M104 Patriot Fin Size

[rocketgroupmike]

Hi all, I'm assembling parts for a BT-80 Patriot Missile. (approximately 1/6 scale) My plan is to use an Estes NC-80A nose cone, do you think it is "close enough" to true scale? My main problem is that most kits seem to have larger than true scale fins, so I don't want to copy them. Does anyone know the fin size of the real rocket? (including thickness?) Thanks in advance.

 

[MetMan]

Mike,

Not sure where I got this from. Author block says Jim Ball. Hope this helps a little.

MetMan

 

[MetMan]

Here's a pic I saved of the fins. Again, not sure of the source. If I find the link, I'll shoot it out.

The color scheme is pretty unique. The "war shot" Patriots are unfinished in the launcher so the colors are just from the resins and other materials used in construction.

MetMan

 

[MetMan]

Nose shot...

 

[MetMan]

Found some links:

https://www.asp-rocketry.com/patriotphotos.html

https://www.yellowjacketsystems.com/jimball/scale-data/scale.htm
(scorll down about two thirds for Patriot drawing)

 

[rocketgroupmike]

Thanks, MetMan! The only thing is that drawing shows a fin span of 36 inches, while this link shows 33 inches.

https://www.designation-systems.net/dusrm/m-104.html

Any other comments?

 

[brianc]

Originally posted by rocketgroupmike
Thanks, MetMan! The only thing is that drawing shows a fin span of 36 inches, while this link shows 33 inches.

https://www.designation-systems.net/dusrm/m-104.html

Any other comments?

Standard disclaimer from the D-S pages-

Data given by several sources show slight variations. Figures given below may therefore be inaccurate!

Good luck with your build!

 

[Ryan S.]

For the Patriot I am building right now, I oversized the fins. They are scaled down versions of the actual fins, although they are not the same scale as the body tube. This keeps it looking pretty scale, and also keeps the rocket stable without large amounts of noseweight. The fins on the real thing are tiny, but it has alot in the nose.

https://www.rocketryforum.com/showthread.php?s=&threadid=10979

 

[rocketgroupmike]

Nice work, Ryan. I hope to see that Patriot fly someday... So what dimensions did you use for the fins? I'm still looking for numbers, especially for the thickness.

 

[Ryan S.]

Thanks, you probably will depending on where you fly.

I used a scale of 62.5% for the fins and 50% for the body tube. It isnt EXACTLY scale, but it makes it more stable and it looks kinda scale, moreso than the PML verision at least.

I based it on the drawing from Jim's scale library, it seems pretty accurate.

If you use those scale fins, you are going to need ALOT of noseweight.