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Horatio Phillips' Feb 28, 1908 To the Editor of Engineering Sir - ... The accompanying illustrations show the machine I tried last summer. In previous machines I used only one frame of sustainers, but found the longitudinal stability defective. In my last machine I used four frames of sustainers. The general dimensions of the machine can be judged from the propeller, which is 7 ft. in diameter. The photographs do not show the driver very distinctly. The body of the machine consists of a triangular girder with lattice bracing of steel ribbon, the weight is supported by two 28-in. pneumatic tyred wheels, there are two other smaller wheels to keep the machine upright when resting on the ground. The propeller is in front and is driven by an eight-cylinder diagonal air-cooled engine, giving from 20 to 22 brake horse-power at 1200 revolutions per minute. The engine is not a copy of the "Antoinette" because it was made several years ago and has seen long and rough service, it having been in four smashes, caused by running into trees, hedges, ditches, &c; it is now being fitted with its fourth crank-shaft. The propeller, being in front, is always the first thing to come to grief; one blade gets broken off, and the unbalanced weight of the other blade generally cripples the propeller shaft and crank. For the future a universal joint will be placed between them. The sustainers are 1 1/2in. wide and 1/8in. thick, with 2in. spaces between them, the section being that shown [no section was illustrated]. On this occasion I used a very large amount of supporting surface, in order that the machine should not have to run far on rough ground before rising. When the machine was ready for trial, I, with difficulty, obtained permission to use a very uneven grass field. The machine was started in a dead calm, at first the jolting was terrific and as soon as it was fairly off the ground the boundary of the field was nearly reached. The machine is provided with a vertical rudder, but it would have been madness to have attempted to describe a circle in the confined space I had at my disposal. A low post was then fixed in the centre of the field, and the machine tethered to it by steel wires 200 ft. long. On the first attempt to run the machine round the circle, the severe jolting broke the crank-shaft in two places and did considerable damage to the engine. Thus ended the trials for last year. Machines intended to start with a preliminary run on rough ground should be mounted on springs, and a universal joint fitted between the propeller and crank-shafts. Yours faithfully, Horatio
Phillips
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