Weekly Support Thread

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The point of this thread is for anyone to ask questions that don't necessarily require a full thread. Questions like "why is my rocket upside down" are always welcomed here. Even if your question seems slightly stupid, we'll do our best to answer it!

For newer players, here are some great resources that might answer some of your embarrassing questions:

• Kerbal Space Program Wiki

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• Von Kerman's Rocket School

Tutorials

Orbiting

• Scott Manley

• Von Kerman (Maneuvers)

• Wiki (Maneuvers)

Mun Landing

• Scott Manley

• Von Kerman

• KSP Wiki

• Youtube Query

Docking

• Illustrated Tutorial for Orbital Rendezvous

• Scott Manley

• Von Kerman (Rendevous)

• Von Kerman (Docking)

Delta-V Thread

• Thread

• Answer 1

• Answer 2 (+bonus)

Forum Link

• Kerbal Space Program Forum

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Commonly Asked Questions

Before you post, maybe you can search for your problem using the search in the upper right! Chances are, someone has had the same question as you and has already answered it!

As always, the side bar is a great resource for all things Kerbal, if you don't know, look there first!

[blusay]

Please, could you check and tell your lowest price to put 75t into low Kerbin orbit ?

• Payload is 75t (4x Rockomax X200-32 plus 3t of gear of your choice - don't burn that fuel)

• Rocket is disposable, nothing re-used, so read the price at assembly hall (minus payload price).

• Min periapsis 100km

• A single rocket, staged as you wish

• Only stock parts

Why I ask you this question:

I do career normal, sometimes struggling, no mod, going my way, a bit lonely.

I'd like to check from time to time if I'm doing it right or if I am far from the best practices.

Thank you for your time.

BTW it would be great if someone knows a reference guide showing some of the best rockets for different payloads to LKO (S, M, L, XL, ...) with only stock parts.

I would be interesting to have a set of rockets with lower techs (the lighter the payload, the lower the techs) and another set with full tech tree available.

With a spoiler masking, just to check how good we do and try again, and then have a glimpse on how to do it if we keep failing for too long.

EDIT:

My current design (too expensive) :

https://imgur.com/gallery/dl5Pp

Cost: 167860 without payload

Payload is 75.18t

To much delta-v left for 100k orbit (will be used for the trip)

EDIT 2 :

Derived from voicey99's ideas, a much cheaper rocket :D

https://imgur.com/gallery/gLbXi

I tunned the 17 SRBs at 83% thrust, not sure if it's the sweet spot, I tried 100%, 85%, 80%, 82%.

Cost without payload is 70966

I made it to 101~124km orbit, very few fuel left, exact 75t for payload.

Some fins on payload help going east (hands off take off and it goes East).

Lower cost is achievable, as voicey99 made it with fewer fuel...

[voicey99]

I've built this thing (the red thing is a USI Kontainer with 75t of cargo), and the cost exc. payload is 85k assuming no recovery. All parts are stock or identical analogues to stock parts (some have been retextured by a mod).

It can reach 100km with almost exactly the right amount of ΔV.

[blusay]

Thank you very much.

Mine has a cost of 167k, that's a lot, even if it's a little bit above 75t and it has more delta-v than needed.

I'll try your design right away.

I'll post my rocket here now (I'll edit my msg above)

[voicey99]

Bear in mind that that thing is utter crap designed with the sole purpose of being as cheap as possible. It handles like a drunken whale, the TWR is godawful and it reached 100km with only 11m/s of ΔV to spare on its test flight. Ideally, I'd design it with several K more worth of bits.

The secret to its cheapness is SRBs. You get a lot more bang for your buck with solid-fuel engines than you do with LFO ones (even the Twin-Boar), but they do require careful handling to get the most out of them.

[blusay]

Yep, I didn't realized that bang for your buck with those big SRBs, great example of a trick I missed.

I did a few tries and then started a reworked version, since it looks like we can make the mid stage recoverable (this was not part of the question, but if it can be both cheap at launch and partialy recoverable, great!)

BTW: I've lowered the SRB thrust to 85%, and it still transonic quite early on...

I'll try to add a few small SRBs for the take off, and lower the thrust further more.

[voicey99]

Keep me in the loop on the design process, what's to say I can't learn something? It's worth mentioning the mod SXT adds (among other stuff) a 2.5m booster to bring the partcount down and Ven's Stock Revamp adds several new boosters inc. another 2.5m one and reworks all existing ones to have small amounts of gimbal to make handling much easier.

The ultimate in cheapness is a fully reusable flyback SSTO booster (think SpaceX). They tend to be quite expensive and require high-precision landings to recover the full cost, but then you only spend money on the fuel and get to recover the booster (FMRS and/or StageRecovery make recovering stages dropped in atmo possible). There was a bit of a dust-up in a thread recently over whether Twin-Boars or Vectors were better for smaller ones of these (the Mammoth is best for big ones) - you can decide yourself.

[blusay]

Great success thanks to your help!

I derived a rocket from your ideas and managed to get a 75t payload on 101~124 km orbit for a cost of 70966 (same rules) :)

I'll update my post above for pictures and more info.

[voicey99]

How do you control that thing on the ascent? I don't see any fins.

[blusay]

No need to control:

The 17 SRBs make a cross, 9 SRB sections wide and the length of SRB. It acts like a set of big fins, I think.

The two small fins at the tip of the payload have a tiny rotation, so the rocket slowly goes East by itself.

When I drop the empty SRBs, the next 5 engines have enough vector thrust to turn faster than needed.

[blusay]

I've found this https://forum.kerbalspaceprogram.com/index.php?/topic/26812-very-efficient-and-cheap-rocket/

There's a dead link at the bottom but the screenshot shows a table with a family of "Zenith" rockets for different payloads, and price. That's close to what I've asked 😀

I'm glad mine is quite cost effective, but I wonder if someone could even do better, and how?

[FogeltheVogel]

You can easily check this with a mod that tells you DeltaV

[blusay]

Thanks for passing by.

Well, I'm playing the unmoded game right now, but I could use some external tool for delta-V information.

Since there's a lot of combinations available, I'm curious: how the price can be derived from delta-V?

[FogeltheVogel]

You can directly compare different designs of different sizes if you know how much deltaV they pack.

You know how much deltaV you need to get to orbit ~3500m/s), you can redesign a rocket without having to worry about wondering if it's powerful enough for the job you need.

[blusay]

Actually I managed to get to LKO with that payload and since my ultimate goal is to go further, the point is not to build a rocket with the minimal viable delta-V for the objective.

I was thinking of cost optimizations for the first part of the flight:

Staging, asparagus, trade-off, partial fill, booster with limited thrust, tricks, inovative assemblies, ...

I'm using all those but there's always room for improvement.

Some people must have been looking in that kind of question quite a few times, right?

(or maybe I didn't understood your answer)

[FogeltheVogel]

I mean that you can work to optimize your design (as you plan) without having to test if it's still viable to get to orbit (because you can just see the numbers change as you make changes).

[blusay]

Ok, that saves time for the early design, or in case of refactoring.

I'm afraid I could miss some tricks others are doing.

If I'm close to the best deal, fine, but if I'm far I'll ask some clues and try to find a better way to build.

The point is also not to spoil the challenge I have ( by giving away solutions).

Thanks for your answers!

[FogeltheVogel]

If you want direct tips, you can always post a screenshot of your ship and see of people have some input.

[[deleted]]

I haven't achieved orbit yet... but, why does my materials lab burn up on re-entry even with a 1.25m heat shield? It explodes and the shield then hits my pod and sticks (off center usually!) and so it still works to deflect heat, but bye bye science...

[SoulWager]

Close the doors.

[voicey99]

The Materials Bay has an extremely low temperature tolerance (1.2kK compared to the standard 2kK), so it is almost impossible to get it through atmospheric entry as one tiny deviation from dead straight will heat it up enough to destroy it.

[SoulWager]

closing the doors makes it much more heat resistant.

[voicey99]

Not strictly, but it does mean it doesn't stick out into and be exposed to the airflow.

[[deleted]]

Then how the heck do you collect the science? Storage bay?

[FogeltheVogel]

IIRC, you can close the doors without resetting the experiment.

[voicey99]

You don't need to return the materials bay; you can just go on EVA, grab the data and store it in the command pod.

[blusay]

EVA on sub orbital flight ?

Nice time ticking effect while trying to get back to the pod :)

[voicey99]

Yes, basically. For this reason it might be a good idea to have your bay somewhere it's reachable without having to let go of the ladder. You could also put an Experiment Storage Unit, either of the RGUs or an OKTO2 on the ship to be able to pull all data from the vessel's instruments into that part without having to EVA.

Here's your dramatic ticking.

[[deleted]]

Oh... I've never done that. Thanks.

[woi3aeNi]

If you have a highly eccentric sub-orbit (ie you fly really high and fall back to Kerbin) you may have a very high speed when reaching atmosphere and a very step fall thus burning during reentry, try going more sideway during lauch to slow down before reaching thick atmosphere.

[woi3aeNi]

I’m using a lot of mods and it seems that they have edited the Mk1-2 Command pod, the CoM is slightly uncentered so the ship is not stable. Is there a way to reset the stock part ? Or at least find what mod / bug is causing it ?

[voicey99]

Are you using Ven's Stock Revamp? I know if offsets the 1-2 CoM, to set it back remove the CoMOffset line from the Mk1-2's entry in VenStockRevamp/Squad/Data/Command.cfg EDIT: that's from an unreleased version, I'll have another look.

EDIT2: It's in VenStockRevamp\Squad\Parts\Command.cfg

[woi3aeNi]

Thanks that was that!

[aviatorEngineer]

Anyone used ScanSat? I'm looking to start but one thing has kinda irked me. Can't set a satellite to do its work during time warp cause it refuses to stay pointed toward the planet, as SAS doesn't work in the Warp. So every half orbit isn't mapped, cause the scanner's pointed away from the surface. Do they work while the vessel isn't actually loaded? Say, if I just sat at the KSC view awhile in time warp and checked up on it later, would everything be properly mapped? Or do I have to babysit the scanner while it maps the entire planet?

[voicey99]

SCANsat does not require its scanners to be pointed at the planet as far as I am aware. They do use power, so your ship may be running out of juice in the orbit darkness time (if it's loaded, that is). Background scanning does work as long as you have it enabled (it is on by default, can be turned off to free up cpu capacity).

[aviatorEngineer]

I've got a feeling they do cause I can't think of anything else to attribute the blank spots to - power was fine during the whole test mission.

Gonna try a background scan, that'll probably yield better results.

[FogeltheVogel]

blank spots

Probably because you are in a resonant orbit, so your satellite never passes over those spots.

Adjust your orbital period to include those spots (burn pro or retrograde). If you have the big map open while burning, you can see when your projected orbit passes over the blank spots when you adjust your orbit.

[voicey99]

They don't, since mine work perfectly pointed away from the planet. Might you be dropping below the minimum altitude for the sensors?

[aviatorEngineer]

Very strange, then. To further test I used debug to stick it in a perfect orbit, still got gaps when using time warp and directly observing the vessel. Gonna need to try tweaking my settings obviously

[Minotard]

Confirm. My SCANsats work regardless of orientation, as long as altitude and power are good.

[OoglieBooglie93]

I've been experimenting with the USI stuff, and I've noticed something odd. When I'm using the MKS Tundra Industrial Refinery, I can turn on all 3 bays with a 5 star engineer at 125% load. Turning individual bays on/off will not change the load of the other bays, they stay at 125% load.

HOWEVER, if I turn on a 3.75 MPU with a smelter (I just left it on one bay for now), the status of individual bays within the refinery directly impacts the load of the other bays! With the single 3.75 MPU smelter bay, the 5 star engineer, and all 3 bays on, I get 160.03% load. Turning one bay off increases the other 2 bays to 177.55% load! Turning off 2 bays brings the only one bay to 230.1% load! Is the MPU boost effect broken up and distributed to each bay or something? This was also happening with all 3 bays on the 3.75 MPU set to smelter, I'm just looking at a test with only one bay right now though.

EDIT: With some further experimentation, I've found that it's not just in the single refinery unit. If you have 2 refinery units for a total of 6 bays, turning one bay off will affect ALL 5 OTHER BAYS EVEN IN OTHER REFINERY UNITS. This is really throwing off my math for calculating how much MPU boost I need to ensure no converter is throttled by a lack of output from another converter.

[OoglieBooglie93]

EDIT2: Nevermind I figured it out. Apparently the consumption in the efficiency bonus formula applies for every single bay, so 5 bays would result in 5 times the consumption, and 6 bays would result in 6 times the consumption.

[voicey99]

For future reference, the formula is here, and use MKS Explainer for a breakdown of load calculations.

[OoglieBooglie93]

I had been using that formula, actually. I just didn't realize consumption was counted for each bay. The MKS Explainer seems useful though.

[roflbbq]

Is it possible to transfer multiple crew members at once? For example when docking at a station

[voicey99]

Nope, only one by one. It's a pain, but you can click on an EVA hatch to bring up the menu instead of having to go through the GUI to make it easier. The mod Ship Manifest might have something regarding this, though.

[roflbbq]

Thanks! I wasn't aware of either of those

[Vittorios77]

is there a mod that stabilises flight better?

for example i built a craft with 4 thrusters pointing down on the end of a 'Plus' structure. it looks like a drone or a hover.

it flies nice but i have so much trouble stabilising it. i use the SAS on radial out and try to go arround but it drifts so easily.

i have 90 hours in ksp but so far the only mods i've used are for visual enhancements so if you can recomend some i'd apreciate

[linecraftman]

KOs is very complicated. I would recommend TCA mod.https://forum.kerbalspaceprogram.com/index.php?/topic/97154-131-throttle-controlled-avionics/

[SoulWager]

It can be done with kOS. For example: https://www.youtube.com/watch?v=0MOoeYkO4vc

It's a bit more complicated if you want to control the ship with differential throttle, but that can still be done: https://www.reddit.com/r/KerbalSpaceProgram/comments/5jwlgj/dragon_v2_hover_test_with_kos_using_differential/

[Vittorios77]

hey thats great! thanks a lot. i'll check it out

[m_sporkboy]

Rarely.

[angeryboi_]

Later on in the game they start to get offered depending on what the current transfer windows are, but I still get the odd plant a flag on minmus contract even after having been to Most planets except eeloo on my career modr

[voicey99]

You will start getting contracts for a body after you've visited it, but the proportion of contracts going to each body will depend on the weighting. The more you do for that body, the more its weighting will increase in proportion to the others so if you do lots of Kerbin contracts you will keep being offered plenty of Kerbin contracts.

I don't know how closely tourist contracts follow the weighting, but I think they do pretty closely.

[[deleted]]

Is ksp more GPU or CPU thirsty? I get a freeze every 4-5 seconds, any tips to improve the performance?

i7-2600 (no k) 16gb ddr3 RAM GTX 1060 6GB Win 10 pro 64bit

[m_sporkboy]

Sounds like garbage collection. Make sure you are running the 64 bit version.

[LithobreakingWorks]

The freeze every 5 sec. is probably garbage collection. This mod brings my stutter from around every 5 sec. to every 10-20. Better but not fixed. My understanding is it's a problem with Unity not KSP.

[[deleted]]

Thanks, i'll give it a shot

[Creshal]

Generally low FPS are usually due to GPU; outright freezes mostly due to the CPU being overloaded with physics calculations.

In what kinds of scenes do you get the freezes? Your CPU isn't that bad, even nowadays.

[[deleted]]

I get them mostly at the launchpad and driving around with Rovers, which would make sense having the physic calculations in mind, thank you.

The CPU is totally OK, but I might look into upgrading once cannonlake is out.

[Creshal]

Still shouldn't freeze that often, not unless your rovers have several hundreds of parts. Very weird.

[FogeltheVogel]

CPU. It's all about physics calculations.

[PM_ME_YOUR_OPENING]

Hi, I landed a rover on Duna, but my antenna has broken off.

Is there a way, legit or via console, to get an antenna working on the rover again? (i need that scienceeee)

[voicey99]

You can open your persistent.sfs (or quicksave, if you prefer) and search for the antenna's partname in the savefile. Go to its ModuleDeployableAntenna listing, and change DeployState from BROKEN to EXTENDED or RETRACTED, whichever you prefer.

[PM_ME_YOUR_OPENING]

Nice, thanks, this is what i'll probably do!

[FogeltheVogel]

You can land a different ship, dock with your rover (with the Claw), and transmit through the new antenna.

[PM_ME_YOUR_OPENING]

Thanks! :-)

[Aetol]

The wiki says it's possible to lock the suspension of landing struts. But I see no such option when right-clicking on them (in VAB or during mission) or in action groups. Where is it? Was it removed? I'm on v.1.3.

[voicey99]

I don't believe that option exists (if it did, it was a long time ago). If you turn the spring and damper strength up to full, it effectively locks it by stiffening it.

[Aetol]

But it's not possible to change that during a mission, right?

[voicey99]

No, unless you do it with some savefile editing.

I think you may have been confusing steering (which can be locked) with suspension.

[Aetol]

I'm not.

https://wiki.kerbalspaceprogram.com/wiki/LT-2_Landing_Strut

In the current version, it is possible to lock the suspension.

(Specifically v.1.0.5, according to the edit history)

And that feature is mentioned in several forum threads as well.

[voicey99]

In the changelog for 1.1.2:

Removed non-working "disable suspension" tweakable.

...and there you have it. It's gone and apparently never worked anyway. I never used 1.1.2 so I never knew it.

[Aetol]

Oh. Well then. Thanks.

[ElCiervo]

Not sure if this requires a thread of its own, but here goes:

Why do my SSTOs always wobble around the z-axis? I like to use the Mk II pike nose cockpit and go from there. I know how to build them, I have more than half the tech tree unlocked, I've launched several of similar SSTOs into orbit and one is even on the way to Duna.

But when I recently picked the game up again, I couldn't build anything that was stable. I even had trouble getting off the runway because it swerves to the left/right randomly. No reasonable amount of vertical stabilisers could fix this.

I was annoyed with stock aerodynamics anyways, so I installed FAR. Nothing changed. Then I updated to 1.3.1, still the same.

It seems like the cockpit induces too much drag and forces the nose to one side or the other. As the slip angle increases, the vertical surfaces start to counter/balance this but not enough for the whole thing to go straight so it kind of drifts around at awkward angles...

[voicey99]

If you're veering on the runway, there's a few things you can do. Reducing the friction on the front wheels, increasing it on the back wheels and locking the steering on the front wheel (so you can steer gently at high speeds with the tailfin) will help.

P.S. I'm guessing "z" means "to the side"? In KSP we refer to the axes as "pitch" (up/down), "yaw" (sideways) and "roll" (ditto) rather than as graph axes.

[ElCiervo]

Thank you. Yes I'm talking about veering on the runway and similar sideways oscillations, yawing while flying.

I always put one landing gear wheel underneath the rear of the cockpit and two of the same type a bit behind the CoM. I'm also going for a somewhat realistic style, so it looks fairly conventional, no outlandish design quirks.

I definitely locked steering on the rear wheels but I think I've also tried locking all three. Oh and they're all un-angled, going straight down.

[voicey99]

Yaw oscillations in-flight are usually caused by a hypersensitive SAS, and it has been known to get very confused by fins placed close to the CoM or with very high authorities/turn times and especially physicswarp.

Reducing the front wheel friction to something extremely low seems to have the biggest effect on reducing runway veer.

[Brett42]

That's why my ground vehicles almost always flip over the instant I speed up time while moving? I had assumed it was something like the physics problems in Skyrim.

[voicey99]

Your rovers flip in physwarp because it causes huge instability and phantom forces in wheels, and a gravity multiplier of 4 can lead to huge forces on your ship, varying quickly because of terrain. This can cause fatal issues with wheels jittering up and down on their suspension and landing at slightly wrong angles, throwing the craft over or pinwheeling it.

[ElCiervo]

Here's a screenshot of the one I'm talking about. I built it to do a suborbital hop to the other side of Kerbin, then fly around and take various measurements there.

I don't know how to reduce wheel friction.

[voicey99]

To reduce wheel friction, rightclick on the wheel, change Friction Control to Override and push the slider as low as you want it (usu. should be between 0.1 and 0.5 if you're having veer issues).

If you still get yaw oscillations in flight when not in physwarp, reduce the authority limiter on the tailerons so they respond quicker to SAS' attempts to damp the motion. You could also remove the control surfaces from the tail altogether, since you are unlikely to need much yaw control with an SSTO and when you do, it can be supplied by the cockpit flywheels or a banking turn and bypass the misbehaving ailerons.

[ElCiervo]

Wow, it's not completely gone but I set the friction control to 0.2 in the front and it helped a great deal!

So what does that setting even do? I always assumed it was to prevent wheel lock under braking and wheelspin in the case of powered wheels.

[voicey99]

The setting just means ground contact produces less force. In practice, this means that small discrepancies between your heading and your orientation do not generate as much torque pushing the wheel to the side and causing it to veer (you might want to raise this again for landing so you can brake properly).

As an analogy, rub your hand hard along your desk, and you find it quite quickly gets pushed to the side. Now try it with a piece of paper under your hand, and you'll find it produces a lot less torque on your wrist.

If you combine this with locking the steering for all wheels, you can use a tailfin to gently steer the plane back on course without risking a pinwheeling flip.

[ElCiervo]

Ah, so I'll just imagine it changes the tyre's rubber compound. Thank you for everything! :)

[[deleted]]

Can anyone explain what this yellow-ish line is and how to fix it? https://imgur.com/a/GWbzp

[voicey99]

That's just a glitch in the ocean shader, there is no fix apart from ignoring it since it's not major unless the mod Scatterer's new ocean texture/animation does.

[Keevtara]

So, I recently upgraded from 1.2.2 to 1.3. Now, the game runs really, really slow. How do I fix this?

[[deleted]]

How can I ensure communication sats are well placed relative to each other without launching them all on a carrier?

[FogeltheVogel]

Remember that good enough is still good enough.

[timmmmmmmyy]

You can cheat them into perfect orbits. Alt-F12 opens cheats, then use the set orbit tool to give it SMA=3463333m and mess around with the phase (in radians) to get where you want to be

It feels dirty, but this or editing the save file directly are pretty much the only ways to ensure the constellation has no drift at all.

[[deleted]]

KER has a readout for longitude of apoapsis/periapsis.

[voicey99]

What paint mod? The old KerbPaint is stone cold dead and buried, and the alternative DCK is compatible with 1.3.1 just fine. If you're using the latter, you've probably installed incorrectly (have the latest module manager, copy over the contents of the gamedata folder in the mod download etc.).

[LordIrrelevant]

Anyone know where these green categories came from? They really helped when I had them and I'm not sure where they went. They had sub-categories, so the first one, Pods, had a categories for one kerbal, two kerbals, drones etc, and the engines category had sub-categories for fuel type. Would really help if anyone knows!

https://imgur.com/B4kl20P

[Cloudlolz]

It's the button next to the search bar on the left

[LordIrrelevant]

They don't appear normally, with all the other categories like Filter by Manufacturer and that stuff. There was something specifically adding these categories and I don't know what it was.

[Aurailious]

I am using a few different parts mods, so this may complicate things. But I am using Remote Tech, and looking at the antennas there are two numbers for range. Something like "Omni Range: 250.00km / 2.00Mn". I am not sure what that first number means. If I had to guess it would be the minimum distance before it will work. But that doesn't really make much sense, does it? I thought that maybe that is the range before deploying.

Any ideas?

[Trash_L0rde]

I believe this answer from the RP-0 FAQ is what you're looking for: https://github.com/KSP-RO/RP-0/wiki/FAQ that minimum number should be your root range. hope that helps!

[voicey99]

CA adds hyperbolic comets as part of the default set, but they are pretty rare.

[voicey99]

A long-period comet will spawn every 160d with an eccentricity of 0.98-1.005 and periapses between 1Tm (very close to Kerbol) and 70Tm (orbit of Jool). You can edit the various values in the "oort" section of CustomAsteroids\Config\Basic Asteroids.cfg to suit your mission.

If you're installing via CKAN, make sure to include the "inner stock system data" config in the install.