In the mid 1960s I was the youngest new arrival in the Defect Investigation Department of a large aircraft component manufacturer in the English Midlands, and was placed in the care of Brian, a pleasant quietly-spoken man, to be shown the ropes. "This'll keep you quiet for a while." he chortled, picking up a device about the size of a large pineapple made of aluminium. It was a Follow-Up Control Valve controlling the nose-wheel steering of the Fokker F27 Friendship whilst on the ground, via a wall-mounted steering wheel. The controls of the F27 are, somewhat unusually, entirely pneumatic rather than hydraulic, and Brian explained that the type was plagued with steering problems while taxying, the pilots unable to steer a straight path, wandering down the taxiways as if they had been on a drunken binge. The problem was causing everyone a lot of grief, and it had been in the department for months. The device had been repeatedly taken apart and every item inspected under a microscope, but it was still a complete mystery causing the company considerable embarrassment.
While he was telling me this, clutching the item in his hands, I could see a roughly figure-of-eight-shaped spring spanning two stout pins on the side of the casing, one of them clutched tightly by the spring, and the other floating around between its two not-quite-parallel legs. As a cyclist and motorcyclist well used to tinkering I took the description to be a classic case of back-lash somewhere in the steering, and immediately suspected this as a likely cause, but it was so obvious I thought I'd better say nothing until I'd had a closer look. If it WAS the problem, surely others must have seen it earlier.
As instructed I took the device down to my gliding friend Jim MacDonald's pneumatics test house and had it set up for a test run. Sure enough, it was way out of limits, and clearly the problem lay in the back-lash of this spring staring us all in the face. Now I, of course, was merely a spectator dressed in a clean suit and tie, so I asked the chap running the test equipment if he could find me a pair of stout pliers, and explained what I intended to do. He nearly exploded. "You can't do that! This is aircraft equipment." After I'd promised to throw away the spring afterwards, he found some pliers, and I bent the spring enough to remove the backlash. (The fact the spring was soft enough to bend was telling us something!) Lo and behold, success, and the subsequent test-run saw the valve pass with flying colours.
I had been gone barely an hour, and my arrival back in the office with an explanation of my discovery did not, to my surprise, earn me universal plaudits. Quite the opposite. In addition to annoying my 'minder', who thought he had got rid of me for a week or two, I had embarrassed just about everyone who had looked at it and failed to spot the simple answer. As a young man from academia, inexperienced in office politics, it hadn't occurred to me that Clever-Clogs are not generally popular.
The next step was to get the drawing out, where it became clear that there was no requirement for the legs of the spring to be parallel when fitted. The only sensible way to do this was to supply the manufacturer with a test fixture for use by their own inspector, enabling him to check their production whilst in progress. Sad to say, Politics reared its ugly head and the Drawing Office refused to acknowledge the omission (loss of Face, again) and fought this change for close on twelve months before it was instigated and the amended drawing and test kit reached the right place - the inspector on the production line of the spring manufacturer. Office Politics had well and truly set me up as a target, and I had to take great care not to repeat the mistake. I have no doubt that I was twice set up and caught out in the three years that I was there as a direct result of the embarrassment felt by others over that F27 valve, but I did have at least another three satisfying successes before a combination of departmental change and National Politics led me to move on.
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