It is not usual to clock dive passes way in excess of prop pitch speed. For example I had a plane that did a very consistant 152-155 level but out of a big dive I saw over 170.
z06kal.. We are looking at the same numbers but stating the conclusions differently. Earlier I said " As a rule, you will NOT go faster than the prop." What I meant by this is that folks should begin with the calculated speed before posting they are doing _____ mph. It will save folks from posting they are doing 200 with a 10x6.
While you would say "It is not usual to clock dive passes way in excess of prop pitch speed", I would say "you will rarely see dive passes more than 10% of the prop pitch speed". Notice 10% above 155
is 170 so we are numerically saying the same thing but putting it differently.
Soo... a 10x8 at 15,500 rpm static unloads to, say, 18,000k (that is being
very generous) and on the pipe, plus 10% for the dive is 149 MPH. 149 MPH corrected for 3,000 feet is 158 MPH (
http://www.csgnetwork.com/tasinfocalc.html ). Add a 10 knot tail wind and you get 169mph... I guess it's possible.
There are no brakes that come on when a plane exceeds prop pitch speed just some extra drag.
Agreed... but... the prop is increasingly acting as a source of drag (not thrust) as it exceeds it's theoretical top speed. At its theoretical pitch speed, the airplane only "sees" the airframe drag and varying degrees of prop drag (not thrust). That is why it is so difficult to exceed the prop speed... At that speed, there is only drag and gravity.
I'm surprised the Bushnell gun picked him up at all as those guns are generally horrible at clocking small objects at high speed.
I use this gun and highly recommend it.
http://www.stalkerradar.com/sport_im...rdcase-big.jpg
I think we are generally in agreement and please understand, I gain nothing by proving or disproving Hectors claim. I got into this discusion only to suggest that a fairly draggy plane like the Patriot with a fairly low rpm engine like the Rossi, turning a sport APC 10x8 is going to be very hard pressed to go particullary fast.
I should have added much sooner that it is a VERY good looking plane. I got so involved in speed discussions that I forgot to mention it's a very nice model.
Bill