£ S D OF OCEAN RECORDS

Hokitika Guardian, 8 November 1924, Page 4

£ S D OF OCEAN RECORDS

THE PRICE OE THAT EXTRA KNOT.

(Engineer in “ Daily Mail.”)

LONDON, September 24

Viee-Ailmiral Sir F. L. Field’s sporting proposal to round olf his nine months’ world cruise with the British Special Squadron by driving the battlecruiser Hood home across the Atlantic in an attempt to set up a new steaming record raises the question of the cost of record-breaking. The Admiralty declined to entertain the idea on the score of expense. The Ilood is the heaviest warship afloat, and is capable of maintaining a maximum speed of Ml knots, or nearly 3o miles an hour. The thrilling sens.', lion of speed in travel is probably bert experienced in driving a 110,000 horsepower ship through a lively head sea ■ but the price of that extra knot icquired “to break all previous records’* has to be considered.

■Whatever the mechanism or fuel used in the development of power for propelling a ship, the power so expended is dissipated mainly in overcoming what is technically known as the ‘s dn friction” of the ship, which in an ocean liner may amount to 00 to 70 per cent, of the total water resistance. The object of shipowners is to cany as much cargo and as many passengers and to earn as large a profit as possible fora given expenditure of capital and fuel. The economic sliced is therefore determined by the class ol vessel. But very high' speeds are unduly extravagant in fuel, the additional cos; of an extra knot being out of all semblance of direct proportion to the lime saved. C2,fiof) A DAY. For instance the normal fuel cost ol running an 18,000-ton coal-lired liner at 20 knots is of the order of C 1,200 per day. At 2-j knots the daily cost would be L‘2,o-70.

The difference in fuel cost in driving the Hood at a moderate speed of. say. 2(1 knots and at her maximum of 31 knots would, be, in normal circumstances, proportionately greater in the same ratio. But with a hull fouled with a profuse growth of barnacles and seaweed, as the Hood’s hull must inevitably be after her nine months’ cruise, the skin friction, and consequently the fuel consumption for a given speed, would also he greatly increased.

In can therefore readily he understood why the gallant Admiral was refused permission to drive his ship in an attempt at record breaking on the ground that such an effort would be a waste of fuel.