NathanKell

[1.2] Real Solar System v12.0 Dec 8

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Could anyone give me a hint what amount of delta-v would be reasonable for a proper circularization at the end of the ascent?

I'm still playing aroung and don't know if I'm getting it right. Right now my first stage burns out at around 150km with an Apoapsis of 320km. I then start circularizing around two minutes before Apoapsis (w/ Mechjeb) but it needs nearly 3000m/s delta-v (second stage is big enough for that). Is that a decent amount or is my ascent too steep? I already got reentry effects on my ascent (TWR 1.4 on takeoff, 4800 delta-v, 1000 ms/s at 40°, 1500m/s at 38000m).

Thank you!

I don't coast to apoapsis at all, I just gradually turn the craft and burn straight into orbit. So it sounds like your ascent is too steep.

If you're getting reentry effects then your upper stage must be very light in relation to your total rocket mass. Consider a smaller first stage and a larger second stage or throttle back the main engine when fuel gets low.

Numbers sound okay though, 3km/s is about what I'd expect for circularization if you launch as you described.

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I don't coast to apoapsis at all, I just gradually turn the craft and burn straight into orbit. So it sounds like your ascent is too steep.

If you're getting reentry effects then your upper stage must be very light in relation to your total rocket mass. Consider a smaller first stage and a larger second stage or throttle back the main engine when fuel gets low.

Numbers sound okay though, 3km/s is about what I'd expect for circularization if you launch as you described.

Thank you! I guess I will then play around with the stages.

Another question I didn't find enough sources to: How do you set up your COMsat network? Is it in RSS also possible to have a 3 Sats Omni network for LEO communication? Or are the omni antennas not strong enough? What orbit heights do you use?

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I'm not sure what the ranges are with RO, but you can use this formula for finding the distance between them:

2*sin(180/n)*(a+r) where

n= number of sats

a= altitude

r= radius

This is in degrees, not radians so remember to switch to degrees if you use wolfram alpha.

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shrx: Bodies without an existing atmosphere won't have an AtmosphereFromGround created for them. Kopernicus will do that, I think, if not now, soon.

Regarding the temperatureCurve: not sure why it's not loading. I'll check.

Thanks. I'm not really concerned by the visuals, just the physical effects.

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Could anyone give me a hint what amount of delta-v would be reasonable for a proper circularization at the end of the ascent?

Depends on what mod setup you are running, and what your aim is. Assuming you are using the realism-enhancing mods and aim to simply get into LEO, then the answer is: you shouldn't have a "circularization burn", because generally there should be only a few seconds of "coasting" between first stage burnout and second stage ignition on a properly designed and piloted rocket. There are exceptions, such as getting into GEO, or using mismatched hardware for cost-cutting purposes (like the ICBM-derived rockets of the 1950s) but generally the rocket should be under near-constant thrust from liftoff until target orbit is achieved. TWR 1.4 on takeoff is high, if you mean sea-level TWR; personally I usually aim for a TWR of 1.2 on takeoff, that provides just about perfect amount of acceleration to avoid exceeding terminal velocity.

Edited by Hattivat
inserting quote for clarity

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Thank you! I guess I will then play around with the stages.

Another question I didn't find enough sources to: How do you set up your COMsat network? Is it in RSS also possible to have a 3 Sats Omni network for LEO communication? Or are the omni antennas not strong enough? What orbit heights do you use?

Math time:

dDShPe8.png

S1<-->O represents the minimum height for a 3 sat network. S2<-->O represents the maximum height. S1 is limited by the radius of the planet (Any lower and it wont see the next sat over the horizon), S2 is limited by the range of your antenna.

Basic geometry tells us that S1<-->O = O<-->A/cos(60°) = 2*O<-->A. So your satellite must be at least twice the radius of the planet up. KSP deducts the radius of the planet in height measurements, so if you orbit earth with a radius of 6.4Mm you must at least orbit at 6.4Mm or higher.

Our satellites upper range is when it no longer has the range to contact the next sat. This happens when S2<-->B is half the antenna range. More basic geometry shows that S2<-->O = S2<-->B / sin(60°) = S2<-->B/(0.5*sqrt(3))

S2<-->B is half of our antenna range. Lets name that r. So our upper orbit is bound by r/sqrt(3). Substract the radius of the planet to get the height in the units ksp uses. So in summary:

Minimum height = radius planet.

Maximum height = (antenna range/sqrt(3)) - radius planet

Anything between those 2 values can be used as orbit for your comsat network. I strongly suggest you multiply all antenna ranges for RemoteTech by a factor of 10 (look for settings.cfg in the RT folder). Else you won't be able to build a 3 sat network around Kerbin.

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I'm not sure what the ranges are with RO, but you can use this formula for finding the distance between them:

2*sin(180/n)*(a+r) where

n= number of sats

a= altitude

r= radius

This is in degrees, not radians so remember to switch to degrees if you use wolfram alpha.

Thank you!

I wasn't able to figure out how to convert within WolframAlpha but another search got me these two handy tools:

http://rechneronline.de/pi/equilateral-triangle.php

https://docs.google.com/spreadsheet/ccc?key=0AkXf-77s6gmFdEdVeGFqX0xobTczYkhEaEVrVTdWV3c&usp=sharing#gid=1 (from this thread)

Hattivat: Thank you for this information. Guess I'll have to tweak my rocket a bit more. Or my ascent and gravity curve. Has anyone seen a good video of one?

Ralathon: Thanks for your detailed explanation! Realism Overhaul already multiplies the antenna ranges but the omni one (the longest range one has 10Mm) won't be able to see each other if I don't use at least five. That's why I will go for an orbit of around 8000 orbit and use dishes.

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Has anyone seen a good video of one?

It's surprisingly hard to find a video of someone experienced doing it (most youtube videos are either of people obviously just starting to play in RSS/RO or skip the "boring" parts, which includes most of the launch sequence). I've managed to find a decent example though, here you go:

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shrx: Bodies without an existing atmosphere won't have an AtmosphereFromGround created for them. Kopernicus will do that, I think, if not now, soon.

Regarding the temperatureCurve: not sure why it's not loading. I'll check.

Might it be because it didn't have an atmosphere? Or are they mutually exclusive?

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In all this, I accidentally overwrote my only copy of 7.0. Do you have the v7.0 dll file backed up anywhere?

Any chance of this, Nate?

EDIT: Nevermind, I installed v6.2 and swapped the old dll for your most recent one and everything works. I don't even understand. Maybe this was an issue with the other two folders that came with v7.1?

Edited by hydropos

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I haven't found any mention of this, but it kind of a game breaking issue to me. There are clearly visible "tiles" all over Kerbin, and some of them are actually missing. I am currently using 2048 because the 4096 is five times worse in this aspect. Did I do something wrong? Is it normal?wEhrO2I.png

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I'm in .24.2, and this behavior is very odd, considering it was working just fine in .24. I'm using the stock config and the 2048 texture pack. I have redownloaded RSS but the problem still prevails. Eeloo and Dres are their stock colors and at their stock distances, and all the moons of Jupiter (except one) are inside of it. Also, Minmus is at its stock distance from Earth.

EDIT: I downloaded and installed the PlanetFactory config and it seems to resolve this, must be the 'stock' config.

I'm having this same problem. What's the problem with the default RSS config that makes it do this? Should I try a different texture pack? I'm using the 2048.

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Hi,

I can't figure out, what I need to do to get a 10x kerbol system. Do I only have to download the RSS plugin, copy it to gamedata, then download the config and put it into the rrs folder in gamedate?

I'd appreciate some help,

thx

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Hi,

I can't figure out, what I need to do to get a 10x kerbol system. Do I only have to download the RSS plugin, copy it to gamedata, then download the config and put it into the rrs folder in gamedate?

I'd appreciate some help,

thx

If you just do that, you'll get a system that is earth-like (in regards to what is where), but still uses the same kerbal planets/moons. To get a 10x kerbal system, you need to replace the RealSolarSystem.cfg file with the one JSimmons made.

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If you just do that, you'll get a system that is earth-like (in regards to what is where), but still uses the same kerbal planets/moons. To get a 10x kerbal system, you need to replace the RealSolarSystem.cfg file with the one JSimmons made.

Hi,

thx. I'm doing excately that, but it doesn't have any effect. What I did not, is using the rss textures. Do I also have to use the rss textures, even though I want a resized kerbol system?

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This is general question to all RSS-Mechjeb users, what can I do to stop Mechjeb making my rockets jump all over the shop with the ExsurgentEngineering plugin?

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mecki: Right now there is no way to change RT2 settings except by physically replacing the settings file (and incidentally overwriting user settings). The RT2 devs had said they were going to change to a method that allows MM patching; when that happens I'll happily use it.

As for circularization: as others have said, the proper amount is 0. :D (Unless you have very high thrust upper stages, like solids.) I will just say, though, that TWR 1.4 at takeoff isn't that far out of line; Zenit (IIRC) is about 1.5, in part due to its ancestry as a booster for Energia, but also in part because the Russians have always used higher TWRs than US launch vehicles.

Preliator: I see no reason it wouldn't be.

AndreyATGB: Pretty sure any and every body has a temperatureCurve...but it's been a while since I checked and maybe it's something silly like "if using legacy atmosphere, temperature = pressure * 20". Wouldn't necessarily surprise me.

hydropos: missed your post, sorry. Note that for *all* my mods, prior versions are always available from the releases page. The download link links directly to the current release on GitHub, but if you click the GitHub link, then Releases, you will see all releases.

Clythoris: if you go into VAB/SPH/Tracking and then back out again, they should disappear. If not, I need a brighter screenshot.

Friedrich Nietzsche: Yes, that's correct: download latest RSS, replace existing cfg with the new cfg. What do you mean by it not having any effect? You should not use the textures.

Captain Party: Exsurgent Engineering is no longer used by the current (from GitHub) build of RftS. It's gone back to the stock gimbal. r4m0n is currently tweaking MJ to behave better with the stock gimbal.

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Has anyone upgraded the 6.4x Kerbin config to the new RSS? Regex's (now locked) thread said he wasn't going to be able to update, and I'm still using RSS v6 since his config doesn't work on v7. Would be nice to use the proper version of RSS. :)

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Wanna volunteer? :P

It shouldn't actually take much work--what do you mean by "doesn't work on v7"?

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Wanna volunteer? :P

It shouldn't actually take much work--what do you mean by "doesn't work on v7"?

Why did I know you'd ask that. :wink: Was already planning on it if no one else had.

Last time I checked, the config simply didn't get loaded properly, and the logs (link) seemed to imply something off with the AtmosphereFromGround and the LaunchSites.cfg. The former one may have been fixed in 7.1, but I haven't tried it since. It was also during the .24.x switchover so other un-updated mods may have been playing spoiler.

If you see anything important in the logs, let me know. Otherwise, I think I have a project for this weekend.

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In the end of your log, it says a bunch of things couldn't be loaded. Dunno if that's important, since I don't mess around with logs much

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In the end of your log, it says a bunch of things couldn't be loaded. Dunno if that's important, since I don't mess around with logs much

Every log has that (for me anyway) whether it's running well or not. I think those have to do with the shutdown procedure of the program, but I figure if I'm not noticing anything wrong I'm not going to hunt for problems. :wink:

Alas, it seems the 6.4x config is less broken than before. The resizing works properly at this point, but the launch sites don't get loaded in. Which is pretty much all the log says on that note. I'll see if I can make it work properly. If I do get it rolling, I'll probably make a new thread and post that link here for reference.

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AndreyATGB: Pretty sure any and every body has a temperatureCurve...but it's been a while since I checked and maybe it's something silly like "if using legacy atmosphere, temperature = pressure * 20". Wouldn't necessarily surprise me.

Pretty sure it's not atmosphere dependent at all... it's been awhile since I poked at those parts but I do seem to recall that they were separate.

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Clythoris: if you go into VAB/SPH/Tracking and then back out again, they should disappear. If not, I need a brighter screenshot.

Thank you.

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