In inshore waters, it will simply replace conventional radios, but satellite transmitters will be required farther offshore. GMDSS "will send out a digital signal, including the vessel's ID number and its position, and from that everything else can flow", says Bill Speirs, coastguard deputy district controller. Once the coastguard has the ID, it can call up the name and type of the vessel and the number of life-saving appliances on board, and judge what response is needed.
"The great thing about it is if it's a serious situation, where the vessel can get out only one signal, we can still react," Speirs says. "Whereas you had to send quite a long message previously, now you only need the one, although if they have time, we can get back to them by voice."
The nature of the emergency can also be included - so rescuers will know whether they are sinking, are on fire or have lost engine power.
GMDSS is now mandatory on commercial vessels larger than 300 tons (such as a small coaster), passenger ships and fishing boats, and is recommended for all other craft, especially anyone heading far offshore. Until 2005 the coastguard will still keep watch on Channel 16, the standard distress and calling channel, but "I would suggest to anyone buying a new marine radio that it's time to buy one that is GMDSS-compatible," Speirs says.
As with GMDSS, GPS has become central to navigation. Now even the smallest boats can have a low-cost satellite navigation system that fits in a pocket, using Windows CE software launched by Chartwork at last week's London Boat Show. The only drawback of the pounds 149 Pocket WinChart package is that the hand-held computers it works on have such small screens, but the colour image on the recommended Hewlett-Packard machine is clear enough to you to spot where you are, and it can be set to keep your position in the centre of the screen so that it scrolls as you sail.
Like all navigation packages, it needs sea area charts to plot position, but they are now available on PC cards, which plug into the hand-held computer. They cost pounds 115 for a standard-size chart covering a day-sailing area, and pounds 200 for a larger chart (eg for south-west England and the Brittany coast). The only problem is that the PC cards go on draining the batteries even when the computer is switched off, so must be removed. It can connect to any hand-held GPS receiver (now costing less than pounds 100) and also to an autopilot system, for hands-free sailing at less than pounds 1,000.
Burmarc, which sells the system, also showed the world's smallest stabilised satellite TV antenna, which remains locked to its signal in even rough seas (where the boat pitches or rolls by plus or minus 25 degrees in eight seconds). As Andrew Bush, its director of marine sales, says: "If you were sitting downstairs and the boat was pitching and rolling that much you wouldn't want to be watching TV anyway." At pounds 4,000, the KVH TrackVision 45, is about a third of the price of previous seagoing satellite TV systems.
For wealthy yacht-owners, even the dazzling choice of colours offered by the latest iMac isn't enough, so TT Designs Marine Computing sells computer keyboards, mice and monitors carved from wood - mahogany, teak, burr walnut, whatever the customer wants - or even Corian for a marble or granite effect. For the keyboard, all the keys are individually laser- cut from a single piece of solid wood so that the grain runs along continuously.
A mouse costs about pounds 100, a keyboard pounds 350 and an LCD display about pounds 4,500, but, according to TT Designs' senior partner, Tim Thornton, buyers aren't worried about the price. One European yacht owner has asked for a desk incorporating a PC with a cordless ebony mouse, a fax and a shredder, with a concealed LCD monitor that rises and swivels into position at a touch of a button; and in order that his son can surf the Internet from a separate games room, the company is installing an ISDN satellite link (for $10 per minute in connection costs).
PCs are now used to control even the largest ships, which means that they can also be used for training, bringing the cost of a ship simulator down from more than pounds 1m to as little as pounds 1,000. Part of the appeal of PC-based training is that it is easy to build up from a single PC, which may be running a communications package (including GMDSS), to something that looks like the bridge of a high-speed ferry, says Mike Robins, managing director of Transas, producer of a wide range of shipping software, including radar, engine-room control packages and specialist fishing modules. "On just one PC you can run a multitude of different functions, linked to create the most complex training arrangement you could ever have," he points out. "You can even have your bridge linked to another [virtual] ship, which might be across the world.
"Traditionally, only the cream of training institutes could afford a simulator," he says. But even the poorest countries, where most commercial crews now come from, can afford up-to-date training, while shipping companies can build virtual bridges identical to those on their seagoing vessels," Robins explains.
"You can make it as realistic as you like - from an all-screen affair controlled by a joystick, as used on high-speed craft, to more traditional analogue instruments, using exactly the same software as drives the real ships. All that's added is a simulated visualisation, as seen from the bridge."