GPS Tracking of Boats: An Overview of Current Practices and Alternatives

Boats come equipped with various navigation tools, but the use of GPS tracking devices is not automatic. While most modern boats do have GPS receivers, their primary function is not to transmit information. Instead, these receivers are networked with Automated Identification Systems (AIS) transceivers. This article delves into the current practices of GPS and AIS tracking in maritime navigation.

GPS Receivers vs. AIS Transceivers

GPS receivers in boats are designed to identify location, but they do not typically broadcast information. However, these receivers are frequently connected to AIS transceivers, which are capable of transmitting crucial data. AIS transceivers send and receive position, vessel identifiers, and vector information using VHF (Very High Frequency) radio waves. This information is then shared with other vessels in the vicinity and published on the ship’s network, such as NMEA2000, for use by onboard devices like chart plotters.

Transceivers also play a crucial role in extending the range of VHF transmissions. As a result, data from vessels miles away can still be received and displayed on nearby boats' screens. The International Maritime Organization (IMO) has made it a legal requirement for vessels larger than a certain size to have AIS systems in most countries. However, many smaller leisure vessels may only have AIS receivers, or in some cases, none at all.

Commercial vs. Leisure Vessels

Commercial ships almost always have AIS transceivers, as it is a legal requirement in most jurisdictions. This system significantly aids in navigation and safety, particularly in busy shipping lanes or congested areas. However, recreational vessels are not mandated to have these systems, and some may choose to forgo them for cost reasons. For individuals navigating smaller craft, a simple magnetic compass or a GPS-equipped smartphone may suffice.

Supplementary Safety Measures

While AIS provides a valuable tool for safety and navigation, its limitations mean that it must be supplemented by other measures. Radar and visual observation continue to play a critical role in maritime navigation. Radar can detect objects obscured by weather conditions or low visibility, while visual observation remains an essential part of maintaining situational awareness.

Online Resources for AIS Data

There are numerous websites and applications that allow real-time viewing and searching of AIS data. These platforms offer a global view of maritime traffic, including vessel types, headings, speeds, and locations. Some platforms even display historical tracks, providing a wealth of information for maritime enthusiasts, navigators, and researchers.

Examples of such resources include:

The MarineTraffic website, which offers a comprehensive global view of maritime traffic. The Shipfinder website, which provides detailed views of the South African coast and surrounding regions. The World of Boating website, which features a range of views, from global to local.

GPS and AIS: Not an All-In-One Solution

While GPS is a powerful tool for identifying location, it is not inherently a tracking device. To track accurately, the GPS coordinates must be transmitted. However, this requires a dedicated transceiver, which can consume significant power. For long-term tracking, additional power sources or onboard satellite networks may be necessary. The Starlink satellite phone network is one such solution, though it comes with a significant cost.

Most private smallcraft do not have installed navigation instruments beyond a simple magnetic compass. Many operators rely on smartphones with built-in GPS receivers for navigation, especially in inland and coastal waters. However, for those who venture far from shore or at night, more advanced navigation equipment is necessary for safety and efficiency.

In conclusion, while GPS and AIS provide valuable tools for maritime navigation and safety, their limitations mean that a mix of technologies and human observation remains essential for comprehensive maritime operations.