Not every prediction from past volumes of The Motor Ship proves to be accurate: however, the lead article from the February 1966 issue was pretty much spot on.

Container shipping, it said, is going to effect the most sweeping and far reaching changes ever experienced in the cargo liner trades. Although some US and Scandinavian operators had been practising containerised trade for a while, it was only 50 years ago that containerisation was promising to become truly international, and to encompass road and rail traffic as well as ship cargoes. A number of shipping groups, notably in Britain, were forming consortia to promote container traffic across the board. Our predecessors saw a forthcoming revolution not only in the way ports operated, but in shipbuilding and naval architecture – the new trades demanding large, specialised ships, capable of appreciably higher speeds (27-28 knots), and capable of carrying containers for perishable, liquid and other specialised cargoes.

However, it was recent deliveries in the tanker and bulk carrier sectors that were the main focus of the issue. The trend in 1965 had been for larger ships, with 62 new tankers of 100,000 dwt or more on order or in service. One of these – about to begin building at the IHI yard in Japan – was of the unprecedented capacity of 205,000 dwt. The Idemitsu Maru would be capable of carrying 2,000,000m3 of crude at 16.5 knots, powered by a 33,000 hp main engine.

The industry was still undecided on how to achieve these higher powers demanded by the latest large tankers and the forthcoming generation of fast container ships. Single or multiple two-strokes, or new, larger, medium speed multi-engine installations all seemed to offer benefits. Technical managers from various companies contributed to the debate. Fiat of Turin favoured two strokes with increased cylinder dimensions and higher pressures, on grounds of effciency and simplicity. The case for highly rated medium speed power was put by Mirrlees, which cited its K Major as offering low fuel and lube consumption, with compact dimensions and light weight, while Sulzer, with a foot in both camps, was able to provide a more objective assessment.

Two multi-engine installations based on medium speed engines – either two 18-cylinder 40cm bore units or four of 16 cylinders and 30cm bore – were compared to a single 9-cylinder 90cm bore two-stroke, all offering a similar power output. The medium speed options offered benefits which favoured them for specific applications, such as ferries, where the engine room height is important for optimum low-level vehicle deck configurations. Other potential benefits of the multi-engine plant included flexibility, redundancy and maintenance – offering the possibility to exchange a complete engine. The conclusion was, though, that for general ship propulsion, the single large two-stroke was best, principally because of its comparative simplicity – not just fewer cylinders and engine components, but no need for complex reduction gearboxes – and better tolerance of low-quality residual fuels.

Among the ships described in February 1966 was a new Norwegian gas tanker, designed to carry 11,000m3 of LPG or ammonia. The ship, Havgas, came from the Moss yard in Norway, which would later become famous for LNG containment systems. It was the largest of its type in the Norwegian fleet, and came from a range of standard gas carrier designs with capacity of 900m3 to 18,500m3. It was, naturally, the gas system which provided the main interest, with rectangular refrigerated insulated tanks made of special carbon steel resting on hardwood bearers to allow for expansion and contraction. A reliquefaction plant was installed for recovery of boil-off, and the cargo system, like the Kockum-MAN main engine, employed a high level of automation.

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