RCU Forums - View Single Post - What happens if I raise engine on air frame?
Old 01-13-2018, 01:39 PM
  #9  
da Rock
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It was designed for 12" prop clearance? There is another option that could work, and certainly has in the past in full scale and on my models. Use a 12" prop. A 3-blade. They have only two drawbacks.

Finding them can be an effort, and a slight decrease in efficiency (that won't be noticeable to most modelers). Almost my whole squadron uses them. I've got a hangar full of 60 and 90 size aerobatic and warbird models. The aerobatic ones are propped with them because the dia/pitch 3's that are available give me better thrust. The vertical performance is stronger with less loss of speed. Those aerobatic models don't need to be propped for speed anyway. The warbirds on the other hand can be pitched for speed. My bigger Corsair has been clocked at 118 on radar. It was a bit of a surprise since the prop wasn't chosen for flat out speed. But it got it. It's also partly from running it rich and the power from the OS95.

I've got a couple of electrics (warbirds) with 3s on them. I actually picked the motor to match the prop/model combination for one of them. It's got very good acceleration. It's a hoss.

Efficiency ever give a problem? Never noticed. In fact, I've been waiting for a very long time to meet someone who has actually measured it's effect in models.