What Became Of The Launch Pad TALOS???

TopRamen said:

I'll be doing it in BT-80, but I probably will not do a Build Thread.
Maybe I'll show How I make the Nose Cone, but other than that I don't want to make a Thread where all I do is argue with Folks over how much things weigh. That's all build Threads ever devolve into, and it causes me to dislike Folks that I would otherwise get along with just fine.
I'm going to make it so that the Upper two Fin Sets, or maybe just one of them, have Axles and Range of Motion, and I don't want to be dissuaded from doing that by People worrying me about Design Principles or CG and CP concerns. It's not like I'm going to show up at their next "Club Launch" and risk hurting People with my untested Rocket, nor am I going to launch it with Spectators til' it has flown a couple of times safely.
I also get sick of hearing about, "The Guy that overbuilt his TLP Kit, and it did a whirlygig and landshark Cruise Missile and almost took out a Church full of Nuns and a Preschool before finally coming to Rest in the Windshield of a Schoolbus."
Nope, definitely no Build Thread, but when it is done, I will present it here in all its Glory, complete with Successful or Unsuccessful Video of it's Maiden Flight.
Proof will just have to be in the Pudding, or something like that.
AFTER it flies, maybe I'll do a "Sim" on it and share the File, or show how I did the Articulation for the Fins.

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Fair nuff!

Adrian

TopRamen said:

I'll be doing it in BT-80, but I probably will not do a Build Thread.
Maybe I'll show How I make the Nose Cone, but other than that I don't want to make a Thread where all I do is argue with Folks over how much things weigh. That's all build Threads ever devolve into, and it causes me to dislike Folks that I would otherwise get along with just fine.
I'm going to make it so that the Upper two Fin Sets, or maybe just one of them, have Axles and Range of Motion, and I don't want to be dissuaded from doing that by People worrying me about Design Principles or CG and CP concerns. It's not like I'm going to show up at their next "Club Launch" and risk hurting People with my untested Rocket, nor am I going to launch it with Spectators til' it has flown a couple of times safely.
I also get sick of hearing about, "The Guy that overbuilt his TLP Kit, and it did a whirlygig and landshark Cruise Missile and almost took out a Church full of Nuns and a Preschool before finally coming to Rest in the Windshield of a Schoolbus."
Nope, definitely no Build Thread, but when it is done, I will present it here in all its Glory, complete with Successful or Unsuccessful Video of it's Maiden Flight.
Proof will just have to be in the Pudding, or something like that.
AFTER it flies, maybe I'll do a "Sim" on it and share the File, or show how I did the Articulation for the Fins.
Probably take me atleast 6 Months to make this happen.

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You could always take pics along the way, then when it works do a retrospective build thread. When it has already flown fine, and it gets all posted in the span of an hour there will be little room for griping. I understand not wanting to do a build thread though, cuts into the build tome too.

Looking forward to tye product either way.

Cl(VII) said:

You could always take pics along the way, then when it works do a retrospective build thread. When it has already flown fine, and it gets all posted in the span of an hour there will be little room for griping. I understand not wanting to do a build thread though, cuts into the build tome too.

Looking forward to tye product either way.

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I always take plenty of Pics' of everything I put together for my own knowledge, so I can revisit and review stuff.
Yeah, if it all works out I'll show how it was done. I am goiung to start the build in the next couple of Weeks, as soon as I get the two Current Scratch Builds off my Bench. I already have the Body Tubes and am tinkering with the Actuators. I found a Pic' on one of my miscelaneous Searches for Pics' of Missile stuff that showed me how to make the internals, and Axle with an Armature on it and for my Purposes, Springs instead of Connecting Rods to Servos or Hydraulics. I'll just need enough Range of Motion to dampen Weathercocking and enough Torsion to keep them straight on. I NEVER fly in the Wind with Rockets this size anyway, but sometimes it's windy a few hundred feet up and you can't detect that from the Ground without the help of a Sounding Rocket or some other such Magic.

I think it is right that I clarify something.
Although I made some negative Comments about Weight and such, I have recently learned how to use lightweight FG Cloth, thanks to member JeromeK99, and I will be taking every pain possible to keep this thing as light as I can.
I won't need to use any Basswood or Plywood, as I can now just do some .75oz Cloth over Skeletonized Balsa.
I have been wanting to do this build as a 3x24mm, but it is going to be more practical in 29mm, but built light enough to fly on 24mm Composites with an Adaptor, so that is my Goal, keep it around 20oz. without Motors.

As evidenced by this Graphic Rendering from one of the previously afforementioned Links, the Body Tube will have to feature a Transition Section, and will not be straight 2.6". More like 3" down to 2.6" for modeling purposes.
I have a good handle on the Nose Cone, making it out of a PNC-80BB with a Paper Hat inside of a PNC-80 with the end cut off.
I also will be trying to make one using the Tail Cone from an Estes V2 Kit.

View attachment 246803

In Fantastic Four, Rise Of The Silver Surfer, they shoot miniature TALOS Missiles at Silver Surfer and his Board soaks them up.
Perhaps that's what happened to TLPs' TALOS???

I don't understand why there are not more People that want to make a Model of this Rocket and fly it.
I'm befuddled.?????

There actually was one - I built the prototype for a current vendor and flew it (I'm not sure I should mention who made it as it never made it to market). Was smallish (2") paper/wood. Problem is I could never make it satisfactorily stable. The forward wings played hob. when you have a 2" rocket that is about 36" long with 8oz of nose weight and it is still not stable, perhaps it is not the best idea.

Other than wanting to attend LDRS 34 as a Spectator, I'll probably never attend a "Club Launch" or face the Scrutiny of an RSO, so if mine goes crazy off the Rail, my Son and myself will be the only ones there to see it or put at any risk.
The problem with Hobby Rocketry nowadays is that nearly nobody takes any chances, and everybody is so hung up on "Sims" that they never actually build and fly anything. It really turns me off, but I don't let it phase me. If I ever do something unsafe, I won't talk about it here, even if it is awesome and amazing. I'm pretty certain that the TALOS can be made to fly safely.

Whether it succeeds or fails, when it is all said and done I will ofcourse share the Video here.

Well look at that! Some Peace Loving Fudgeball got this Thread down to three Stars.
Whoever you are that rated my TALOS Thread 1 Star, I can't wait to rub a Successful Launch in your Face.

TopRamen said:

Other than wanting to attend LDRS 34 as a Spectator, I'll probably never attend a "Club Launch" or face the Scrutiny of an RSO, so if mine goes crazy off the Rail, my Son and myself will be the only ones there to see it or put at any risk.
The problem with Hobby Rocketry nowadays is that nearly nobody takes any chances, and everybody is so hung up on "Sims" that they never actually build and fly anything. It really turns me off, but I don't let it phase me. If I ever do something unsafe, I won't talk about it here, even if it is awesome and amazing. I'm pretty certain that the TALOS can be made to fly safely.

Whether it succeeds or fails, when it is all said and done I will ofcourse share the Video here.

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I agree to a point... and it's good that you realize that you need to fly "unproven" designs in seclusion, without a crowd to put at risk. Just don't neglect your own safety or your sons.

In a way, I agree with you about the reliance on sims and "overemphasis" of them (misprioritizing might be a better word). NO sim is 100% accurate... sims are only as good as the assumptions made in their programming... and of course the validity of the input data compounds this. I remember one of the most interesting "wake up call" moments for me when it came to sims was when the "Mercury Joe" M flight went unstable and crashed... (the video is on the net) The sims said the flight would work fine... unfortunately, there was an error in the input, leading to the erroneous interpretation of the stability margin... instead of the stability being expressed in calibers of stability based on the larger main body tube of the rocket, the program had defaulted to using the caliber of stability based on the first tube in the sim, which was the "tiny" launch escape rocket tube size... so when the program said "1.4 calibers of stability" it wasn't based on a roughly 12 inch main body tube, but on 1-2 inch diameter (thereabouts) LES motor tube at the top of the tower... hence the CG/CP were actually practically on top of each other, creating neutral stability at liftoff-- once the rocket was in flight and ended up getting a significant angle of attack, the CP moved ahead of the CG and the rocket went completely unstable mid-powered-flight.

You are correct-- sims are a wonderful tool... but greatly rely on the validity and accuracy of the data input... and even then, with "complete fidelity" of the data, it is STILL an "approximation" of the performance, because there are basic assumptions made in the programming to approximate how the sim interprets how "real life" actually works, and mimics that performance in the simulation. Tim Van Milligan has alluded to this several times in various articles about the "RockSim" program iterations... and as the assumptions and methodology used to calculate and simulate various effects and behaviors in flight is improved, those are incorporated into the program and improve on the simulation... but at best, a simulation will ONLY be an approximation of the flight... not absolute prediction. Sims have their place, but they aren't the be-all, end-all of the story... real life results will ALWAYS differ somewhat from the predicted behavior in the sim... no matter how good sims might become, because some variables are simply "unquantifiable".

I also agree that Talos can be made to fly safely... if we can make as ungainly a vehicle as the shuttle fly safely in model form (with its off-center CG and extremely unpredictable CP due to the sidemount configuration, delta wings, etc) then there's really no reason Talos CAN'T be made to fly safely. Additional noseweight for shifting the CG forward is only one tool in the builder's arsenal-- pivoting front fins can eliminate the forward CP shift of the forward fins, supplemental slip-in or enlarged rear fins to "overpower" the forward fins, or some combination thereof, can be used to rectify the issues created by the forward fins in the design.

It's just a matter of the choices and tradeoffs the designer makes and his skill and understanding of the issues and how those tradeoffs and choices affect the performance of the model in flight.

Later and best of luck, and wonderful observations and points you made there!

OL JR

TopRamen said:

Well look at that! Some Peace Loving Fudgeball got this Thread down to three Stars.
Whoever you are that rated my TALOS Thread 1 Star, I can't wait to rub a Successful Launch in your Face.

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Umm...kay... REALLY??

You decry the over-focus on simulations, but then go on a rant over your "star" rating of the thread??

By the way, just for the record in case you were wondering, *I* had NOTHING to do with it... I've been following your thread here and there as it comes up in "new posts" with some interest, and I'm interested to see the fruits of your efforts and willing to contribute anything that could be helpful for consideration, but I'm pretty ambivalent about it... not exactly *my* cup of tea but I think it's a GREAT project for you, since this sort of thing seems right up your alley... It is interesting and I'm looking forward to your efforts and success (or what there is to be learned from the efforts).

Plus, I absolutely DESPISE the "rate this thread" type nonsense, thumbs up, thumbs down, "likes", and all other sort of "mob rule" type CRAP... so I don't do any of that sort of garbage...

Keep going and work hard on your project, and please keep those of us interested in your efforts informed, and don't get too wrapped up in the accolades or sniping from the "peanut gallery", which ultimately is of NO practical value whatsoever and has little/no impact on the outcome (or shouldn't).

Later and best of luck! Looking forward to it! OL JR

The test flights of the Talos were not simply unstable, they did a whole lot of low level skywriting. The big honking forward fins on a Talos were the problem. Keep in mind that a real Talos had a whole lot of electronics to steer it and correct for wild assed flights. We make a stupid mistake when we say "but the real one flies cool" - Not picking on Luke, but the Space shuttle flies well as there is an extraordinary amount of avionics dedicated to that goal. Yes, as Luke noted, we can play games with it and end up with something that resembles a Talos, however may be so far changed that it is no longer even sport scale.

Folks often forget that these surface to air missiles are designed unstable. We try to overcompensate by adding tons of nose weight. Then we end up with a heavy ballistic projectile if there is a recovery failure. Until someone can find a way to effectively stabilize a Talos, I doubt any vendor is going to sell one that might place them at legal risk.

One option to make a flyable Talos might be to put the forward fins on a pivot. This has the effect of virtually refusing the forward fin area to about 15% or so. Details here.

https://www.apogeerockets.com/downloads/Newsletter150.pdf

IIRC, the forward fine the on the Talos serve as fixed wings and are not actuated. This is still be an option, if not exactly scale. You could arrange for the forward fins to lock when on display.

tab28682 said:

One option to make a flyable Talos might be to put the forward fins on a pivot. This has the effect of virtually refusing the forward fin area to about 15% or so. Details here.

https://www.apogeerockets.com/downloads/Newsletter150.pdf

IIRC, the forward fine the on the Talos serve as fixed wings and are not actuated. This is still be an option, if not exactly scale. You could arrange for the forward fins to lock when on display.

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EXACTLY!!! Which is why I mentioned it in my previous post!

Thanks! OL JR

H_Rocket said:

The test flights of the Talos were not simply unstable, they did a whole lot of low level skywriting. The big honking forward fins on a Talos were the problem. Keep in mind that a real Talos had a whole lot of electronics to steer it and correct for wild assed flights. We make a stupid mistake when we say "but the real one flies cool" - Not picking on Luke, but the Space shuttle flies well as there is an extraordinary amount of avionics dedicated to that goal. Yes, as Luke noted, we can play games with it and end up with something that resembles a Talos, however may be so far changed that it is no longer even sport scale.

Folks often forget that these surface to air missiles are designed unstable. We try to overcompensate by adding tons of nose weight. Then we end up with a heavy ballistic projectile if there is a recovery failure. Until someone can find a way to effectively stabilize a Talos, I doubt and vendor is going to sell one that might place them at legal risk.

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Yes, shuttle flies well due to active guidance, as does the real Talos... BUT...

I was talking about MODEL versions. Virtually every one I've ever seen (with one exception I can think of) flies due to modification of the actual shuttle configuration to account for the non-axisymmetric design and sidemount configuration of the shuttle stack... using off-center motor(s) placed in the ET and/or SRB's, (and some with in the SSME locations as well, if for little else but "effect") and in MOST cases, using supplementary fins installed in the back end of the SRB's (Dr. Zooch Flame Fins, Estes slide-in fin units, etc.)

These supplementary fins shift the CG/CP relationship to a stable configuration. One COULD engineer a Talos with a slide-in supplementary fin unit with some very large aft-end clear fins to simply overpower the forward fins, which in combination with noseweight (probably a considerable amount) could make the rocket stable. One could also make the front fins pivotable, which has been done quite successfully, to minimize or even eliminate their effect on the CP, depending on how it's executed. One could also use some combination of all three methods, including oversize or supplementary rear fins ( slip-on or slide-in clear fins, or enlarged from scale aft fins, coupled with undersized and pivoting front fins, with enough nose weight added to make the thing stable.

I specifically and intentionally DID NOT mention any type of "active stabilization system" since it's not germane to the discussion as it stands... and from what I've seen, such systems are best applied to finless or marginally-stable but basically "easy to stabilize" rocket designs, not ones that are "inherently passively unstable" to begin with... that's why even the Ares I design would probably want to "swap ends" in a gimbaled motor active stabilization setup (after burnout anyway), whereas a Vanguard does not, despite both being finless...

later! OL JR

The question to me with the pivoting fins is: Do you make both the sustainer sets pivot? I've never tried this with canards in any fashion. However on a Talos, as most people think of it, there are three sets of fairly large fins. Might be talking out of the wrong end of my GI tract here, but I wonder what value simply pivoting the front fins would be? Of course you could build a model of just the sustainer and try that.

For such a darn ugly rocket, why are so many of us in love with trying to fly the beast?

In the prototype I worked with, I had almost 6oz of nose weight in a rocket that was 2" in diameter and under 3' long. We sort of abandoned the project as there did not seem to be a way to stabilize it.

H_Rocket said:

The question to me with the pivoting fins is: Do you make both the sustainer sets pivot? I've never tried this with canards in any fashion. However on a Talos, as most people think of it, there are three sets of fairly large fins. Might be talking out of the wrong end of my GI tract here, but I wonder what value simply pivoting the front fins would be? Of course you could build a model of just the sustainer and try that.

For such a darn ugly rocket, why are so many of us in love with trying to fly the beast?

In the prototype I worked with, I had almost 6oz of nose weight in a rocket that was 2" in diameter and under 3' long. We sort of abandoned the project as there did not seem to be a way to stabilize it.

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I think just making the forward fins pivot is going to reduce the nose weight needed tremendously. I would test fly a boilerplate model with the forward fins pivoting and see what it takes to make it stable.

With the forward fins virtually mostly removed by making them pivot, the rest of it is not much worse than an AMRAAM.

H_Rocket said:

The question to me with the pivoting fins is: Do you make both the sustainer sets pivot? I've never tried this with canards in any fashion. However on a Talos, as most people think of it, there are three sets of fairly large fins. Might be talking out of the wrong end of my GI tract here, but I wonder what value simply pivoting the front fins would be? Of course you could build a model of just the sustainer and try that.

For such a darn ugly rocket, why are so many of us in love with trying to fly the beast?

In the prototype I worked with, I had almost 6oz of nose weight in a rocket that was 2" in diameter and under 3' long. We sort of abandoned the project as there did not seem to be a way to stabilize it.

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Okay...

The "secret" to reducing/eliminating the CP effects from forward fins by pivoting them is to place the pivot "axle" as FAR FORWARD on the fin as possible... BECAUSE- anything FORWARD of the pivot point MUST BE ADDED TO THE SIMULATION TO CALCULATE CP AS IF THEY WERE FORWARD FIXED FINS OF THAT SIZE/SHAPE. What this means is, if the pivot point is placed at say the 1/4 chord line (1/4 of the way back along the length of the fin root edge from the pointed leading edge to the back end of the fin root edge) then the surface area perpendicular to the tube and ahead of the pivot point (the part of the fin forward of the pivot axle plane) will still affect the CP just as if it were a fixed (glued on) forward fin of that size and shape. The rest of the fin BEHIND the pivot axle plane will NOT affect the CP because it is free to pivot. The reason it works like this is because the part of the fin in front of the pivot axle plane still generates SOME force which is overcome by the back part of the fin pivoting into the airflow, but that generates some torque or lift in the time between the force acting on the fin to pivot it, and the time it actually pivots directly into the airflow. In reality it's probably less, BUT the way to correctly simulate and locate the CP (by your favorite desired methodology or simulation program) is to consider all parts of the fin ahead of the pivot point plane to be a "fixed fin" for CP calculations. Thus, to ABSOLUTELY minimize the aerodynamic effects of the fin area ahead of the pivot axle plane, the pivot axle SHOULD be as far forward on the fin as possible... theoretically, having the pivot point at the extreme front of the fin, should eliminate their influence on CP location entirely (of course in reality it doesn't completely, if for nothing else due to drag). Of course there's a matter of practicality involved... it's helpful to have enough of the fin structure to make a long enough axle to embed into the fin for the fin to pivot on. It's also a given that the axles have to be on SLIGHTLY different planes, one slightly lower than the other, so they "miss each other" inside the tube (since the axles will have to cross over each other at 90 degree angles, since opposing pairs of fins share the same pivot axle...) The other issue is ENSURING that the fins can PIVOT FREELY, even under heavy acceleration g-forces and aerodynamic drag pushing them backwards, which COULD cause the axle to flex and possibly allow the fins to "bind up" against the tube, which would prevent them from pivoting freely in the airflow with differing angle of attack of the nose cone to the direction of flight, or angle of attack of the airflow moving past the rocket flying through it (due to wind). If the fins "bind up" under aero-loads or due to gee forces flexing the axles enough that the root edges bind up against the tube, the fins will basically act like glued-on fixed fins, and not happy things will result.

It's not impossible, but it IS an engineering challenge that one must be aware of and address sufficiently in the design. Slippery plastic on the fin roots (to prevent binding) and leaving a sufficient amount of clearance, along with a large enough, stiff enough, and well-lubricated freely-turning axle to prevent "sagging" and binding up...

The rocket sans the front fins basically looks like a gap-staged two-stage model rocket... so it shouldn't be THAT difficult to make the thing stable. Pivoting the mid-mount fins shouldn't be necessary but it is certainly possible... just as pivoting the front fins. With proper design of the pivoting fins, it may well be possible to design the rocket with little or no additional noseweight...

Of course there's only about a thousand different ways this could be built-- the tradeoffs, materials, specific component design, etc. would all greatly depend on the priorities, skills, and tradeoffs the designer and builder makes. But there's absolutely no reason whatsoever that it "CANNOT" be done!

Later! OL JR

Interesting thought on pivoting the fin. Since the fins taper back from the most forward locus, Luke's requirement is relatively easy to meet with respect to the pivot point. The tricky part is how to make a strong enough pivot on a small scale - easy enough to do, the question is can it be done afford-ably (if you want to make a kit).

H_Rocket said:

Interesting thought on pivoting the fin. Since the fins taper back from the most forward locus, Luke's requirement is relatively easy to meet with respect to the pivot point. The tricky part is how to make a strong enough pivot on a small scale - easy enough to do, the question is can it be done afford-ably (if you want to make a kit).

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I would think that brass tubing, for a tube-within-a-tube type bearing would be doable... strength from shape and all that, and still pretty lightweight. Epoxy the tube into a slot in the fin material... would also recommend a poly washer between the fin and body tube, placed over the axle, to create a gap between the pivoting fin and the body tube and maintain that gap (a plastic washer will also help to "lubricate" the fin so it pivots smoothly against the tube).

Later! OL JR

I would think for an LPR version, use a 1/8 launch lug...make symmetric holes to pass the lug through, glue on the inside (reaching down with a dowel to apply the glue), then trim the ends. Have small notches in the fins, use a 1/8 wood dowel through the launch lug...the dowel attaches to the fins. Simple, no specialized parts needed, but robust enough and shouldn't have any need of plastic or lubricant since launch lugs by their very nature have to be pretty smooth inside.

FC

Does CP really matter if there is absolutely NO Wind?
Anyway, thanks Luke for the Info about putting the Pivot Point at the Front of the Wings, that makes sense, and changes things a little bit, but is still doable.
As far as pulling the CP back as far as possible, I think what I will do is make this variant of the Missile for flying purposes, then make the smaller finned Booster for Display only.

TopRamen said:

Does CP really matter if there is absolutely NO Wind?
Anyway, thanks Luke for the Info about putting the Pivot Point at the Front of the Wings, that makes sense, and changes things a little bit, but is still doable.
As far as pulling the CP back as far as possible, I think what I will do is make this variant of the Missile for flying purposes, then make the smaller finned Booster for Display only.

View attachment 247822

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The CP still matters and always matters in a non guided rocket. Launch rod whip if lugs are used, slight asymmetries in the motor nozzle and thrust, slight asymmetries in the build all can disturb the perfect path you are imagining.

tab28682 said:

The CP still matters and always matters in a non guided rocket. Launch rod whip if lugs are used, slight asymmetries in the motor nozzle and thrust, slight asymmetries in the build all can disturb the perfect path you are imagining.

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I'de never launch a Rocket of this size from a Rod! I hate Launch Rods, and only use them anymore for 13mm Models and smaller.
Launch Rods suck IMO. My last few 24mm Rockets fly great off the 1010 Rail, and I don't have to worry about "Whip".

It doesn't matter if you use a launch rod or not...you must still have the traditional stable CG/CP relationship in an unguided rocket.

Otherwise, flying it is like trying to balance a sharpened pencil on its tip...you can do it for a very short length of time.

FC

TopRamen said:

I'de never launch a Rocket of this size from a Rod! I hate Launch Rods, and only use them anymore for 13mm Models and smaller.
Launch Rods suck IMO. My last few 24mm Rockets fly great off the 1010 Rail, and I don't have to worry about "Whip".

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Note that I covered that possibility by saying IF you use a launch rod. The other issues still apply. If the model not statically stable, the least disturbance can result in a divergent flight path even if the model has neutral stability. The more negative stability a model has, the more energetic the divergence is....and it WILL diverge.

I like to push the envelope as much as anyone, but I never try to repeal the laws of aerodynamics using wishful thnking....

TopRamen said:

Does CP really matter if there is absolutely NO Wind?
Anyway, thanks Luke for the Info about putting the Pivot Point at the Front of the Wings, that makes sense, and changes things a little bit, but is still doable.
As far as pulling the CP back as far as possible, I think what I will do is make this variant of the Missile for flying purposes, then make the smaller finned Booster for Display only.

View attachment 247822

Click to expand...

Yeah, CP REALLY matters REGARDLESS of wind...

There really isn't ever "absolutely NO wind"... even if its perfectly still at the surface, you'll still have winds aloft, of some type and intensity, and who knows from what direction... air currents, all sorts of stuff... CP HAS to be behind the CG enough to maintain stability. Remember that CP moves forward with increasing angle of attack-- this means that as a rocket "tips over" in flight, if the CP is BARELY behind the CG, it can shift in front of it, and the rocket can go COMPLETELY UNSTABLE... I've seen it. There's always SOMETHING that tends to push the nose of the rocket around, no matter HOW carefully built and no matter how "perfect" the conditions... slightly asymmetric thrust, tiny variations in the centering of the motor mount or axis of the motor tube, slight variations in the fins, their aerodynamics, or how they're attached to the tube... slight drag from the launch lug or a tiny bit of rod whip or tip-off... just about anything can cause a problem when you're talking about a rocket with neutral stability (CP and CG too close together but technically CP behind the CG, just not far enough).

Later! OL JR

TopRamen said:

I'de never launch a Rocket of this size from a Rod! I hate Launch Rods, and only use them anymore for 13mm Models and smaller.
Launch Rods suck IMO. My last few 24mm Rockets fly great off the 1010 Rail, and I don't have to worry about "Whip".

Click to expand...

Yes, but the fact is, there's STILL things that can cause the flight path to deviate... torque from the ignition or thrust of the rocket up the rail, etc...

It's those "unknown unknowns" that get you... and you cannot eliminate them. You have to build enough margin into your design to accommodate them...

Later! OL JR

I solved the Problem of making the Wings swivel freely. Since they will Pivot at the Top like Luke wisely suggested, they won't need springs to keep them straight, Gravity and Drag willbe plenty. I also got rid of the need for Axles, so the Laundry won't have to go in the Middle of the Model screwing up the CG.
Took me about 15 Minutes in the Agro-Bins at Ace Hardware to come up with something, and I think you Folks are going to be pleasantly surprised at what I have designed.
I just realized that I still need one more trip back to the Bins to get some more tiny Pieces that I considered, but decided not to get, and then I can assemble the Prototype of the Articulated Wing Section.
This will work for other Rockets too, so it will open up a bunch of new avenues.
I also got to thinking about TLPs Matra Magic Model. That's got an aweful lot of Fins/Wings up top too, yet it flies good.