Advantages of Split Fins?

Are there other advantages to split fin designs besides the obvious CP improvement and aesthetics?

Not that I can think of, unless you are building a scale, semi-scale, or scale-like missile.

That said, some of them are really sexy.

Some of them make a nice whistle as they go up. :wink:

Lol. Pretty much what I figured.

And it might reduce weight.

You get the pleasure of gluing twice as many fins on!

Bat-mite said:

Some of them make a nice whistle as they go up. :wink:

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Which is infinitely better than if they are making a whistle as the come down. :eyepop: :y:

Twice the fillets so you get extra opportunities to develop your filleting skillz.

cavecentral said:

You get the pleasure of gluing twice as many fins on!

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I'm building a 2 stager with split fins (wildman vindicator jr), so I get to attach 12 fins!

They result in getting speeding tickets while still sitting on the pad, which increases insurance rates.

djs said:

I'm building a 2 stager with split fins (wildman vindicator jr), so I get to attach 12 fins!

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Ouch!

If the fins are slightly out of alignment, or if an airfoil effect is introduced, then some destabilizing force vectors can make an otherwise boring and predictable flight go more like a skywriting exercise.

cavecentral said:

You get the pleasure of gluing twice as many fins on!

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o1d_dude said:

Twice the fillets so you get extra opportunities to develop your filleting skillz.

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Like Double Mint gum, twice the pleasure (only without the cute twins), other than the above quoted statements, its all about the cool factor.

Women dig a man that has a rocket with split fins.

Twenty fins and a nosecone.

terryg said:

Twenty fins and a nosecone.

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Hello, my name is Skp and I have split fin envy.:eyepop:

Split fins make you a better human being and you'll get to sit with the cool kids at lunch. I've never heard someone say "Look at this boring split fin rocket."

fyrfytr310 said:

the obvious CP improvement

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cwbullet said:

And it might reduce weight.

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Please explain.

Aerodynamically I doubt there are any "Advantages" unless your rocket is a real missile with active guidance and a warhead.
I prefer models of actual missiles, so for me the "Advantage" is in paying homage to the missiles that do what they do.
I don't care for putting people in rockets or space travel, but I do love to blow $%^& up and what not.
My Split Fin Models will always come back to Earth intact under a chute' or streamer, but I enjoy thinking about them doing their job.
Thusly, I prefer them over other designs.
I don't care about altitude or speed.

I also like the fact that I can line all the fins up so my rockets don't twist on the way up.

Like sparkies I see them as style at the expense of performance.

Buckeye said:

Please explain.

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Less weight aft By reducing win weight will push the CG forward.

K'Tesh said:

Which is infinitely better than if they are making a whistle as the come down. :eyepop: :y:

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That is funny

terryg said:

Twenty fins and a nosecone.

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I don't think I've seen that beauty fly, but I hope to some day! Amazing work, Terry!

-Dave

K'Tesh said:

Which is infinitely better than if they are making a whistle as the come down.

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kcobbva said:

That is funny

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Oh man, I have had two come down ballistic within 20 feet of me and one of them I had no visual on at all. The whistle was absolutely terrifying; at least I can laugh about it now.

watermelonman said:

Oh man, I have had two come down ballistic within 20 feet of me and one of them I had no visual on at all. The whistle was absolutely terrifying; at least I can laugh about it now.

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Back in the 90's I made a scratch build SPEV by combining the fins and nosecone of an ill fated Estes Sizzler (1906) with an Alpha's body tube once (D powered), and a 12 inch (vented) parachute. I had to nearly pack the nosecone entirely with clay to get it to be stable.

I hadn't finished the rocket, and I had two D motors cato on me, so I wasn't taking any chances with a rocket that I cared about. So, I loaded my last D motor into it (I wasn't marking my motors at that time with date/box number, so I didn't know if the motor was safe, or not, but I didn't really understand about Estes replacement policy, and wasn't going to waste the motor by soaking it.

One day I decided to do a launch, so I loaded the suspect motor up into that rocket, and launched it with a friend of mine.

The rocket leaped off the pad, and was well on its way to having a beautiful flight when it suddenly exploded about 15-20 feet off the ground. The remains floated down on us like confetti. Well after the last piece of rocket landed, we started looking at the remains when we suddenly heard a whistle, and a thump. We spun around, and found the parachute fused into a wad lying on the ground behind us only about 20 feet away. I went to pick it up, when I realized that it was attached to the ground. Some gentle pulling, and I was able to extract the nosecone from the soft, wet soil of our football field. It was completely buried to a depth of about 3 inches IIRC. I'm so glad that we didn't get hit by it, I think it would have been painful at best, lethal at worst. I still have parts of that rocket, but no intention of trying to rebuild it.