Details on Wolseley-Siddeley [1908]

The 400-hp British Racer "Wolseley-Siddeley"

The 400-hp British Racer Wolseley-Siddeley
The British Challenger for the Harmsworth Motor-Boat Trophy
Wolseley-Siddeley ~ Daimler III Match Race

A speed of 30.18 knots, or something over 34.75 miles an hour, was the unofficial record attained by the British challenger, Wolseley-Siddeley, on her trial. This, then, is the first performance of the splendid boat which will struggle against the best products of American ingenuity in a little more than three months' time. This also is the fastest time ever made by a gasolene-propelled craft. it is better than the first reports of Panhard-Tellier's time at Monaco last year, which record was afterwards proven incorrect by re-measurement of the course. Wolseley-Siddeley is 39 feet 4 inches long, 6 feet beam, , and her maximum draft at the propeller is 2 feet 8 inches. Within this splendidly constructed hull there is immense power. Her two great, eight-cylinder motors each develop by careful test about 207-hp. at 1,000 r.p.m. A few years ago it would have been considered an impossibility to place 415 horsepower in a hull less than 40 feet long.

One who took part in the trial trip of the Wolseley-Siddeley describes the sensations in the English Motor Boat as follows:

"The port engine was started up, moorings cast off, and the clutches let in; then came a few seconds' clatter as the positive drive took up, and we were away. A sudden leap ahead showed that the starboard engine had started on the drag of its propeller, and Wolseley-Siddeley slipped out of Cowes harbor at a comfortable cruising speed of about 20 knots. After a couple of preliminary runs over the half-mile course, a start was made for Stokes Bay in a flat calm, and I began to think the boat suitable for a picnic party, so slight was the vibration set up by those sweet-running motors. But ting went the engine room telegraph, and only the coaming of the cockpit saved one from lying flat on one's back for the engines had been opened out and the boat flew at a speed that quite eclipsed all previous experiences of the writer. The light feathery bow wave rose, shutting out the view on either side, and fell far astern, while right aft the slight disturbance from the propellers could be seen, but of actual heavy wash there was none. * * * The bow does not lift much, even at top speed, but it does to some extent. Now the stern is invisible in spray, but looking aft it can be seen, and from careful observation i was convinced that the stern was only just touching the surface of the water at full speed. This means that a speed has been reached at which the boat runs on a very mush reduced displacement, a supposition which is in agreement with mr. Saunders' own views, for, as he pointed out, 3 1/2 tons of water displacement at 30 knots would make far more wash than is thrown up by Wolseley-Siddeley. * * *

"Stokes bay was reached in an incredibly short time, and a couple of runs were made over the mile with six aboard, and in spite of one run being slightly spoiled by having a sheer off the correct course, a speed of just 30 knots was registered in the writer's presence. In a later trial a mean speed of well over 30 knots was made (later information states 30.18) and this with the engines running at 920 r.p.m."

Wolseley-Siddeley has been described in earlier issues of MotorBoat, that is, her method of construction, etc. But since she was launched other facts have come to hand that are of additional interest. The hull is of timber throughout, and the planking is built up of three skins of wood, the inner skin of special oak, laid vertically, the second skin of the same oak, laid diagonally, and the outer skin of mahogany, laid horizontally. This outer planking is in one length from stem to stern. The displacement of the boat, in racing trim, is only 71 cwt. and the weight of the engines amounts to 4,200 pounds. The engines were built by the Wolseley Tool & Motor Car Co. Ltd., and there is 5.7-hp. for every cwt. The two engines operate twin screws, and the motors, apart from the obvious design of the crank-chamber for ease of accessibility afloat, do not differ greatly from the standard practice of the Wolseley Co. It is stated that the actual weight of one of the motors in the test bench was 1,670 pounds, which is almost eight pounds per brake horsepower. In the construction of the motors, the high tensile nickel chrome steel manufactured by Vickers' Sons & Maxim, Ltd., was used extensively.

In installation the motors and propeller shafting were set at an inclination of about eleven degrees from the horizontal. The shafts of both motors are supported at the one end of a long stern tube, and between this and the propeller there are two bearings on brackets suspended from the hull. The cylinders of the motors are of close-grained cast-iron, and their formation differs from the ordinary practice in that the water jacket of each pair is separately fitted, and consists of planished copper. The advantage of this method is the possibility of examining the outside of the inner wall of the cylinder after the casting has been made. The copper jackets are screwed to the cylinder castings. The valves are of the ordinary mushroom type and are placed side by side with the usual type od spiral springs. The carburetor is placed high up on the outside in each case, and connects by a pipe across the cylinder-head with the mixing chamber, and with an induction manifold on the inner side. Both high-tension battery and high-tension magneto ignition are provided, and lubrication is effected from oil pumps, two for each motor, mounted on the side of the crank chamber. The propeller shafting base is of Vickers' axle carbon steel of tensile strength of 40 tons per square inch, and is 1 11-16 inches in diameter.

(Transcribed from MotorBoat, April 10, 1908, pp. 47, 48. )

[Thanks to Greg Calkins for help in preparing this page. —LF]

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