Atlas-Able Semi-Scale Mid-Power

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lakeroadster

When in doubt... build hell-for-stout!
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The Atlas-Able was a unique rocket, with a horrible track record. Three launches were made, all three were failures.

Here's a semi-scale version that uses the 1-1/2 stage concept, (2) booster motors and (1) sustainer, all of which fire at launch like the real thing did.

Estes BP motors are planned: (2) D12-3's in the boosters (canted) and (1) E12-4 as the sustainer. When the D12's eject, the booster will fall away from the sustainer and recover on it's own parachute. Seconds later the E12 will eject the sustainer parachute.

Or... if the fit between the booster and sustainer is a loose slip fit there's a good chance the booster will drag separate stage once the the booster motor thrust stops.​

After stage separation occurs, the sustainer simulates as unstable.. but it won't be under power when staging occurs, and it will be at a high enough altitude as to not be a safety concern. The canted motors could be mounted slightly askew to induce spin during flight to add spin stability.... something to ponder.

I've also run simulations for other BP motors. The rocket could also be flown on composite motors, but I'm unsure as to if getting (4) to ignite at the same time would be feasible...

Sounds like a spectacular flight.

I just kind of visually threw together the model components into Open Rocket, just to see if the flight is feasible. I can later pull an actual photo of a real Atlas-Able into CAD to make the rocket proportions more to scale.

Thoughts?

2023-04-11 Atlas-Able Open Rocket Flight Simulation 1.5 Stage.jpg2023-04-11 Atlas-Able Open Staging Outline.jpg
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Here's the concept art that @Ez2cDave posted on this thread that sent me on this journey. The 1-1/2 stage concept is just too cool to not build a rocket that emulates it.

490978-062f9a9036e6d14715babfdc8eae6ac4.jpg

 
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The Atlas-Able was a unique rocket, with a horrible track record. Three launches were made, all three were failures.
So the operating precept here is,

“Four’s a charm”?
Simulation data shows stage separation occurs at 835 feet, and at that point the rocket is traveling at 14 mph. At that speed... What Me Worry?
At 14 mph I doubt base drag hack is gonna hack it, not sure if the biggest fins in the world would help.
 
Composite motors?
This is another build where I want to stay true to the original design concept, which had (2) booster motors, and (1) sustainer.

I don't see where I'd gain anything by using composite motors. :dontknow:There's the added complexity of getting (3) of them to ignite at the same time, and if that's overcome, additional altitude doesn't do anything but make the rocket so high up at staging that you can't really see what's happening from the ground. Plus... they cost more money.

Most folks want to maximize apogee when building rockets. I'm always wanting to keep it around 800 feet, under 1,000 feet, so I can visually see staging, chute deployment, etc.
 
Very Nifty. I have an uncompleted 1/35 Atlas Agena on the project table. (I got distracted by staged sounding rockets.) I spent a lot of time pondering how to do the stage and a half separation. I'll be watching you solutions. My booster motor plan was C11-0s with a little loose BP on top. That worked pretty well for my Titan IIIe.
 
Most folks want to maximize apogee when building rockets. I'm always wanting to keep it around 800 feet, under 1,000 feet, so I can visually see staging, chute deployment, etc
Nice to see someone else gets it!

For low and mid power, if you are an altitude chaser far better off going minimum diameter with the biggest motor that will fit.

Low power Model rocket staging is all about the challenge and the show. Need a stout spike burn on first stage motor(s) to get the behemoth off the rod or rail with authority, the a weak short tail to get it to stage low, and minimal motors in sustainer or intermediate stages .

That said, it was embarrassing when my Estes Apogee II staged ON the rod, and the booster slid back down nice and pretty on the pad.
 
Note stole... I borrowed it. And I brought my own "replaceable brush unit"... or should I say "the 3rd and 4th stage sub-ass'y."
Rename it “Dental Highgiene”

I don’t care what stage it is, please keep your “ass’y” out of my bathroom.
 
That said, it was embarrassing when my Estes Apogee II staged ON the rod, and the booster slid back down nice and pretty on the pad.

It's all about the color commentary....

Rocketeer Babar states: "And this rocket shows the concept of staging, and does so at an altitude where every detail of the process can be reviewed".
 
I don’t like to appear dumb but.....here goes. How can this rocket be stable with no fins? And what does the long narrow triangle at the back end of the rocket in the OR drawing mean?

There are a number of way to make a rocket stable, fins is one of those. There's also Gas Dynamic Stability, Roll Stability, and Base Drag Stability, to name a few. Think about a "Spool" rocket, and a "Pyramid" Rocket. Those don't have fins, yet they fly stable.

That being said, my version of the Atlas-Able is still in the design phase and has yet to be proven to be a stable design.

The cone at the back of the rocket is "The Open Rocket Base Drag Hack" <--- click to learn more.
 
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There are a number of way to make a rocket stable, fins is one of those. There's also Gas Dynamic Stability, Roll Stability, and Base Drag Stability, to name a few. Think about a "Spool" rocket, and a "Pyramid" Rocket. Those don't have fins, yet they fly stable.

That being said, my version of the Atlas-Able is still in the design phase and has yet to be proven to be a stable design.

The cone at the back of the rocket is "The Open Rocket Base Drag Hack" <--- click to learn more.
Thanks for the info. Base draghack info told me how wide to make the cone but not the length. obviously I have no experience with this in OR so I should experiment a bit. I’m presently Scratch building an AtlasV 551 with no fins and using the 5 SRBs as open topped tube fins. Have not yet drawn it into OR.
Thanks again.
 
Also if you would like to read the newsletter article that the hack is based on, you can download it from (Here).

A complete list of Apogee newsletters can be found (Here).
 
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