Ultraman VTOL Plane (Space Booster Version)

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BigMacDaddy

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Saw someone post about an Ultraman VTOL plane model he saw in a museum. Did a bit of searching and found out there is a booster modified version of this so was wondering if it might be worth it to make this relatively obscure sci-fit rocket. Kinda a cool retro look with a ring tail and some other kinda cool details. Given my recent luck with smallish 3D printed rockets I am pretty sure I could make this stable. What do you guys think -- worth it?

Was thinking to make this somewhat larger than the past models I 3D printed and include a pair of 18mm engines which should be plenty to lift this 37x26x16cm rocket (roughly - boosters are BT50 tubes). Rough version for 3D printing below (I added much more detail to the boosters since this morning - I was thinking to make the boosters decorative, no need for 5 engines on this thing).

https://ultra.fandom.com/wiki/Jet_VTOL (look for Space VTOL)

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I vote "Worth It"

Ultraman... that brings back some memories from my youth.


Great quote to a downed aircrew’s relative

”There‘s no sign of him here which may mean that he didn’t get killed.”

oh gee, that makes me feel sooooo much better!

not sure if that was bad writing or bad translation or both.
 
I vote "Worth It"

Ultraman... that brings back some memories from my youth.


The orange spandex uniforms with the ties sort of makes me think of a cross between Spanish Matadors, the Texas Long Horn Marching bands, and the Ice Capades.

somehow Space Force working/flying uniforms with neck ties doesn’t work for me. In SAC we had colored scarves that we would wear under our flight suits that I thought looked cool (I have to admit, I just FELT cool wearing a flight suit.). But neckties, meh.

oh… yeah, back to the rocket.

definitely a go on the build. I am a fan of asymmetric fins, this might be a bit much as it is kinda short and stubby. you may need to take some artistic/engineering license and either place the wings lower (maybe a single piece wing that crosses UNDER the tube..). Other options include adding a ventral fin or extending the ring around a bit more and making it longer (nose to tail)
 
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I am a fan of asymmetric fins, this might be a bit much as it is kinda short and stubby.

Yes, was definitely thinking that the drag on top might make this arc up over its back a fair bit. I was hoping that the front little canard fins might help some.

What if I move the main engine pair up a little bit in the body? How much would be too much?

I could also angle the rear wings down 15 degrees which might help a bit but otherwise need to add some drag to bottom of rocket.

I wonder about some fuel tanks or something on bottom of rocket. When they built the rocket in the clip there were these parts of the sled that I thought were going to be part of the rocket (can see in picture below). Do you think if I built these into the model (probably made symmetric with cones on both ends) that these would help counter the ring fin drag with some bottom drag?

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Here are the close to final booster details -- on a whim I made these so they can fit mini engines (let your imagination run wild about multi-stage clusters). I also realized that the top booster is smaller so dropped that to a BT20. Still need to do some work to the engine retainer caps.

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And here are the possible drag-inducing bottom fuel tanks inspired by the sled details that looked like they would be added to the space booster version of this VTOL... Do you think these are enough to offset that ring tail?

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Instead of adding more draggy components, you could offset the motor mount slightly so it's center line (C/L) is above the rockets center of gravity (CG), or cant the motor so it's C/L is slightly above the rocket CG .... just a thought.

That would induce a moment, to offset the moment created due to drag.

You can actually offset the motor using Open Rocket. Select a 2 motor cluster configuration, then select "Split Cluster". Then you can move that motor where you want it.

In the stubby Alpha below I deleted one of the cluster motors, then moved the remaining motor.

You could calculate the moment created on the rocket due to offset drag, then calculate the moment due to the offset motor and adjust the offset so the moments counteract each other.

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And here are the possible drag-inducing bottom fuel tanks inspired by the sled details that looked like they would be added to the space booster version of this VTOL... Do you think these are enough to offset that ring tail?
That's a big old "maybe". Things like this are very difficult to guess at. The tanks certainly should help, although adding more tail weight at the same time.
 
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I never saw the show but I did come accross collectibles over the years. Not this ship however. I just found out there are many recent products. Maybe someone should consider scaling a flying rocket with an existing figure. Since Ultraman is a giant, the rocket wouldn't have to be huge.
https://www.bigbadtoystore.com/Sear...&PageSize=20&SortOrder=BestSelling&Brand=4911
This vehicle also looks incredible! And very "do-able"!
https://www.bigbadtoystore.com/Product/VariationDetails/42234View attachment 482536
I saw that one as well and thought it looked even easier to make. There is some type of Saturn looking rocket at the start of episode 16. So funny that for this show they are literally using models for the space ships so our rockets could be 1:1 to the prototype. ;)
 
What do you guys think -- worth it?
Yes. And extra points if you can make it glide. There'd need to be a way to shift the CG aft after the coast to apogee, or the CP forward. Perhaps a spring loaded weight held forward by a burn-through string. Of (now this would be cool, but maybe overambitious) eject the ring and outer pods the move the CP up. That part tumbles down and the rest is placed in glide trim.
On a whim I made these so they can fit mini engines...
Remember that, since no two morots burn with exactly the same performance, putting them on fin tips is generally expected to cause sky writing. I do wish that Estes or someone would make certified zero thrust engines that are all delay/smoke grain. This would be a great model for those.

And here are the possible drag-inducing bottom fuel tanks inspired by the sled details that looked like they would be added to the space booster version of this VTOL... Do you think these are enough to offset that ring tail?
I'll go with what Neil said about this stuff being very hard to guess at. And I'm sure there are people better at guessing it than I am. But since I just can't resist putting my two cents in, I don't think that added ventral drag is needed. The anhedral you applied in other pictures seems like a good idea instead, even though that would make gliding a lot harder. And frankly, I'll bet you'd be OK with neither. I just wouldn't bet much.

Instead of adding more draggy components, you could offset the motor mount slightly so it's center line (C/L) is above the rockets center of gravity (CG), or cant the motor so it's C/L is slightly above the rocket CG .... just a thought.

That would induce a moment, to offset the moment created due to drag.
That only helps during the engine burn. Once the thrust is gone and you're coasting it's all lift and drag.
 
I wouldn't surprised if it did indeed need some additional ventral drag to offset what's above. But exactly how much, and how badly the rocket would tend to arc over without it, is anyone's guess.

Note that in addition to asymmetrical drag, that rocket will also have a somewhat off-axis CG, which those ventral pods would go a long way to correcting.

But hey, if you *really* want to solve the problem, just put a motor in that top pod. I can't quite tell if you're planning to do that or not.
 
I need to get back to this model -- need to finish up the designs of all the various components so I can print it.

On the draggy fuel tanks, I was actually considering doing a mini ring tail to connect through those bottom components to the rest of the ring tail -- obviously some artistic license here but what the heck it is a pretty uncommon version of a fictional rocket that very few people even know about...

Annoying they took down the videos on Youtube. I started watching a new Ultraman on Netflix or Hulu... could not stick to it but was cool to see some models of this plane / rocket in the museum in the show.
 
I finally started to print this model... The body is not tubular so I am 3D printing the whole thing (well fins are templates and will be cut from 2mm basswood - hint: templates are a good way to run out a roll of filament since they just need to print enough to be solid)...

This is gonna be 14" tall and will be pretty darn heavy. I am checking my limits for 3D printing full bodies of complex models like this that can be launched reasonably cheaply. I hope it stays at or under 200grams so I can launch with 2x 18mm C6-3 engines without using up my C5-3 super engines. Can you mix a C6-3 and C6-0 for a 2-engine cluster like this?

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Can you mix a C6-3 and C6-0 for a 2-engine cluster like this?

A very good question. Just having a quick comparison on the Estes site the Max thrust and thrust duration are the same so I'd say yes. I've tried it before, but a CATO took the model out, so no real help to you.
 
So still lots more finishing - wood and epoxy filler, sanding, some parts not glued on yet, etc... - but first build of model finished.

I am glad that I outfitted this with space for 2x 18mm engines since this is a heavy, short, fat rocket - around 14" long and 210 grams without engines (that is w/ 2oz of weight in nose which puts CG in front of wings).

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Can you mix a C6-3 and C6-0 for a 2-engine cluster like this?
I don't see why not, but then I also don't see why. You'd have to vent the ignition charge from the -0, and make sure not to vent the ejection charge from the -3. So you have to make darn sure to put the right engines in the right mounts, and build in a vent hole that holds up to the hot ignition gas and particles. And to what end?
 
I don't see why not, but then I also don't see why. You'd have to vent the ignition charge from the -0, and make sure not to vent the ejection charge from the -3. So you have to make darn sure to put the right engines in the right mounts, and build in a vent hole that holds up to the hot ignition gas and particles. And to what end?

Ah, good point-- I was actually thinking about how to manage the ejection charge so it would not be overkill but forgot that the -0 will also have a burn through that occurs too soon... Ok, 2x C6-3 or 2x 6-5 it is.
 
You could stuff the top of the -0 with dogbarf and tape over. That seems to work - and not count as a motor modification.

I have accidently lit a motor charge from the top (during a dual deploy test where I -thought- the motor was spent - but wasn't). It seems that there can be enough stray powder mixed in with the cap to sustain a burn. It does terrible, terrible things to the body of the rocket.
 
Ah, good point-- I was actually thinking about how to manage the ejection charge so it would not be overkill but forgot that the -0 will also have a burn through that occurs too soon... Ok, 2x C6-3 or 2x 6-5 it is.
Or, to reduce overpressure from two ejection charges, you could use one -3 and one -5. Still, there are plenty of cluster rockets loaded with matching engines and no problems. Don't overthink it (I say as if I don't overthink things day in and day out).
 
RE: mixing C6-3 and C6-0.

sure, but you need to keep track of which motor is which.

seal the C6-0 compartment, leave the C6-3 (or C5-3 if you need it) open to the ejection bay, this is your deployment motor.

the C6-0 is loosely friction fitted, just enough so it doesn’t fall out o the pad, when it burns out it gets ejected out the rear (make sure this is okay with your field rules.)

both the ejection “kick” and the drop in mass will give your bird a bit more altitude, probably not measure able.

it will probably kick out pretty low, so shouldn’t be too hard to find the casing.
 
The kick, yes. The mass reduction will hurt the altitude. Immeasurably, agreed, probably yes.

Once the rocket is up to speed, whatever that top speed is, greater inertia helps because it diminishes the effect of drag. That's why there's an optimum launch mass; more mass means a lower top speed and less mass means slowing down faster. But mass ejected after burnout only affects the latter.
 
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