Jeff L's unbaked design thread

[BABAR]

Or give it to @Daddyisabar

he’ll stick two more motors in the nacelles and fly it backwards as well!

 

[BABAR]

Looks very cool. I see a potential concern that the fins are so far off to one side. @BABAR likes to say "Symmetry is overrated" and he has lots of successful designs to prove it. I wonder if there any tricks to doing this sort of thing successfully that he might like to pass along.

Length is definitely your friend when you go Skwewy. that’s the down side here.

Estes original Enterprise rocket used Kirk’s Kobayashi Maru solution. To quote McCoy, “”He cheated.”*

Estes added a long forward boom with nose weight to make it stable.

you could build a sky blue boom and stick a heavy scale or super scale shuttle craft or a Tholian Webb ship at the front. Speaking of which, @neil_w did Gary ever get that Tholian ship to fly?

https://www.rocketreviews.com/estes-star-trek-starship-enterprise-frank-casey.html


*. https://en.wikipedia.org/wiki/Kobayashi_Maru

 

[Jeff Lassahn]

I was cleaning up some leftover odds-n-ends and accidentally made this:


It really looks like it ought to be something. Maybe like this:

 

[lakeroadster]

I was cleaning up some leftover odds-n-ends and accidentally made this:
View attachment 473305

It really looks like it ought to be something. Maybe like this:
View attachment 473306

It's got a lot of aero drag at the back, you can name it "The Dragster".

 

[jqavins]

It really looks like it ought to be something. Maybe like this:
View attachment 473306

Yes. Yes it does.

 

[Jeff Lassahn]

I've been doing a bunch of stuff with Space Shuttles recently. Since I haven't had enough enthusiasm to continue work on my 1:150 scale one, I'm thinking about going totally the other direction.

So instead of a big fancy hand crafted shuttle, here's a little silly one made from off the shelf parts. It's BT-5 tubes for the orbiter and the SRBs, and a BT-50 for the tank. Flies on 1/2A-T or A-T mini motors.

 

[kuririn]

Extra points if the shuttle glides.

 

[Jeff Lassahn]

The plan is for the shuttle to glide and everything else to have a streamer.

 

[BABAR]

I've been doing a bunch of stuff with Space Shuttles recently. Since I haven't had enough enthusiasm to continue work on my 1:150 scale one, I'm thinking about going totally the other direction.

So instead of a big fancy hand crafted shuttle, here's a little silly one made from off the shelf parts. It's BT-5 tubes for the orbiter and the SRBs, and a BT-50 for the tank. Flies on 1/2A-T or A-T mini motors.


View attachment 492738View attachment 492739View attachment 492740

I am not a scale dude. I think your model looks great just as pictured above. Unless you are going into a competition (which in the U.S. for scale models is what, once a year? Maybe other events I don't know about) the only person you need to impress is you.

FWIW (this may refute my statement above), a model that looks EXACTLY like the above (including relatively low definition decals, and only a few of them) would probably make a pretty popular kit.

Finally, if you build it like you say and it works, you are that much further ahead in (if you so desire) upscaling it and building it to scale.

Have fun!

 

[GlenP]

Maybe you could fashion some kind of SRB separation at ejection so the they come down on their own streamers and the central tank on a small chute? The SRB streamers could be stored in the ET but on an external shroud line to the middle of each SRB?

 

[Jeff Lassahn]

The Fabulous ThunderPenguin

 

[BABAR]

Extra points if the shuttle glides.

Big time extra points if the rest of the rocket glides

 

[jqavins]

Maybe name it Opus. He's always longed to fly.

 

[Jeff Lassahn]

Torellian Invader Mk II.
You know, that thing where somebody decides to reboot the series, and they tell the art department "make it look kinda like the original, but do your own thing"

 

[neil_w]

I miss this thread. Hey @Jeff Lassahn, got anything else cooking?

Torellian Invader Mk II.
You know, that thing where somebody decides to reboot the series, and they tell the art department "make it look kinda like the original, but do your own thing"

View attachment 557550

There are like 20 good ideas in there. With some tweaking and a good paint job it could be fantastic. I might be stealing borrowing "getting inspired by" some stuff in there.

The front is vaguely reminiscent of the ships in UFO that had one ginormous missile on their nose.

<googling>

Ah yes, here we go:


Yours, though, looks good, whereas that ship in UFO always looked ridiculous to me, even when I was a kid.

 

[lakeroadster]

I miss this thread. Hey @Jeff Lassahn, got anything else cooking?


There are like 20 good ideas in there. With some tweaking and a good paint job it could be fantastic. I might be stealing borrowing "getting inspired by" some stuff in there.

The front is vaguely reminiscent of the ships in UFO that had one ginormous missile on their nose.

<googling>

Ah yes, here we go:
View attachment 586690

Yours, though, looks good, whereas that ship in UFO always looked ridiculous to me, even when I was a kid.

It has some great visibility though. Kind of the AMC Pacer of the Sci-Fi Star Fighter genre....

 

[neil_w]

It has some great visibility though. Kind of the AMC Pacer of the Sci-Fi Star Fighter genre....

What do you call a Pacer with all its windows smashed?

Spoiler: see answer

Totaled!

 

[BABAR]

It is very pretty... if you could make it survive it'd be a winner.

External small shock cord attachment loop ventral tail end (presumably on same side as launch lug.). Just needed to be large enough to link a snap swivel or a cord loop.

for flight, run the shock cord between nose cone shoulder and rocket body (maybe a very small notch the length of the nose shoulder, enough so it slides in over the shock cord easily but not enough to vent).

cord runs the length of the rocket on the side near the rod or rail, almost invisible. The rocket ejects nose cone and laundry, body descends nose down.

for display, detach shock cord and stow on body.

 

[BABAR]

Aluminum foil tape wrapping around the inside edge of the rear plumes. Offers some protection, looks shiny, and shouldn't be too hard to clean either.

Biggest risk is those tips snapping off.

Mylar tape isn’t 100% fire proof, but would help.

 

[BABAR]

Trying out different lengths for the interplanetary ship.
The original -- longer -- and no really lets stay _way_ away from that reactor longer
View attachment 433027
Currently my favorite is the really long one.

Also thinking that maybe the radiator fins on the rear should be a ring instead of panels. Real spacecraft always use boring easy to make rectangular panels, but rings are cool.

put split rings on the back, specially windowed like Bail Out Bill, and put a side or front port for ejection charge.

you could do horizontal spin recovery On this.

https://www.rocketryforum.com/threads/bail-out-bill-and-the-horizontal-spin-recovery-rocket.147210/

 

[Jeff Lassahn]

I miss this thread. Hey @Jeff Lassahn, got anything else cooking?

Yes, I mean No, I mean Maybe...
it's been really busy recently between new job and family stuff.
Once I get past that and have some more time to do rocket things, my goals are:
1. actually fly this thing and see if it works or not
https://www.rocketryforum.com/threads/yet-another-space-shuttle.1793352. make progress on the aerodynamics code I'm supposedly patching into OpenRocket
3. mess around with 3D printing
and once all that's out of the way maybe I'll build something cool.

So... shrug?

Also there's an AMC Pacer sitting in our garage right now waiting for Kathy to get around to fixing it up. So be careful what you say around here lest you seem insufficiently respectful of the Pacer and bring down her wrath.

I really should go back to some of the Orion Starfighter sketches I made to go with that Torellian Invader.

 

[Hobie1dog]

I missed how you balance the shuttle to make it glide properly. Can you explain the way you do it? Thanks

 

[Jeff Lassahn]

The basics of setting up a glider for stable flight go something like this:
The center of gravity needs to be just slightly in front of the center of pressure for the pitch axis. This makes the glider stable in the same sense that making the CG forward of the CP makes a rocket stable.
But having the CG in front of the CP also makes the glider want to dive.
So the glider needs some up elevator trim to make it pitch up.
The combination of CG and elevator trim need to balance to make the glider fly well. How exactly they need to match depends on the details of the glider shape.

So, applying that to the shuttle...
For the shuttle's compound delta wing the CP is roughly at the bend where the main wing meets the strake. So while building the model I'm making sure the balance point is kinda close to there. If it's way off it will make trimming it later hard.
Fortunately, everything worked out pretty well, and the CG was close to where I want it without having to correct anything in the early parts of the build. I have a theory that this isn't just luck -- after all the real shuttle was designed to be balanced for glide, so models of it will likely have sane glide characteristics too.

When building the wings, I attached the elevons with about a 15 degree up angle. I just picked an angle that seemed right.

The very front of the shuttle nose on my design is a separate piece, you can see in this picture that it hasn't been attached yet. This gives me access to add clay inside the nose to adjust the balance.

So once everything else is put together, I put the nose on with a little piece of tape check that it balances about where I want it to, then take it out side and throw it to see how it does.

If it has too much nose weight it will smoothly nose dive and crash. Make sure your test flights are on soft grass or something so you don't wreck your glider when it does things like that.

If it has too little nose weight it will either try to pitch straight up and then stall suddenly pitching nose down again, or it will be so unstable it will flop around kind of randomly.

Keep messing with the nose weight until when you toss it forward it glides OK.

Then you glue the nose on, launch it and hope it works.

Note that the space shuttle isn't a particularly good glider, it will never fly really well compared to something that looks more like a traditional sailplane. But ya do what ya can.

 

[Ronz Rocketz]

"Exploring planet Earth..."

 

[Jeff Lassahn]

Orion Starfighter Mk II.

Still kind of rough, but I wanted to get some initial ideas committed to tangible form.
I think these are fundamentally more reliant on good decals for looks than the Torellian ships are.

 

[Jeff Lassahn]

Fancy forward air intake (Vacuum intake??? Ether scoop??? The physics of this universe is pretty sketchy)
Cool, or too much?

 

[neil_w]

I like it. Reminiscent of a plasma core but the fact that it’s a transition gives it a unique spin. Painting will be fun.

 

[mbeels]

Orion Starfighter Mk II.

I like it as well. At first glance it reminded me of the Estes Space Racer, but fancier. I like the forward scoop, it repeats a design element from the rear of the rocket and really helps tie it all together.

 

[jqavins]

Ether scoop???

 

[ReynoldsSlumber]

you could build a sky blue boom and stick a heavy scale or super scale shuttle craft or a Tholian Webb ship at the front.

Sounds like a formula for re-creating the very first scene in the original Star Wars movie, with the Rebel Alliance cruiser being chased by the ginormous Star Destroyer. You could even connect the two with "laser blasts."