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  SILICON CHIP www.siliconchip.com.au Publisher & Editor-in-Chief Leo Simpson, B.Bus., FAICD Production Manager Greg Swain, B.Sc. (Hons.) Technical Editor John Clarke, B.E.(Elec.) Technical Staff Ross Tester Jim Rowe, B.A., B.Sc Nicholas Vinen Photography Ross Tester Reader Services Ann Morris Advertising Enquiries Glyn Smith Phone (02) 9939 3295 Mobile 0431 792 293 glyn<at>siliconchip.com.au Regular Contributors Brendan Akhurst Rodney Champness, VK3UG Kevin Poulter Stan Swan Dave Thompson SILICON CHIP is published 12 times a year by Silicon Chip Publications Pty Ltd. ACN 003 205 490. ABN 49 003 205 490. All material is copyright ©. No part of this publication may be reproduced without the written consent of the publisher. Printing: Hannanprint, Noble Park, Victoria. Distribution: Network Distribution Company. Subscription rates: $105.00 per year in Australia. For overseas rates, see our website or the subscriptions page in this issue. Editorial office: Unit 1, 234 Harbord Rd, Brookvale, NSW 2100. Postal address: PO Box 139, Collaroy Beach, NSW 2097. Phone (02) 9939 3295. Fax (02) 9939 2648. E-mail: silicon<at>siliconchip.com.au ISSN 1030-2662 Recommended and maximum price only. 4  Silicon Chip Publisher’s Letter Cruise ships are technical marvels Just recently I took a short break and travelled on the Radiance of the Seas, down the east coast of Australia. This was my third cruise and each time I have come away mightily impressed by the fantastic range and depth of technology employed on these floating cities. The amount of technology in use affects virtually every ship-board operation and most of it is largely invisible to the passengers (because large areas of the ship are simply off-limits to passengers). And of course, even where it is clearly on view, the technology and its complexity is seldom understood or even noted by the vast majority of the passengers. The Radiance of the Seas was particularly interesting for me because it uses two 25MW gas turbines for propulsion. Most large cruise ships use two huge diesel engines. The gas turbines drive alternators which then power two 20MW electric pod drives at the stern. These can be turned to face in any direction so they can double as stern thrusters as well as being able to drive the ship in forward and reverse. But the gas turbines are used in a closed cycle, much like gas-fired closed cycle power stations which have the gas turbines drive alternators directly and then their exhaust heat drives a boiler to generate steam and drive another alternator. In the case of the Radiance, the exhaust heat drives a 7.8MW steam turbine to generate electricity. For the passengers, the most apparent benefits of the gas turbines were the absence of vibration which is always present in a ship with large diesel engines, and the lack of diesel fumes. Apart from propulsion, lighting and air-conditioning, the ship also has evaporators and reverse-osmosis desalination to produce the huge quantities of fresh water needed every day. As well, all sewage and waste water must be processed to a high standard before being discharged overboard and waste food is macerated before it too is discharged overboard. Other heavy electrical loads are the eleven elevators throughout the ship and of course, the ship’s kitchens and laundry which must cater for up to 3300 passengers and crew. Apart from that, there are the complex systems which provide for public address, surveillance and fire safety all over the vessel, video entertainment, WiFi (in every cabin but you have to pay to use it!), all the systems in the casino, all the entertainment systems in the bars, dining rooms, gymnasium and so on. I should not forget the stabilisers which are a standard feature of every cruise ship. On the Radiance these are two 7-metre wings which protrude below the water line and which swivel constantly to “fly” the hull through the water as it powers along. Without them, cruising as we know it would be a far less comfortable exercise. One piece of technology which was clearly on view and appreciated by those passengers who used it was employed in the pool tables which are gyroscopically stabilised. It works extremely well even though those who played pool found it quite a disconcerting experience as the tables moved markedly, to compensate for movement of the ship. So what was the most impressive feature? Clearly, this was on show each time the ship slowly berthed when it came into port and when it departed each evening. It was awe-inspiring to watch as the 100,000 tonne vessel silently inched up to the pier, propulsion pods and bow thrusters intermittently operating, all under the control of a joystick and not a tug in sight! But the best moment for me was when the ship was leaving the International Terminal at Sydney’s Circular Quay. As the ship came abreast of the Opera House the fog-horn gave an almighty blast. Now that was a wonderful adrenalin-charged moment! But that is old fashioned technology, isn’t it? Leo Simpson siliconchip.com.au