Yachting in the Shipping Lanes

by Nancy Knudsen on 1 Dec 2006 Well, Hi old chap, welcome to the party. There were ten of us here, all ships together(well maybe 9.1, if you consider this yacht's size); now that you’ve arrived there are eleven of us.

There’s quite a lot of chatter going on at this party – maybe you can join in. Often I think some of the party is quite drunk. Or maybe it’s the language. Many don’t speak much English. Yes it’s quite a strange party, with people arriving and leaving all the time. Any way they seem to have the greatest trouble getting around without bumping into each other.


Japanese, Pakistani, Russian, American, French accents, we hear snatches of them all:
'Port to Port'
'Which do you prefer?'
'Starboard to starboard'
'I am not getting a signal from you, is your receiver turned on?'
'Please alter your course to starboard'
'You must alter course, we cannot'
'Please answer – isn’t anyone awake there?'
'You advised you would alter course but you haven’t moved'
'Red to Red' (this last maybe to cope with language difficulties)

Of course I guess it’s quite a darkly lit party, romantic really. For myself, all I care about is that they don’t bump into me. Sometimes I think they are aiming at me. In fact a couple over the last few hours have made a beeline for us.

There’s nothing scarier than seeing the symmetrical shape of a huge bow headed directly for you when you’re on a small yacht. Suddenly I find gybing the boat with a main and two headsails very easy single-handed! ‘Well done!’ I congratulate myself afterwards, ‘I didn’t know you could do that!’ Marvellous what a little adrenalin can do…..

Since we arrived in the Mediterranean, in June 2004, the scene for ships at sea has changed radically with the introduction of the AIS Receiver. Once ships could identify another ship only by calling to the radar position of the ship they wanted to contact.

Now all commercial ships (here in the Med anyway) have AIS Receivers, and they can identify and call other ships by name.

This has increased the communication greatly, and we also find that ships will respond to our call where previously we thought a great many of them simply didn’t listen to Channel 16. Maybe it also allows ships more flexibility about how close they can come to another vessel, knowing that they can communicate easily.

With the danger of collision with a any fast moving ship always on the mind of cruising sailors, this is a brilliant innovation that enables you, not only to see where the ships are, but to identify them as well. With a possible 12 minutes between horizon and collision, on any ocean, anywhere, it is not a small issue.

As Robin Kydd from Oceantalk the Australian distributor for the new Comar AIS system explains 'This technology is certain to give recreational boat owners an added dimension of safety and peace of mind through commercial shipping technology.

AIS transponders are now carried by all vessels over 300 tons. The AIS transponders transmits relevant vessel information: including Position, Speed, Heading, Call sign (MMSI number) Ships Name and Destination via a simple VHF signal.

This information can now be received by the AIS receiver on your own boat for display on the chart plotter screen. ( a system similar to aviation transponders that allow air traffic to be monitored and tracked on an air traffic controller’s screen.)

The AIS data is incredibly useful to any skipper. You can view an unknown vessel’s MMSI number and call sign: (to allow digital selective calls (DSC) to be made to that vessel.) Knowing the intended course and speed of an oncoming ship could assist you in plotting an alternate course. Keeping an eye on precisely how many ships are in the area, whether they are leaving port or entering. Even to record the Ships position and name in your log could be useful.

The most important advance in navigation, probably in the last five year. It adds to radar, chart plot, allow skippers to concentrate on the smaller boats that do not have AIS

Comar produce two main models, SLR200 Receiver only, and the CSB200 Transponder (Transmits as well as receives.) The units only require a marine style VHF Antenna. Recreational vessels are not legally enforced to carry either type but would be encouraged to fit the SLR200 Receiver in the very least.

The Comar SLR 200 AIS Receiver decodes and allows display of any AIS data received on Raymarine C and E Series displays. The SLR200 unit retails for less than AUS $1000 and is a worthwhile addition to any navigation system.

The Comar CSB 200 transponder is both a receiver and transmitter of AIS data. It gives recreational boats the ability to transmit their own AIS signal in order to recognize and be recognized by other AIS equipped vessels. The CSB 200 will be available from April 2006 and will retail for under AUS $2500.

Both models are easy to install and integrate with Raymarine C and E Series units (software upgrade for C and E units purchased prior to AIS are available to users free of charge via the internet.) Or see your dealer.

Introduced primarily as a vessel safety measure, all vessels over 300 tonnes will be required to fit an AIS transponder by the end of 2007. The safety benefits of AIS data means that many more, non-legislative vessels, are fitting both AIS receivers.

The introduction of affordable AIS receivers, such as the SLR-200 from Comar, enables users to see at a glance a visual display and detailed data about vessels in the area. This is especially useful at night, in fog, or in busy shipping lanes. The speed and accuracy of AIS information is paramount, with information updated every three seconds to six minutes, depending on the category of information, the speed and the rate of turn of the vessel.

The SLR-200 will receive and display the name of the vessel, call sign, type of vessel, destination, speed, course, heading, rate of turn, position, navigation status, vessel dimensions and MMSI number. With all this data, the user can ascertain and monitor vessel movements in the area, plot the progress, changes in heading and speed of nearby vessels, and, if required, call up the vessel.

Designed for use in the hostile marine environment, the SLR-200 is a robust, dual channel AIS receiver, incorporating a synthesised VHF receiver unit in its compact casing. Measuring just 140mm by 120mm by 50mm, it comes complete with trunnion mount, power cable, PC serial cable, NMEA cable and a combined installation/instruction manual.

The SLR-200 is quick and easy to install, requiring a 12/24vDC power source. It is connected to the PC via the serial port and to an external VHF aerial. For ports and harbour authorities, the SLR-200 is an affordable alternative to a high cost full Class ‘A’ unit, enabling them to monitor traffic within the VHF range, track vessels in the areas, and check on the legality of transit, and compliance with speed regulations

The data available from the SLR-200 provides an immediate, visual insight into the status and movements of other vessels in VHF range. AIS capability is now included as a standard feature on the majority of PC navigation software. Integrating AIS data onto the vessel’s electronic chart display instantly improves the safety levels on board, with the quick access to a MMSI (Marine Mobile Service Identity) can often help avoid a potential collision.

Robin Kydd Managing Director of Ocean Talk: 'I recently brought a boat down from Phuket to Singapore, fitting with the Comar SLR200. With heavy shipping traffic, it really simplified the navigators task. Knowing what the commercial traffic was doing, with speed and bearing, we could easily see what boats were of no concern and that let us worry about other smaller ships. This is ce