The Versatility Marathon Challenge

[KinkyFerrets]

So I'd like to submit a Core Vehicle

Mods: MechJeb, RasterPropMonitor, and while no parts on, KAS is installed.

[700NitroXpress]

So I'd like to submit a Core Vehicle

Alright, looks good. Take it through the shakedown run around the moon and back and then you're good to go for missions.

[700NitroXpress]

Hi, first post here as I've decided to give this challenge a try. I'm currently in the design phase for the core vessel and had a question regarding a mod-related engine. Is the large nuclear engine from the KSPX considered balanced enough? It seems just about at the same balance as the smaller stock nuke, with a smidge more thrust to the weight. If not, I'll probably design around smaller engine clusters then.

Specs:

Stock - 2.25 tons for 60 thrust at 800 ISP in vacuum

KSPX Large Nuke - 5.0 tons for 150 thrust at 800 ISP in vacuum

Yeah, I prefer it if people use the stock nuke engine. If you do use the mod engine then the specs would have to be modded to be the same. Especially sense that engine is the standard for basically all core ships.

[700NitroXpress]

Well done on that mission 4 Finwen, that platform would make me a little nervous, but it looks like it worked out without much trouble. Good designs overall and nicely done.

[Finwen]

Yepp the plattform made me nervous too. The challenge of bringing home a flawed design is fun too. But i will not use that design again

[Quiana]

Yeah, I prefer it if people use the stock nuke engine. If you do use the mod engine then the specs would have to be modded to be the same. Especially sense that engine is the standard for basically all core ships.

That's fine. It's in essence two of the stock nukes but modeled up to the 2.5 mount. I'll just add some part count and cluster the stock nukes (probably get a smidge more thrust by clustering in a trio that way).

Once I get home from work I'll finalize my design and provide specifications as well as the initial 'burn in' mun run.

As for mods I have in use that would impact the vessel or increase the challenge: Deadly Reentry, TAC Life Support, FAR, Surface Mounted Lights (they're pretty), RealChute, KAS, and Engineer Redux for displays.

I figured I'd get those listed now in case you had any concerns or comments about their viability. I will be more than happy to remove/change any mods as necessary to be in the spirit of the challenge, though as you can see I do enjoy making things more difficult on myself with DRE and TAC.

[Hodo]

Yeah, I prefer it if people use the stock nuke engine. If you do use the mod engine then the specs would have to be modded to be the same. Especially sense that engine is the standard for basically all core ships.

The KSPX nuke engine is fine, it is basically a larger (2.5m) nuke engine. It weighs more than twice the amount of the standard engine, it creates only a bit more thrust for its size and has the same ISP. I think its TWR is identical to the standard 1.25m engine.

I use it because it cuts on parts counts and doesn't look ******ed when attached to the back of a craft.

[Quiana]

The KSPX nuke engine is fine, it is basically a larger (2.5m) nuke engine. It weighs more than twice the amount of the standard engine, it creates only a bit more thrust for its size and has the same ISP. I think its TWR is identical to the standard 1.25m engine.

I use it because it cuts on parts counts and doesn't look ******ed when attached to the back of a craft.

Yeah, I've been doing the math on perhaps balancing a nuclear reactor from the Near Future mod, as there are examples of real reactors sent into space. They weigh a lot, produce a fair bit of power, but require refueling on average within a year in space depending on reactor load. Though I feel it would be too frowned upon, so it'll likely be some Gigantor panels on a cluster. Not that the core module needs a lot of power production, it just helps to always have power available when necessary.

[700NitroXpress]

Quiana, the mods you have listed all look fine to me from what little I know about them. Increase the challenge at your own risk, the only thing that isn't allowed are parts or mods that would give an unfair advantage over stock players. The real question that I have about that nuke engine is if it uses the same fuel efficiency to travel the same distance as a regular nuke engine. Because it seems that because of the higher thrust, it would be able to travel further on less fuel. One of the current members of this challenge I believe is currently using it, just with equalized stats to the current stock nuke engine. So to keep it fair, I would have to maintain that ruling. I don't think it's that unbalanced, but it still seems a little better that stock.

[Quiana]

Okay. I'll be finishing the core craft tonight and hopefully submit it later. I've modified the engine down a touch (stock nukes are 26.6~ TWR while the KSPX one was 30 TWR) including modifying the electric output to match (12.5 down to 10). It is exactly the equivalent of two stock nukes now. It's going to be interesting to streamline and test it, as I have a few ideas how to narrow the profile down, but it essentially is a 'puller' type tug. Since it avoids stack compression for longer payloads, it's a lot easier (though time-consuming) to haul payloads around without breaking the whole affair. Plus, with the design, I can dock additional fuel on 'top' of the engines which actually assists in balancing the COM to stay relatively centered.

[700NitroXpress]

So something like this where you can stockpile a kiloton of fuel right next to the engine, only going horizontally instead of a vertical build?

[Hodo]

Quiana, the mods you have listed all look fine to me from what little I know about them. Increase the challenge at your own risk, the only thing that isn't allowed are parts or mods that would give an unfair advantage over stock players. The real question that I have about that nuke engine is if it uses the same fuel efficiency to travel the same distance as a regular nuke engine. Because it seems that because of the higher thrust, it would be able to travel further on less fuel. One of the current members of this challenge I believe is currently using it, just with equalized stats to the current stock nuke engine. So to keep it fair, I would have to maintain that ruling. I don't think it's that unbalanced, but it still seems a little better that stock.

It weighs more than stock. By a bit more.

5 tons vs 2.25 tons.

It generates slightly more power, 150kn vs 60kn

It has the exact same ISP 800.

It is slightly more powerful TWR than the stock nuke engine, but it is also larger, 2.5m vs 1.25m, and has a tenancy to overheat faster.

As for building outwards, that works fine and dandy when you run the horrible KSP aerodynamic model which was made by a mermaid who has never seen air.

[KinkyFerrets]

Ver-Mar Core

[700NitroXpress]

Ver-Mar Core

Alright looks good, you're approved for the first mission. Can you post a picture of the ship as well?

Hodo, this is building outwards in space where aerodynamics have no impact on the vessel, no air. Everything was launched up vertically.

[KinkyFerrets]

Alright looks good, you're approved for the first mission. Can you post a picture of the ship as well?

[Quiana]

So something like this where you can stockpile a kiloton of fuel right next to the engine, only going horizontally instead of a vertical build?

*SNIP IMAGE*

Somewhat. I didn't get to finish the design the other day but it will be complete tonight. The idea is a central stack with two engines as outriggers. Fuel can be added to the top of the outriggers, and they have side mounts for additional engine clusters (probably a good thing for mission 5) or other hardware. Then the central stack has a docking port going down, allowing it to mount a 'train' attachment behind it. This gives a handy way to balance the entire core with any attachments as I can ballast the payload if the fuel's heavier, or add more fuel if the payload is large.

EDIT: Since I don't want to double-post, here we go! Core craft completed and appropriately named "Tugtitus I" for the first of her kind.

Javascript is disabled. View full album

As for building outwards, that works fine and dandy when you run the horrible KSP aerodynamic model which was made by a mermaid who has never seen air.

I did indeed launch this thing with FAR. I had to put nosecones on the engine clusters to do so, but they worked fairly well and it was rather aerodynamic for an outrigger style.

Edited April 8, 2014 by Quiana
Added Core Craft IMGUR

[Finwen]

My ship is ready for Mission 5:

I will bring 3 rovers and a science lab and some extras....

[700NitroXpress]

Ok Quiana your ship looks good to go for missions.

Finwen that thing looks like it would wobble a lot. Good luck, as soon as mission 5 has been completed by someone, I'll release mission 6.

[Finwen]

Yes it did wobble some but i ended up using my nuke engines on core ship further ahead for more stability. Then it was allot more stable but i did only had 0.03 TWR so the transfer burn to Duna took about 2 hours real-time.....

[700NitroXpress]

Yes it did wobble some but i ended up using my nuke engines on core ship further ahead for more stability. Then it was allot more stable but i did only had 0.03 TWR so the transfer burn to Duna took about 2 hours real-time.....

Oh man... 2 hours, I feel your pain. Got enough fuel to get back?

[Finwen]

I think i have enough fuel and the mass on return mission will be allot less. Turning this long ship takes a long time to. A few minutes for a 180 degree turn for aerobraking now...

[700NitroXpress]

I think i have enough fuel and the mass on return mission will be allot less. Turning this long ship takes a long time to. A few minutes for a 180 degree turn for aerobraking now...

Yeah, it looks like you should have enough because of that extra large fuel tank in the middle. More than one of the orange jumbo's. You're right, should loose 50% or more mass from all of the rovers and things being dropped and that will really help the return burn. I'm still preparing for mission 3, I like Moho, but it takes a lot of fuel to get there and back. When I docked 9 large docking ports all at the same time, I didn't have a fuel gauge for some reason, so I'm rebuilding now.

[Finwen]

Good luck on mission 3. For me it was the hardest so far.

I did aerobraking at Duna and with a few minutes of additional burn i entered a highly elliptical Duna orbit. I did a higher aerobraking maneuver to circularize the orbit (during seveal orbits).

IKES!!! First aerobraking orbit did put my directly into Ike and it and i was about to crash into Duna after that....

With RCS i dived very deep into Duna atmosphere to avoid the influence of Ike and got down to periapsis under 200km. So now i am parked in a nice 70 * 178 km orbit around Duna. Time to land later this evening.

[Sensi]

Since last update, my core ship starts wobbling like crazy and disintegrates in less than 10 seconds. I've updated all mods but it doesn't solve the problem. Looks like I have to build a new one...

Edited April 7, 2014 by Sensi

[Quiana]

Since last update, my core ship starts wobbling like crazy and disintegrates in less than 10 seconds. I've updated all mods but it doesn't solve the problem. Looks like I have to build a new one...

Check some of the mods. If they have not updated the node changes (node attachment size) then yes, they will be VERY unstable. Not all mods that I know of with parts have fixed this just yet.