This is a cool looking rocket- anyone have more details on this one?

This blog post has some references (including one back to Jerry's site). http://rocketdungeon.blogspot.com/2...t.html#comments

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- Dick
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Looks like an engine off a STAR WARS Y-Wing.
Not bad...

-Brain
Aim for the sucker holes.

The streamer stabilization method (see Figure 23 on page 20 here: http://www.ninfinger.org/rockets/ca...70semroc28.html ) that is discussed in the technical information section of Semroc Astronautic's May 1970 issue of Astronautic Modeler would make for some wild models (and wild flights, too, if one streamer tore loose from its outrigger during powered flight!). :-)

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NAR #54895 SR

It looks to me like streamer stabilization is another form of drag stabilization, but I can't visualize it relying on base drag like other drag stabilized rockets do. One can intuitively grasp its effectiveness as soon as one sees a simple graphic that illustrates the setup, though. But just out of curiosity, what is the aerodynamic process or mechanism that trailing streamers employ to produce the stability, anyway? How do they do it?

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SAM # 0011

They use balanced leverage. The drag force of each of the four (or three) streamers is magnified (with respect to the rocket body) by being transmitted through the "lever" (moment arm) of each outrigger, just like the balance of forces on a see-saw:

Mass X Distance from fulcrum = Mass X Distance from fulcrum

The streamer-stabilized rocket has these forces acting on two perpendicular "see-saws" (whose fulcrums are where the rocket's pitch and yaw axes cross) instead of just one as a see-saw does. That is why the loss of all or most of one streamer from its outrigger could be disastrous, because it would allow the (no longer counterbalanced) force of the opposite streamer/outrigger to make the rocket veer in the direction of the remaining streamer on that "see-saw" (which pivots about either the pitch or yaw axis that passes through the model).

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All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

So how did Goddard (and I suppose by inheritance Flis) do it?

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"The complexity of living is eminently favored to the simplicity of not."

"On calm days, with a judicious dose of luck."

A "nose drive" (tractor) rocket is neutrally stable (or nearly so) because the restoring forces are small. They have pendulum stability, but the bottom end of the pendulum, once kicked out of line, causes the forward motor to pull the rocket along in its new orientation. Skyrockets overcome this through their high acceleration, which gives them a strong vector along the thrust line (the wind does make them veer, but at their velocities their dominant motion is along the thrust line).

I saw this at work in heavy, slowly-accelerating stick-stabilized rockets that I built--even slight air movements caused large deflections in their trajectories because the wind vector was a significant fraction of their thrust vector (the wind speed was comparable to the rockets' speed during early ascent). The far ends of their sticks "fish-tailed" quite a bit because they didn't have the aerodynamic "authority" of fins, which produce larger restoring forces.

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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

The original Goddard rocket was not stable.

The FlisKits model of it is because the CG is in front of the CP. The rear mounted "fuel tank" is draggy and empty (lightweight.)


Bill