ORIGINAL: F-4
Matt,
Noticed you were on line and thought I would ask about the status of potential gassers for pattern. Appears most folks are in hibernation relative to news on the SAP 180. I fly a few contests each year (D5) using an OS 160 in an Impact. Am considering switching to gas in a new airplane. Will this thread continue to be active? Is there another thread on the subject of pattern and gassers? Is there another engine showing promise being discussed elsewhere? Thanks.
John
John,
It depends entirely on what you want to fly and which sequence....
My SAP 180's served well in my pattern planes for almost 3 years, flying the masters schedule. Early on we had a couple issues, namely prop drive woodruff key, and front bearing, which Todd took care of immediately. The changes were incorporated into current engines. The engine is a revver and needs to spool up to be happiest. I ran it with a standard apc 17x12 early on and it was a good set-up but I had to run it a little rich to keep it from sagging. Then at Bob Moulder's urging, I switched to a 16x12 which cranked the rpm quite a bit, and the engine simply sang at the 8800-9000 rpm region. It was very happy and my 10 1/2 pound Temptress flew very well with the small prop
But is it THE answer for Pattern? It probably was 10 years ago when we ran OS140RX's. Since then, many things have changed, key among them a slower much more constant speed presentation. The engine requires throttle management and finnesse and it do a great job. After all, it is a great little sport engine that I adapted for pattern....
Are there engines more suited to Pattern? I've found that the OS33GT has the stump pulling power we are looking for but mine was a lemon with factory defects. I had one heck of a time getting the engine fixed. And now of course in the middle of winter, we can't get any more data.
I absolutely love my DLE55 with a 3 blade prop. It is heavy and not many will be able to get a plane set-up and make weight...
So to answer your question, do we have a good gas solution for Pattern? I think the closest is possibly the SAP at high revs or the 33GT which is still largely unproven. I suppose you could always use the very expensive YS170/175 and electric set-ups, but those are always on back burner and are everpresent options Hope that answers your questions. Sorry but I don't have a direct "YES" or "NO"