best fin design =advanced=

[jraice]

Seems the long skinny fin, what I thought would give optimal speed and altitude, doesnt, attached is my CF rockets rocksim file but the fins are not final, originally it had 9" long right triangle fins, then I found that the point of the triangle should be a couple inches above the bottom of the fin for more speed, then I tried a stubbier fin and it simmed out even faster. What type is best? The stubbier ones simulate faster but could be more threatened by fin flutter.

 

[Nate]

check out the binder design Sentinel. it's a pretty optimum fin shape for low flutter, low drag, and great for fast speeds.

 

[jraice]

I am thinking a triangular fin, could do a swept fin but that is very easy to break on landing, so basically, is a right triangle, or triangle with a higher point better? it is only a difference of a few 100' and about 50MPH so I will go with a small fin that wont be damaged easily but still sim's pretty high. Also, while we are talking about drag, what size launch lug would simulate 2 standard rail buttons?

 

[Nate]

Originally posted by jraice
I am thinking a triangular fin, could do a swept fin but that is very easy to break on landing, so basically, is a right triangle, or triangle with a higher point better? it is only a difference of a few 100' and about 50MPH so I will go with a small fin that wont be damaged easily but still sim's pretty high. Also, while we are talking about drag, what size launch lug would simulate 2 standard rail buttons?

umm....I just suggested a triangular fin....with a low point....did you look at the rocket I suggested? it's fins are nearly perfect for high altitude and high speed.

 

[jraice]

They have 4 sides, that is not a triangle according to my geometry teacher. I just like the looks of a "real" triangle, and the point a little ahead of the back works well it rocksim, any other triangular designs? I am looking at the sentinel as we speak and it has a semi flat trailing edge and isnt a triangle at all... thanks for the good input though... I actually tried the design in my rocksim file and it didnt work that well compared to a regular triangle.

 

[Nate]

umm...well, you could always modify it to fit your needs. just take off the trailing edge and modify it into a triangle to fit your needs.

Good luck!

 

[jraice]

Then it would be a completly different design, well anyways, guess there really is no answer but play with it for max speed and altitude but make sure it's span isnt huge and make sure its stable... thaks

 

[blackjack2564]

Do a search on the performance competitor 4 .....it has the high speed fins you are looking for also the same on the mega nuke

 

[blackjack2564]

Sorry I ment mega nuke...from loc...there is a picture on their homepage and in the catolog under 5.5 in rockets... www.locprecision.com