.. I was volunteered (being the Junior Tech on the flight) to carry out an air test on a Whirlwind 10 after a major rebuild consisting of engine, gearbox, blades and a shed load of other items sent to us from Leconfield (that's the time when we were given the Northern spare). She had been dumped on the beach West of Lossie after an overspeed (if I remember correctly) and couldn't be flown down South for repair. After a month or so of work by the groundcrew, we were ready for the first flight.
For some reason there seemed to be a bit of a problem getting the aircrew (or groundcrew for that matter) to accompany the pilot on his little soirée. The words "too bloody high" and "dinghy's don't make good parachutes", seem to remain in my mind to this day!. Anyway, duly sitting in the co-pilot/nav's seat with a stopwatch and a small piece of paper and a lot of ignorance, we took off, climbing vertically over the airfield to a height of ten thousand(?)feet. God, it was a long way up in one of those things. It took what seemed an age to get up to height and when we got there, neither of us liked the Jaguars and Phantoms zapping past us at four hundred+ knots whilst we just sat there waiting for this bloody rotary wing to hit the magic height.
Anyway, after a few minutes of this, Castle and the pilot (can't remember his name) were both of a mind that this was not a sane place to be and that if it got up here at all the rate of climb must be bloody marvelous and therefore there was absolutely no reason to stay up here or repeat the test. If my memory serves me well after 28 years, I finished writing the rate of climb figures up on the descent! Oh, the kite was fine, and went on to do quite a few more hours with us before going to HQ flight. Says something for first line maintenance.