Tuesday, 29 January 2013

AIS Marine Equipment and Websites for Sailboats and Cruising Sailors

AIS (Automatic Identification System), like all new systems, was slow on the uptake when it was first introduced not so long ago. But, as is generally the case, a few years down the track, equipment costs come down and the system becomes more affordable and available to the average sailor and in this case the cruising sailor or any sailor who is operating in busy areas with a high density of marine traffic.

In addition to that there are now several websites devoted to publishing online the movements of all vessels in a specific area that are operating (switched on) their AIS systems.

By law, any vessel over 300 tons and all licensed passenger vessels ( no matter what size) are required to have AIS installed and operating when underway.

Here are some of the broader details as outlined on Wikipedia:

'The Automatic Identification System (AIS) is an automatic tracking system used on ships and by vessel traffic services (VTS) for identifying and locating vessels by electronically exchanging data with other nearby ships and AIS Base stations. AIS information supplements marine radar, which continues to be the primary method of collision avoidance for water transport.


Digital Yacht AIT2000 Class B

Information provided by AIS equipment, such as unique identification, position, course, and speed, can be displayed on a screen or an ECDIS. AIS is intended to assist a vessel's watchstanding officers and allow maritime authorities to track and monitor vessel movements. AIS integrates a standardized VHF transceiver with a positioning system such as a LORAN-C or GPS receiver, with other electronic navigation sensors, such as a gyrocompass or rate of turn indicator. Vessels fitted with AIS transceivers and transponders can be tracked by AIS base stations located along coast lines or, when out of range of terrestrial networks, through a growing number of satellites that are fitted with special AIS receivers.

The International Maritime Organization's International Convention for the Safety of Life at Sea requires AIS to be fitted aboard international voyaging ships with gross tonnage (GT) of 300 or more tons, and all passenger ships regardless of size.
iCom MXA5000

It is estimated that more than 40,000 ships currently carry AIS class A equipment. In 2007, the new Class B AIS standard was introduced which enabled a new generation of low-cost AIS transceivers. This has triggered multiple additional national mandates from Singapore, China, Turkey, and North America affecting hundreds of thousands of vessels.

In 2010, the most commercial vessels operating on the EU inland waterways were mandated to fit an inland-waterway-modified and -approved AIS Class A device. The entire EU fishing fleet over 15 meters was given until 2014 to do the same. Additionally, a number of other countries, including China, India, the United States, and Singapore, have started AIS mandate programs which require large numbers of vessels to fit an approved AIS device for safety and national security purposes.'

Class B units:

Simrad text only Class B transponder 
'Vessel-mounted AIS transceiver (transmit and receive) which operates using either carrier-sense time-division multiple-access (CSTDMA)or SOTDMA; there are now 2 separate IMO specifications for Class B. Aimed at lighter commercial and leisure markets. CSTDMA transceivers listen to the slot map immediately prior to transmitting and seek a slot where the 'noise' in the slot is the same or similar to background noise, thereby indicating that the slot is not being used by another AIS device. Class Bs transmit at 2 W and are not required to have an integrated display: Class Bs can be connected to most display systems where the received messages will be displayed in lists or overlayed on charts. Default transmit rate is normally every 30 seconds, but this can be varied according to vessel speed or instructions from base stations. The Class B type standard requires integrated GPS and certain LED indicators. Class B equipment receives all types of AIS messages.'

The interesting point here is that with the introduction of the new Class B, transmitting and receiving, but not requiring a integrated display, has brought the price of such units down as low as $400 by some manufacturers - certainly within the price range or budget of any serious cruiser.

Add to that now are the websites that can be pulled up on your laptop or iPad screen and you can monitor all the ships in your area that have AIS operational.

An excellent example of this is the site www.marinetraffic.com which gives you all the data you could wish for and much more. You can select any area of the globe from their map, zoom in on it and see all the vessels in that segment that have their AIS operational ( a recreational vessel in a marina may have it turned off).

You can look up any vessel worldwide and get their specifications, current whereabouts, course, speed and track them, but more importantly, it shows the vessels in your immediate area, what they are, speed and heading.  

Check out this window of Dover Straits, UK, on their site:

AIS has come a long way in a few short years and now that it is affordable for the average yachtie, cruising or otherwise, the onus is on us to take advantage of this additional safety equipment. 

Digital Yacht Smart Chart 500 AIS
It won't be long before AIS is built into other equipment and in fact Digital Yacht already have their 'Smart Chart 500 AIS' plotter on the market at around USD550 - good value! 

You can read more about navigation and safety whilst on passage in my ebook 'Sailing Adventures in Paradise' downloadable from my website www.sailboat2adventure.com 









  


1 comment:

Capt Jerry Robbins said...

Great post Capt,thanks for the great info!