Ukranian R-360 Neptune

[BigMacDaddy]

For folks not in the Facebook Estes or OpenRocket groups...

Someone shared some photos of the Ukrainian R-360 over in the Estes group and it looked like a pretty cool rocket.



I first modeled in OR to see how hard it would be to make this stable with those large forward-positioned fins and smaller rear fins on the sustainer. I went with a two-stage model with a BT-60 main tube and BT-80 booster portion (BT-80 is 5-10% too large but rather make that compromise than have to scratch build). Note: Russian version has a smaller booster (maybe BT-55).

Looks like it should be stable with 2.5oz in nose. I put a D12-0 + D12-5 and seems like 390m or so although obviously need to weigh the final build. C11 or even C6-5 would probably help reduce the nose weight needed.




I took a 1st crack at designing the main 3D printed components so I can make BT-60/BT-80 body tubes and plywood fins... lots more details to add and work to do.



p.s., I am looking for someone with a 3D printer and great finishing skills that can print and build some of my models, build / finish them, give me feedback on assembly/design, and send me a picture of the finished model.

 

[cls]

Omg! Great minds think alike. Just this evening I was researching Neptun. It's a handsome thing. Reminds me of my BT80 upscale Quest AGM84 Harpoon.

I would build it static, without the launch tube and rotating fins.

A worthy project

 

[ThirstyBarbarian]

That’s a cool project. When you are done building that, you could build the companion model by Revell.

 

[BigMacDaddy]

Omg! Great minds think alike. Just this evening I was researching Neptun. It's a handsome thing. Reminds me of my BT80 upscale Quest AGM84 Harpoon.

I would build it static, without the launch tube and rotating fins.

A worthy project

Yeah, I had not even thought about doing the folding fin design (although that would be an interesting challenge for someone into tube launches)... Right now I am working on how the booster and sustainer will connect and deciding how many details I should add -- things like the pods on the body, fin root details, details on transitions, those booster fin attachment bars, shroud details, etc...

 

[StreuB1]

That’s a cool project. When you are done building that, you could build the companion model by Revell.

View attachment 514633

Looks like another great offering from Revell!! I really enjoyed their Ukrainian farmer models as well. One box, two models, and a tow strap!

 

[shockie]

 

[Brainlord Mesomorph]

Dudes, I am so working on this.

Can you (did you) post that OR file? it'll save me a lot of time.

 

[BigMacDaddy]

Dudes, I am so working on this.

Can you (did you) post that OR file? it'll save me a lot of time.

Here is the Open Rocket ORK file.

 

[Hobie1dog]

Love the big forward fins, keep us posted on the build process with pictures.

 

[aerostadt]

Here is the Open Rocket ORK file.

Nice looking Open Rocket file! Has the 2-stage version flown?

 

[BigMacDaddy]

Nice looking Open Rocket file! Has the 2-stage version flown?

In real life yes, in my model life I am 3D printing the first set of prototype parts...

 

[Rob Caswell]

Here's a few more pics, if anyone's looking to model the subject. Jim Flis said he's working on a two-stage version he hopes to fly this weekend.

 

[jqavins]

I see in the fourth picture above that it's an anti-ship cruise missile. Anyone know if that's what sank the Moskva?

No, no Commrade, Moskva, as reward for her great service to USSR Mother Russia, was promoted to rank of Submarine.​

 

[BigMacDaddy]

I see in the fourth picture above that it's an anti-ship cruise missile. Anyone know if that's what sank the Moskva?

No, no Commrade, Moskva, as reward for her great service to USSR Mother Russia, was promoted to rank of Submarine.​

Someone was saying that this was the missile that sank that ship but others were arguing that it was just an explosion / fire that sank it. I have not been watching the news...

 

[Rob Caswell]

Someone was saying that this was the missile that sank that ship but others were arguing that it was just an explosion / fire that sank it. I have not been watching the news...

"Others" would be the Putin-blessed Russian press.

It's telling that, after the Moskva sank, the Russian carried out a renewed, retaliatory strike against Kyiv. It doesn't make sense to punish Ukraine because you sunk your own boat.

 

[jqavins]

Someone was saying that this was the missile that sank that ship but others were arguing that it was just an explosion / fire that sank it. I have not been watching the news...

Yeah, well it's mainly the Russian propaganda machine saying it was a fire. And if it was a fire that reached the munitions store causing an explosion (and if said fire was not in turn caused by a couple of Ukrainian missiles) then it would be indicative of terrible ship design and/or an incompetent crew.

The US DoD, the last I heard, said that they can't positively confirm it was missiles. But it was missiles.

My question was only was it this missile.

"Others" would be the Putin-blessed Russian press.

Ninjad.

 

[Rob Caswell]

Almost certainly. This is Ukraine's home-grown antiship missile that has just entered service.

 

[BigMacDaddy]

1st set of 3D printed prototype parts on the way...

 

[shockie]

I think this should be built with folding fins and launched from its cannister. Now that would be way cool.

 

[BigMacDaddy]

I will have to do the fins tomorrow -- too late to start up the CNC... May shorten the coupler insert between stages (worried it might catch).

 

[Alan15578]

Nice looking model.

I was wondering how the Neptune compares to the US Harpoon. Does the Neptune do sea skimming?

It seems impressive to sink such a large vessel with only two missiles. Large ships have many sealed compartments and to sink one you have to puncture and flood a lot of compartments. Did they just get lucky and hit the ammo magazine?

 

[rharshberger]

Nice looking model.

I was wondering how the Neptune compares to the US Harpoon. Does the Neptune do sea skimming?

It seems impressive to sink such a large vessel with only two missiles. Large ships have many sealed compartments and to sink one you have to puncture and flood a lot of compartments. Did they just get lucky and hit the ammo magazine?

While subdivided, modern warships are nowhere near as heavily armored as the old versions were, and modern missles have much more powerful warheads or at least more powerful explosives.

 

[Sooner Boomer]

Looks like it should be stable with 2.5oz in nose

I don't think you understand how heavy 2 1/2 ounces is. You need that much to keep the Cg/Cp relationship correct due to the forward fins, but that's a *lot* of nose weight for a model rocket.

 

[OzHybrid]

I will have to do the fins tomorrow -- too late to start up the CNC... May shorten the coupler insert between stages (worried it might catch).

View attachment 514864
View attachment 514865 View attachment 514866

The actual photos of the missile seem to show the booster as a slightly smaller diameter than the simmed one is that photo of the Russian version? Other than that, top job...... Gotta love 3d printing.

 

[cls]

It's telling that, after the Moskva sank, the Russian carried out a renewed, retaliatory strike against Kyiv. It doesn't make sense to punish Ukraine because you sunk your own boat.

self sunk the flagship of the navy... during a land war... ok.

 

[cwbullet]

I will have to do the fins tomorrow -- too late to start up the CNC... May shorten the coupler insert between stages (worried it might catch).

View attachment 514864
View attachment 514865 View attachment 514866

You could 3D print the fins with ASA or PC Blend.

 

[BigMacDaddy]

The actual photos of the missile seem to show the booster as a slightly smaller diameter than the simmed one is that photo of the Russian version? Other than that, top job...... Gotta love 3d printing.

Yes, as far as I can tell the Russian version has a thinner booster but then I also find some pictures of the missile that seem to be labeled R-360 also with the thinner booster. I wonder if there are higher and lower capacity booster options or different fuel types of something (or iterations in the development over last few years).

"The Ukrainian missile is generally similar to the Kh-35U, but has a longer body with more fuel, larger booster, and some other modifications." - http://www.military-today.com/missiles/neptun.htm

I thought that a couple of pictures showed the larger booster as well as the 3D rendering (but sometimes hard to tell what is CGI these days). Once I decided on the BT-60 for the main body I was kinda locked into BT-80 for booster if I wanted to use what was on hand.



Someone posted that they had found that online that the booster was .6m in diameter (while the main body is .4m). 4:6 would be close to the ratio of a BT-60 to BT-80 tube which is 41.6 : 65.7 (BT-80 is around 5-10% larger than it should be). Only hard data I can find is that the launch tube is .6m in diameter (so booster would be a little smaller I assume) - according to Wikipedia.

 

[BigMacDaddy]

I don't think you understand how heavy 2 1/2 ounces is. You need that much to keep the Cg/Cp relationship correct due to the forward fins, but that's a *lot* of nose weight for a model rocket.

I have had a bunch of rockets with 2-3oz in nose to stabilize them (I use 2 and 3oz fishing weights or sometimes a nose-full of pennies). The challenge becomes getting a big enough chute in there so it comes down at a reasonable speed. I don't love putting that much weight in the nose but it is sometimes necessary to make a missile that has active guidance in the real world stable with just BP rocket engines (particularly give the weight of the 3D printed parts near the rear of rocket). That is why I put 24mm motor mounts in here.

 

[neil_w]

Looking good. Ya gotta paint this one, it's just a simple one-color paint job.

 

[BigMacDaddy]

Looking good. Ya gotta paint this one, it's just a simple one-color paint job.

Thanks -- And I do have orange spray paint...