an institution that provides the relevant course. Deck Cadets are typically eligible and will learn how to use the ECDIS over an in-depth 5 day course.

If you're looking for an up-to-date model, SEALL-brand ECDIS is an excellent choice. You can learn more about our SEALL ECDIS and electronic navigation software SPICA by following our blog.