Modular Fuel System Continued v3.3 (OBSOLETE)

[Shad0wCatcher]

@Tomato just a config error between tanktypes.cfgs. Delete the spherical-toroidal config in the modular fuels folder; the spherical pack already includes a config that's in-line with MFS capacities.

[foamyesque]

HoneyFox: I think I've fixed your null (although I hadn't encountered it myself, I think I see where...)

MFT v4 pre10: https://www.dropbox.com/s/ch8sw3iqtzv9dt7/ModularFuelTanks_v4_pre10.zip

OR

RF v4 pre10: https://www.dropbox.com/s/g49soc45iraz5ji/RealFuels_v4_pre10.zip

unchanged since pre9:

RO: https://www.dropbox.com/s/yt5f90v47cqpwfx/RealismOverhaul_v3pre2.zip

Note that in RF/RO engine throttles are limited (by type, techlevel, and the individual engine). Some can't throttle at all, some can throttle deeply; most U and L don't get any throttling until TL4 or so. As before, note that stock RCS is (a) modular and ( defaults to hydrazine, which is *not* ALL_VESSEL.

Link to stretchy pre for use with these: https://www.dropbox.com/s/rcemfqzq1ci4tnw/StretchySRB_v8pre1.zip

=======

Regarding throttling. Yes, working as designed. Note the "some can't throttle at all" part.

When you're configuring an engine (on the action editor screen), do note what it says min throttle is.

Deredere: Yes, you can. Although if you're using RF, you already have altered things pretty severely (mass ratios have changed a lot). RF really only makes sense if you're playing on Real Solar System or with KIDS, IMO.

RO does three main things:

1. Includes a set of engine configs

2. Makes solar panels, batteries, RTGs, reaction wheels, and so forth have realistic stats

3. Rescales parts and adds new parts that are rescales.

All the engines in the RF link here appear to be locked into the vanilla fuel/oxidizer combination.

EDIT: Screenshot.

No engine config menu is appearing.

Edited December 29, 2013 by foamyesque

[NathanKell]

You need a set of engine configs. Either use the "stock" engine configs from MFS3.3, or the RftS ones from Realism Overhaul (hence why I post that link along with RF, above), or SFJackBauer's RealEngines pack (available near the end of the RO thread).

[NathanKell]

Ferram: Home, now I can investigate.

Regarding SRB nozzles. Not quite sure I understand what you're asking for, since if you're radially attaching your boosters there _won't_ be anything under them...right?

Wanting equal throats makes sense though. How about I just use up another key so you can procedurally tweak the nozzle?

jrandom, re: multiple RCS fuel groups. I will try that out, sounds weird.

[jrandom]

jrandom, re: multiple RCS fuel groups. I will try that out, sounds weird.

It also might have been due to the new flow rules regarding RCS fuel. Sorry for all my non-bug bugs, I'm dealing with about a zillion things at once and it's taxing all four of my brain cells.

[ferram4]

@NathanKell: Little more info on the problem craft:

Upper stage vac-SRM behaves properly if the lower stage vac-SRBs are removed; once the lower stage vac-SRBs are added it picks up their characteristics. Although I didn't test, I'm tempted to see what happens if you stage the upper stage SRM before the lower stage SRBs to see if the lower stage SRBs pick up the upper stage SRM characteristics.

What I meant re: nozzles was that there's a logical reason to constrain the size of the nozzle for upper stage motors, say for fitting the nozzle into an interstage; I probably wasn't clear enough. As for controlling the nozzle size, why not just set the nozzle throat area to be proportional to thrust? Then, limit the nozzle size so that the throat can't be bigger than the ~50% of the rocket's width. Then nozzle size makes sense and you add a nice constraint to burn time that keeps solids as rocket motors and not mortars.

I would like to be able to cant the nozzles, but that's another thing entirely. Too many boosters have torqued themselves into the main tank due to excessive forces for my liking.

[NathanKell]

jrandom: Ah. Hmm, can you verify? I'll try as well.

Ferram: Found it. It's the perpetual bane of my .23 existence: the fact that for some reason modules do an OnLoad() _after_ OnStart. The MEC config is changed in OnStart, but only the local copy, not the confignode OnLoad() loads from. I added an OnInitialize to the Stretchy module to change thrust again (which runs after that weird second OnLoad()), and it works fine. I'll release it as v8, since so far no one else has found serious issues with Stretchy under .23 AFAIK.

Oh, I see. I really like the proportional-to-thrust idea. Actually, I'll run it in reverse (as I think you intended, re: your quip about mortars): limit available burn time based on max possible throat width. One thing, though--how to handle ullage/separation motors? They have a tiny burn time but the throat isn't that big, in relative terms, right?

[ferram4]

@NathanKell: I did manage to cause another a weird bug with the problem craft I sent you, which I think is caused by stretchy tanks.

The "Delta K" like stage has 6 stretchy tanks clipped into the procedural fairing bases at the top of the stage, with fuel lines coming out of them to ensure fuel crossfeeding.

Launch the rocket; revert to launch; launch again.

Partway through the flight (I think at ~the unloading distance from the pad) all of the symmetry counterparts of the aforementioned stretchy tanks will teleport to some distance below the rocket; the original will remain there. Fuel lines stretch to infinity in either direction when you do that, which is kind of weird.

As for the ullage motors, they're about the same as other SRM nozzle throats, but considering that the nozzle is generally hidden inside the aerodynamic fairing, most people don't notice it. See example. Generally it shouldn't be a problem since ullage motors are generally wider than they are long.

[jrandom]

jrandom: Ah. Hmm, can you verify? I'll try as well.

Must have been a fuel-feed problem. In this test rocket both the hydrazine (upper) and monopropellant (lower) RCS thrusters fire simultaneously:

[NathanKell]

jrandom: whew. :]

Ferram: 1. Will check. Sounds funky!

2. Ah, ok. (Side note: I thought S-IVB had pressure-fed hypergolic ullage motors?)

[ferram4]

@NathanKell: Yeah, that sounds right for the S-IVB. I dunno. If you want a better idea, you can look at Alliant Techsystem's Motor Catalog (PDF Warning). The STAR series includes some ullage and separation motors (STAR 5C, STAR 5CB, STAR F) that you can look at.

[ZacAttack42]

Any reason the SRBs in this mod burn for only ~15 seconds?

[Starwaster]

It also might have been due to the new flow rules regarding RCS fuel. Sorry for all my non-bug bugs, I'm dealing with about a zillion things at once and it's taxing all four of my brain cells.

Damn, sounds like you got the upgrade. I'm still operating on two.

[NathanKell]

Ferram: cool find!

ZacAttack42: Did you download Realism Overhaul prerelease, as I suggested? Sounds like no.

[ZacAttack42]

NathanKell: Yes I tried it but I didn't really want to play with it because it messes up so many things' sizes and leaves me with a bunch of puny, underpowered engines.

I just want to play with Real Solar System, and with tanks and engines with performance and masses more like real life. (Its hard to do anything with RSS and stock KSP part stats.)

I don't suppose there's any combination of mods that can do that is there?

[NathanKell]

Ferram: Confirmed. Holy smokes that's weird. No idea what's causing it, either, and the log doesn't provide anything. I'll ponder and play for a while, but...yikes it's a weird one.

[AbeS]

ZacAttack42 they are not really puny and underpowered, there are all kind of engines. Have you seen how huge some of the KW and NP engines get? The good combination is SSRBs, MFS and RO (DR and FAR too obviously)

[amo28]

Nathan: Any chance you have any interest in pre-releasing your current MFS calculations spreadsheet for V4? I know it's still a pre-release itself, but I'd love to have the new fuel types to play around with. Can't play without the Kosmos engines.

[NathanKell]

Sure.

https://www.dropbox.com/s/dseuvm4f6m8v4no/Calcs.xls

It's always at that link, so keep it around and check it for updates.

Finally has updated docs.

Note that it's set for RftSEngines because that's what I play with, and only the engines I actually use are filled in. Yeah, well...

[NathanKell]

RF and MFT are both up. Consider this thread over and done.

RF: http://forum.kerbalspaceprogram.com/threads/64118

MFT: http://forum.kerbalspaceprogram.com/threads/64117

Edited December 30, 2013 by NathanKell

[Buddy431]

@NathanKell: I did manage to cause another a weird bug with the problem craft I sent you, which I think is caused by stretchy tanks.

The "Delta K" like stage has 6 stretchy tanks clipped into the procedural fairing bases at the top of the stage, with fuel lines coming out of them to ensure fuel crossfeeding.

Launch the rocket; revert to launch; launch again.

Partway through the flight (I think at ~the unloading distance from the pad) all of the symmetry counterparts of the aforementioned stretchy tanks will teleport to some distance below the rocket; the original will remain there. Fuel lines stretch to infinity in either direction when you do that, which is kind of weird.

As for the ullage motors, they're about the same as other SRM nozzle throats, but considering that the nozzle is generally hidden inside the aerodynamic fairing, most people don't notice it. See example. Generally it shouldn't be a problem since ullage motors are generally wider than they are long.

Ferram,

I don't think it's stretchy tanks. I had the same problem with a Mun lander using (I think) only stock parts + mechjeb. It's interesting, because I'd already landed the Mun lander once and taken off again to a new site, and done this with the same design before with no problem. Happens exactly as you describe: get a certain distance from where I was parked (about 3 km I think?), and I get the three symmetry attached tanks teleporting back, and fuel lines stretching.

I'm landed near the south pole of the Mun, and the flags I try to plant are also showing weird behavior: I can plant them, and they look fine, but if I quickload the flag isn't visible (it is in the map view), and it claims it's under acceleration if I try to switch away. It's happened every time I've tried it with this specific craft, but I've used identical craft before in different areas with no problem.