Oh, I have some of them. They do pop up for sale online from time to time.

While I know that military and professional research rockets sometimes use spin stabilization for some finless stages, I am not familiar with anyone ever doing it successfully with a model rocket.

MarkII

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SAM # 0011

Estes is supposed to be bringing back the A10-0T, but like many of their other promised product releases and re-releases, I'll believe it when I see it.



There was a thread on here awhile back about (or perhaps by) someone who had rigged up a short spinning launch tube that was rotated by an electric motor. He said that 18 mm motors with no fins (or nose cones) were fired from the spinning launch tube and that they flew straight. I don't remember what spin rate it used, but it shouldn't take a tremendous amount of rotation to get a short finless upper stage to fly stably. A short spin-stabilized upper stage is much less susceptible to "coning" than a long upper stage.

In 1999, I watched a Black Brant XII launch at the Poker Flat Research Range in Alaska. Its finless fourth stage (a Nihka rocket motor) had a very long payload section bolted to it. Even though it was spin-stabilized from the rotation imparted to it by the fin-equipped lower stages (Talos, M-50 Honest John, and Black Brant VC motors), the Nihka "corkscrewed" during its burn because the unusually long payload section had begun "coning"--we could easily see the Nihka motor's helical exhaust trail high overhead in the aurora-illuminated night sky. Fortunately, the mission was still successful (the peak altitude was just somewhat lower than planned) and the chemical release grenades and payload instrumentation all worked properly.

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Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

There is an Estes DOM winner that did it. The bottom stage had fins with angled tabs on them, to impart a spin. The upper stage had no fins, but by the time it fired and separated, the rocket was supposed to have enough spin to keep it going straight.

I don't know where to find it. Maybe someone else who knows what I'm talking about could post the plans. Very cool.

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"AND I hope they are from the planet of the "Chunk spunky Mary-Lou Retton clones". - Ironnerd

"Those who trade liberty for security have neither" - Benjamin Franklin

"Semroc is almost always the answer" - Stefanj

www.paulsavia.com

www.soundclick.com/paulsavia

Estes Industries Rocket Plan 128 - TAO

http://www.spacemodeling.org/JimZ/eirp128.htm

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Don
NAR 53455
"Carpe Diem"

Thank you for posting the plan! The name is very apt. I feel like an old nag now--the DOM contest has now become the DOQ (Design Of the Quarter) contest!

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

Thank you for all the great discussion, folks. Much food for thought.

Having recently built a Twin Taser, I am going to implement the Apogee II method on new two stagers that I build. However, on the Midget, the fins are sized to the tube and I don't want to resize the fins in order to make the tube longer.

I have seen that plan on JimZ's site, but I haven't studied it in detail. I'll really take a look at it now and maybe give it a try. A totally finless sustainer that is actually stable sounds really interesting.

MarkII

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SAM # 0011

I know this is an O-L-D thread, but it's not one whit less interesting--or useful--for all that. I've always found it interesting that the Estes Technical Report on Multi-Staging (Tech Report TR-2, see: http://www.ninfinger.org/rockets/EstesTR2.pdf ) mentions--on page 1, in the seventh paragraph--that "gimmicks such as pressure relief vents, etc., were tried, but none proved satisfactory," because Centuri's Pass-Port staging method--which utilized a vented external #7 tubing stage coupler--apparently worked just fine. (So does G. Harry Stine's vented gap-staging method [described and illustrated in his "Handbook of Model Rocketry"; upper stage motors separated from the first stage motors by up to 12" ignited with 100% reliability in 100 test flights], which Mark II mentioned in Reply #7 above.) Also:

Large-diameter models are shown ^without^ the interior first stage motor mount tube overlapping the cellophane tape-wrapped joint between the motors; the butt-joined motors are taped together, but the joint area is exposed (the stages' larger-diameter [BT-50 to BT-60 or so] airframe tubes are kept aligned by a stage coupler, glued into the front end of the first stage body tube), and:

Page three of the report also describes and shows (in Figure 8) a variation of the "cellophane-taped, first stage tube-overlapped motors joint," which is shown--early in the report--being used in minimum-diameter models. Instead of taping the motors together with cellophane tape (and friction-fitting them into their respective stage airframe tubes, using masking tape), this method--which is recommended for use only with Series I and Series III ("Shorty") lower stage motors (maybe it would also work with today's Series III, 13 mm diameter mini motors?)--involves taping the *outside* of the stages' joint (or joints), with rectangles of masking tape. It is considered "poor aerodynamic practice," but it is easier and quicker.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

Try it without any tape. Works for me.

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Clubs: BARC, MDRA

the old Centuri kits actually had an engine block at REAR of the booster, to prevent that from happening, good idea.

generally speaking, on Estes kits, like the old Vigilante we flew Sat, the booster engine will stick past the motor tube and then you wrap tape around the exterior joint at rear of booster.