|
seanychen -> RE: Saito 82 RPM and Thrust Measurement (2/9/2007 3:40:24 AM)
|
quote:
ORIGINAL: RVM How on earth did you get 10300 RPM from an APC 14x6 with your Saito .82? With 25% Omega I peak my .82 at 9600 (with spinner, but I don't think it makes that much difference) on that prop. I'm at sea-level too. Also, I get 8800 RPM from a Pro Zinger 15x4, which seems to put more load on the engine than the APC 15x4w. I once got the APC 15x4 to peak at 9660, but the best peak I've gotten since is about 9450, and that was on a bench. On the plane it's never been higher than 9200 RPM. Either I've got a really crummy engine or you've got a really good one. quote:
ORIGINAL: seanychen Here it is: Fuel, 30% heli, Wildcat Youngblood Mix Temp: around 80ºF APC 14x6 @ 10300 rpm = 9.5 lb MA K-series 14x6 2nd gen. @ 10600 rpm = 9.25 lb APC 15x4W @ 9700 rpm = 9 lb Pro Zinger 15x4 @ 10300 rpm = 8.75 lb Tachometer: Royal Tachometer Thrust measurement is done by attaching a digital force gauge with an extension bar, hooking to the Sullivan tail gear brass collar on a Funtana 40. All measurements are sustained reading, not the initial peak reading. This confirmed what I found in the air, that APC 15x4W does not pull as well as APC 14x6. If anybody has different thrust finding, please post. Thanks[8D] What 25% fuel are you using? I think I tried it once and didn't really like it. Heli fuel w/ 23% low viscosity lube work great on Saito & YS. If you get APC 15x4 to peak at 9660 on bench, then it's pretty much the same I got on that prop. APC 14x6 is indeed lighter load than APC 15x4W. Pro Zinger 15x4 is narrower than APC 15x4W, and should get a few hundred rpms more than APC 15x4W, but not as high as APC 14x6. Maybe your setup on the plane is causing some variance. There is a quick fix though. Put on an APC 14x4W and rev it high. This engine seems to be more concsistent when it full-throttles above 10k.
|
|
|
|