Around 1957, we Beaver Falls fliers (Grey Hayes, Bill Moran, Eddie Staniek, sometimes Bernie Luger, and yours truly) graduated to big models with big engines. This meant a Fox .35 and a Sterling Ringmaster or F51, a PDQ Circus King, a J. Roberts Sabre, or something of similar ilk. The common denominator was that the planes were all stuntable (would fly upside down and do inside and outside loops) and were all profile models.
We all had mastered straight and level flight, wingovers, and inside loops. We had been able to do the wingovers on 15 foot long lines in the intersection at 14th street and 2nd avenue in front of my house. Serious stunting though, required longer lines and a big 40" wingspan model; thus the big profile models and the Fox .35s. These would be flown on 60 foot lines down at Moultrup's field (the local little league baseball park).
When a Fox .35 is mounted on a profile model, the exhaust points down at the landing gear. The needle valve is normally positioned up at the sky; to put it on the exhaust side produces badly burned fingers as your hand must be under the exhaust to adjust it.
During normal flying this position is no problem as one normally lands on the wheels. While learning to fly upside down and do outside loops however, we very often would land (crash) upside down and this wipes out the top mounted needle valve. Without a needle valve, the Fox .35 will not run.
In 1989 this probably could not be considered a problem. I don't think most RCers of today have ever broken a needle valve. If they have, the whole plane was probably trashed and they didn't even notice the needle valve was broken.
In 1957, especially in June when the summer vacation had hardly started, a broken Fox .35 needle valve was an immense problem. We only had one hobby shop, McCue's, or Mac's as we called it. Mac just didn't stock handfulls of Fox needle valves. He had no way of knowing that 3 or 4 of us would all attempt inverted flight on the same afternoon and each require a new needle valve the next day.
We thus learned to share needle valves. While we shared we of course tried to invent alternate solutions. One of the Perfect mounting bolts fit the spraybar, but we never seemed to be able to get it filed just right to provide smooth adjustment. A handy hint of the day (Fixit Wright's??) said to file a weak spot in the upper part of the needle valve so it would break there instead of down at the spraybar. This kind of worked, but the soldered repair had a way of disappearing in flight; we 14 year olds weren't NASA solderers. Perfect also made a coil spring needle valve extension, but it tended to wrap up and let go, thus preventing fine adjustment (the proper setting was always or - one click for where you were). You didn't dare let it stick straight up, it would vibrate right into the prop.
One way or another, we all did learn to fly upside down and do outside loops. Those of us that stuck with it built full fuselage models and didn't have to worry as often about breaking needle valves.
Sometimes now when I think I have a problem, I think back to when it was June and there wasn't a Fox .35 needle valve in Beaver Falls and then I realize I don't really have a problem after all.
Bill Mohrbacher