ACME Spitfire, sort of

[geof]

I've always wanted to make something like Fliskits A.C.M.E. Spitfire, except crazier. What I really want to know is:

Why does it work? Or more precisely, what makes it not fail? What constraints are there on the "off-kilter craziness", or to what extent can I go wild. For example, I have a ton of old nose cones...maybe I could make a rocket that is all noses. Or, could I even go to G/H motors?

Although I'm not really looking for plans here, I was wondering if this was the right place to ask. Some guidance on the ACME Spitfire idea or just the general principles involved would be great.

Geof

 

[KennB]

The forum has to make showing your location a requirement; I've got to know where to avoid going outside. :y:

No, really, hats off to the experimenters. There are some great ideas out there.

This is just speculation on my part but I've been LCO for lots of ACME Spitfires and am always impressed with their flights. I think the oversized nose cone skirt helps deflect the air stream "around" the jointed body. The fins extend out far enough to pick up the air stream for their famous stability. Both just guesses on my part but that what it looks like to me.

I don't know how Jim does it but he's always coming up with these great designs. And, at a launch, he's always interested in what others have come up with.

I wish you well with your ideas. Just let me know when to break out my reinforced umbrella.

 

[Ted Cochran]

Keep the thrust axis through the center of mass; use large fins, make the drag roughly symmetrical, don't fly too fast.

 

[powderburner]

All the above, and keep the c.g. in front of the c.p.

 

[geof]

All the above, and keep the c.g. in front of the c.p.

So that's been my problem all these years!
:bang:

 

[gdiscenza]

So that's been my problem all these years!
:bang:

Yep, you're probably unstable. :duck:

G.D.

(total disclosure, I am definitely CP forward of CG)

 

[KennB]

All the above, and keep the c.g. in front of the c.p.

Yep, you're probably unstable. :duck:

G.D.

(total disclosure, I am definitely CP forward of CG)

Appropriate for this thread, Fliskits has T-shrits for both occurances.
Stable/Unstable

 

[jflis]

Appropriate for this thread, Fliskits has T-shrits for both occurances.
Stable/Unstable

I was just going to say...

We have a shirt for that...

 

[bobkrech]

My kind of shirt.

Bob

 

[bandman444]

I think what ted said is the biggest point for this is that the trust NEEDS to be centered, when your building it you need to be able to find the cg, not just longatudaly but horizontlely aswell. Once you find the exact location of the cg then its all about lining up the motor mount right at it. Hope that helps.

I need to pick up one of those tshirts

 

[gagreen]

do you mean just a massive up scaled project like this version of the spitfire https://njgoldens.webs.com/spitfireproject.htm

just ran across this one last night pretty intense