RCU Forums - View Single Post - What to choose for 2 Stroke Engine, RPM or Thrust??
Old 05-03-2010 | 06:25 PM
  #2  
CGRetired's Avatar
CGRetired
My Feedback: (1)
 
Joined: Sep 2004
Posts: 8,999
Likes: 0
Received 3 Likes on 3 Posts
From: Galloway, NJ
Default RE: What to choose for 2 Stroke Engine, RPM or Thrust??

Thrust is a reaction force described quantitatively by Newton's second and third laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system.
Determine the optimum engine RPM by using different props. Run it that way.

Noise does not equate to power. If you get to high in RPM, you gain nothing but noise and wear and tear on the engine. If the manufacturer states in the engine specs something like "3.2HP at 16,000 RPM", well, it's theorically possible, but not very practical. It's trial and error in selecting the right prop for your plane and you probably will find that it runs best and pulls best at, say, 12000 rpm.


CGr.