Attaching Fuel Tanks With Engines

[JuggernautOfWar]

You may attach Solid Rocket Boosters to radial decouplers. It makes sense to also attach a liquid fuel tank/engine to a radial decoupler. Why can't we? Is this unrealistic? I'm pretty sure I've seen radial liquid fuel cells before on rocket craft.

Attached is an example of what I'm talking about.

[Jarnis]

...but you can add liquids below solids. So a ring of solids midway up the core stage, then decouplers under them and some liquid fuel tanks + engines below them.

Not very stable, can rip itself apart, handle with care. Recommended for use only with Kerbals that have submitted a last will & testament on record.

Still, the simplest construct I have placed on stable orbit consists of a parachute-module-decoupler-liquid tank-liquid-engine 'upper stage' connected to a lower stage with SAS, four fuel tanks and a tri-module with three engines in the bottom spiced with a ring of six solid rocket boosters around the middle of the rocket. Solids give you the oomph to get the whole thing moving and the single 'main stage' with three liquid engines and four fuel tanks gets you to ~30km at which point the light upper stage will get you the needed horizontal velocity with a little bit of fuel to spare for deorbit. Margins are very tight.

Getting more than that to a stable orbit requires three-stage designs with somewhat convoluted first stages (due to the massive takeoff mass)

[reissdorf]

I was a bit annoyed of not beeing able to attach them, too. So I edited the config.

Just open the part.cfg in *\Parts\fuelTank\ with notepad and add

node_attach = 0.0, 0.0, -5, 0.0, 0.0, 1.0, 1

under node definitions and change the attachment rules to

attachRules = 1,1,1,1,0

Hope that helps

[JuggernautOfWar]

I was a bit annoyed of not beeing able to attach them, too. So I edited the config.

Just open the part.cfg in *\Parts\fuelTank\ with notepad and add

node_attach = 0.0, 0.0, -5, 0.0, 0.0, 1.0, 1

under node definitions and change the attachment rules to

attachRules = 1,1,1,1,0

Hope that helps

Oh thank you, that will surely come in handy. I wish this bug didn't exist though. I wonder if the devs will read this?

[feldopropane]

Oh thank you, that will surely come in handy. I wish this bug didn't exist though. I wonder if the devs will read this?

they probably will the devs are real active on the forum

[JuggernautOfWar]

After more tinkering it seems the ONLY use for the radials are attaching more SRBs. It doesn't appear to allow any other type of module other than the booster. What use do these really even have? SRBs are pretty much only useful for initial liftoff and getting through the denser atmosphere. Once you hit less gravity, friction, etc, liquids are really the only way to go.

[guerilla_gearhead]

It's useful for getting rid of whatever you attached, hence radial decoupler. Sure, you can only attach SRB's right now but say you have them hooked radially to a bunch of liquid tanks, they liquids burn much longer so once your SRBs burn out you want dump them to lose the extra weight.

[JuggernautOfWar]

Yeah I know. The whole point of this thread is to figure out why we can attach SRBs to decouplers but not Engines.

[reissdorf]

It's probably because the code isn't ready yet. I got some quite nice results using my fix, but sometimes it just laggs like hell.

I'm not sure if it's collison detection because the node properties are not correct (just copied from the SRB), or if it's the code that distributes the fuel (it seems to happen sometimes when a center fuel tank without an engine is fueling the engines of the tanks attached to it, if a design shows that error it's reproducable).

But there are some nice designs you can make.