14 Jan 1914. Wednesday.
Frank carried on with the controls today.
First (553) is the rear bearing for the rock shaft, and this was unchanged on the C Scout. You can see that it has bushes at front and back, and this means that it has to be very carefully aligned with the front bearing, or the rock shaft will be stiff in operation. Unfortunately the two bearings are mounted on different parts of the fuselage which, being wood and wire, tends to move a minute amount. This makes it almost impossible to keep the rock shaft as free as we would like. There doesn’t seem to be anything to be done about it, but it would have been better if he’d used ball bearings (which were available at that time) and would have absorbed small amounts of misalignment without stiffening up.
554 shows the rock shaft arrangement, with the elevator cable pulley clearly shown. In front of it (just below it in the sketch) is the lever for working the ailerons. Can you see that it’s called the ‘warping lever’? At this time, opinion was divided between wing warping and ailerons (the Sopwith Tabloid, which was another high speed Scout which had flown a month or so earlier, used wing warping). And although the Bristol Scout was designed from the outset with ailerons, the term ‘warping lever’ has been retained.
555 is the tiller bar bracket, and here again there is an interesting mix of terminology. The terms ‘tiller’ and ‘rudder’ are clearly derived from sailing, and indeed they do exactly the same job. The term ‘rudder’ has stayed in use from then until now, but ‘tiller’ hasn’t. A year later it was called the ‘foot lever’, and when horizontally-hinged pedals became the norm, they were called ‘rudder pedals’.
556 and 557 are the woodwork for the controls.