These little things are sent to try us.
Stanwell,
I like your theory about apostrophes and the ingenious way you cut off the supply at source on the Orderly Room typewriter. A file can prove useful in all sorts of ways:
The designers of the control runs for our Wright Double Cyclones were unduly anxious about the possibility of a pilot closing the throttle completely while the mixture control (next door in the quadrant) was left leaned-out half-way forward. Accordingly they fitted a little spring loaded one-way catch on the throttle which allowed you to advance it past the mixture control, but if you then tried to retard it, the catch would engage the mixture lever amd draw it back with the throttle. It was a nice idea.
Only snag was that the optimum fuel-saving mixture position was about half-way along the quadrant, which by ill chance was exactly the same spot that you had your throttle when climbing in formation with a full load. As you were constantly jiggling the throttle to keep station, it would keep pulling the mixture back, and you had an extra, unwanted task in having to re-set the mixture every minute or two.
Clearly the catch was more trouble than it was worth; five minutes with a sharp file and it was in the bin. One little nuisance had been abated. A small victory !
Danny.