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It seems a lot easier to build a plane for theevent than to find a motor to fit the plane.
I can see that later SuperTigres have more power than earleir ones.
An Enya???
Is an OS Max an OS Max whether it’s a mkI, II, III or even later? Seems these motors didn’t change too much in my recollection. I don’t think a modern one is that much different but I’m not an engine junkie.
I think there’s little hope for the event unless motors are available.
You have hit the nail on the head! 1960 and earlier is no problem. O.S. MAX III .15’s are still plentiful and (relatively) cheap and can be reworked into a very powerful engine. After 1960 Super Tigre and Cox raised the stakes. Good Cox engines command over $100 and the better Tigres do too. Later eras are even worse. Finding a pipe with a header which will fit your tigre is difficult, and the engine must be modified to take advantage of the pipe. For the ’70’s you need a good Rossi or Cox Conquest and those are quite rare and expensive. We need somehow something like a registry of people with surplus motors to maximise the number of participants.
The pre 1960 section of Vintage seems the way to go. As in the previous post, O.S. .15’s are readily available even new in the box on Ebay. Doug Galbreath has been modifying them and seems to have it down. The airplanes are simple all balsa affairs with plenty of designs available: Lindys, Amazoom, Jays Bird, Crescendo, Dream Weaver, Pendleton Fault, even a Kiwi, Zeek or Ramrod and on and on. The Ziac books are full of them. Many of these planes qualify for A nostalgia too. Minimum weight is a mere 17 1/2 ounces if you can build them that light. The real kick is the flying, any fuel, 20 second engine run, when was the last time you did that ? Try beating that with a much shorter run and a much heavier airplane. Thermals, Glenn
No one can convince me that for NosFaiPower as written that anything could beat a JaysBird with an OS15 and a 20 second engine run. My 18oz JaysBird with a worn-out Olympic will knock out 2 minutes on 9 secs all day long. The OS would give me 3-4k more rpm and the plane could be lighter.
The 20 sec run is a bit of a mistake, and I emailed Walt about it some time ago;
1st generation FAI models had 20 sec run/ROG/5 minute maxes (3 flights)
2nd generation models had 15 sec run/ROG/3 minute maxes (5 flights), but were otherwise the same aeroplanes.Only when the loading rose to 300 gm/cc did the ROG requirement disappear, so (in my view) if we are holding contests for these models without ROG, 1st and 2nd generation models should really only have a 12 or 13 sec run. That would (should) shift the ‘advantage’ to the 3rd gen. models – 300gms/cc, 15 secs run (hand launch), nitro allowed.
Walt has published (on SEN, I think) that OS Max III engines are OK in lieu of Max I or II, and with Nelson plugs and a few other mods they can be quite the engine.
I’m not a collector by any means, but I have a few surplus to requirements if anyone would care to drop me a pm. It is true that some are a bit rare and pricey – Olivers and ETA 15s particularly – but the repros help out, and genuine Olivers are becoming available again for those that like diesels.
John
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