jimmymcgoochie

That sounds more like a phantom force than a problem with Principia. If you use the 'set orbit' cheat and position an identical probe in a similar orbit, does its orbit also change? If you save and reload, does the orbit keep changing? I'm not sure how much visibility this post will get here, but if you go to the RO/RP-1 discord server there's a dedicated channel for Principia-related problems and you're much more likely to get help there. https://discord.gg/6EFMFsnT

Which service bays are you referring to, the stock ones? There’s a big difference between a service bay and a service module, the latter of which will hold supplies etc. The Kerbalism config engine is only meant to be used in the VAB or SPH to get the right ratios of food/water/oxygen or liquid hydrogen/liquid oxygen for crew and fuel cells respectively. If you’re using fuel cells, though, you’ll have a nearly-continuous supply of water and if you have a lox-to-gox converter then you’ll have a supply of oxygen too, so use the config engine as a guide but pack loess water and oxygen than it gives you. The Kerbalism window should be on the (stock) toolbar on the bottom right of the screen in the VAB/SPH. There are two Kerbalism buttons- one opens the vessel information which gives you the estimated time your power and supplies will last in the VAB and gives you control over science experiments and processes in flight, while the other shows all science experiments and which ones you’ve completed where, which can be filtered to only include the experiments on the current vessel to show if you’ve already completed them or where there’s some science left to be gained. They should be right beside the stock message button, both have an ECG (wiggly line) and either a transmitter dish or (I think) a science symbol . Screenshots would help.

I forgot one of the golden rules of KSP, with predictable results: Always- ALWAYS!- check your staging. Stupid launch clamp was one stage up from where it should have been, so the rocket was stuck on the ground until the next stage fired and detached the boosters at the same time. Whoops.

Making a geostationary contract satellite wasn't as difficult as I thought it would be- a three-stage 350 ton rocket is enough to put 2000 units of payload into GEO orbit with plenty of fuel left to get to a specific longitude. With that design completed, it's time for some real missions as 1967 begins with a Mars transfer window. Montage! Green Kiwi 1: The second stage engine was swapped from an RD-0110 to an RD-0213 which provides a lot more thrust, something that future missions using the three-stage setup will copy. I had to angle the rover so that the skycrane wouldn't block the solar panel, but it seems to be working well enough. Blue Guitar 1: Staggered staging on the solid boosters didn't work, the second trio were still burning when the first stage ran out of fuel and had to be dumped. The transfer burn took about ten minutes in total and required a significant amount of off-plane burning, which required a significant course correction burn to get on course for Mars. I may have to drop the landers early and hope they can survive a direct descent. Green Kiwi 2: Launching later in the transfer window than its sibling, this mission will take a slower but lower-energy route that should leave it more fuel to slow down before hitting the atmosphere. Only requires a small course correction, unlike the other Mars-bound missions today. Blue Guitar 2: The transfer window was more favourable for this Blue Guitar, resulting in more fuel remaining and a smaller course correction to compensate for the looong transfer burn. And following close behind all those was Blue Mandolin Vesta. No fancy multiple probes on this one, just a single orbiter that should make it to low Vesta orbit and transmit a whole heap of science. In between all the launches, Green Bananas 2 and 3 had their own course correction burns to get on course for low flybys of Mercury. Both probes will arrive within a few days of each other and scrape up a lot of science. I think I might try to get a second flyby with one of them to increase the science gains, though it might be difficult to do so. Coming soon: With the interplanetary stuff out of the way for a little while, it's time to focus on crewed missions again: an Earth orbit space station and a second crewed Moon landing. Better get those astronauts trained up again...

You’ve fallen for the trap of the stock resource display- just because it seems to suggest there’s ore there, doesn’t mean there actually is. You need to increase the cutoff to at least 50% to filter out the dross and be left with the real hotspots. Ore is biome dependent, so find a biome with good concentrations and all the locations of that biome will have similar levels.

If you have RCS on the shuttle, use that to move the shuttle away from the satellite; alternatively use the satellite’s propulsion system (you do have one, right?) to give a brief impulse away from the shuttle. Alternatively, mount the satellite on a decoupler that’s angled so that when it decouples the satellite gets thrown out of the shuttle payload bay with the decoupling force.

The Kerbol system is too similar to Sol system, as are a significant number of planet pack mods. Most exoplanetary systems found so far look nothing like our solar system, yet the pattern of small to medium rocky planets near the star, gas giants further out and some random icy lumps at the outer edge is almost ubiquitous in KSP. In trying to make the Kerbol system more like Sol system for familiarity’s sake, I think a great opportunity was lost to make it something more unique and interesting.

Use the non-retractable solar panels, they’re cheaper and lighter. You should also look at KerbNet when in a polar orbit for resource scanning and use it to mark locations which have a lot of ore and relatively flat terrain, then use those navigation markers to aim at when landing a mining vessel later. Not all probe cores are equal though, so add a RoveMate on top of the scanner as it has the widest field of view and can cover the biggest swathe of the surface in one go. At this point I’d usually suggest using SCANsat for its advanced mapping systems and BonVoyage to drive rovers on the surface and scout out promising locations, but since you’re not using mods…

Every time you start timewarp the physics system has to switch to “on rails” and this can introduce small imprecisions; the greater the jump in speed, the greater the imprecision will be and the more your orbit can change. Always start timewarp yourself by bumping it to the first speed, then click the “warp to node” button or speed it up yourself. It’s also a good idea to slow down timewarp before SOI changes or your trajectory can shift too- KSP does this automatically, but at high timewarp speeds it might not slow down fast enough.

The idea of “real-scale” planets is the Japanese knotweed of KSP2, no matter how many times you try to burn it down it just. keeps. coming. back… Kerbin orbit velocity just above the atmosphere is about 2200m/s; just above Earth’s atmosphere it’s over 7800m/s. A rocket that can just get to low Earth orbit has the delta-V to fly to the Mun, land and then come back to Kerbin orbit again without aerobraking. KSP parts are woefully underpowered for a 10x upscale, but rebalancing them to work at that scale makes them stupidly overpowered for stock scale. There’s also the not-insignificant issue of how few KSP players can actually fly into orbit, let alone go somewhere else after that; making bigger planets would only make that worse.

Yeah, ore drills only work if there’s actually ore in the ground to drill…

I think this is the launch of Blue Violin 4 to the Moon, but honestly I can't be sure. It might be some super-secret prototype that I was testing and just forgot about between then and now. Given that the next screenshots after this are of Blue Violin 4 going to the Moon, I'm going to assume that this is it launching. The upper stage had to be discarded with a significant amount of fuel remaining because the lander's TWR is so low when fully fuelled that it can't actually land safely without burning off a lot of fuel first. A flaw that I may correct in future, if I decide to launch any more of these missions. With that lander on the surface I took some time to cull the craft list, discarding debris, dead probes and missions that just didn't work any more. One that survived the cull is Blue Violin 2's lander, now in orbit of the Moon, which got its orbit adjusted to get even more science. With transfer windows approaching and contracts available, I did a burst of mission designing: a Venus mission adapted from the Blue Guitar multi-probe missions and fitted with four Venus-spec landers; a Mars rover based on the Green Huckleberry Moon rovers but with a skycrane above the rover instead of a landing stage under it; and an upgraded Green Cucumber contract sat launcher that can carry 2000 units of payload and is only marginally more expensive than the existing 1500-unit design. I've also had a rummage through the newly unlocked parts and configs to see if there are any upgrades I can make to existing designs. A few show promise, but aren't yet finalised so aren't ready to be shown off yet. Following a month-long stay on the surface, Blue Violin 4's lander returned to orbit and docked with the return probe within twenty minutes of lifting off. With the return probe's tanks topped up and batteries recharged, the lander undocked and remained in lunar orbit while the return probe set a course for home with the precious sample on board. Interrupting Blue Violin 4's return was Green Banana Mercury 3, launching into the optimal Mercury transfer window. Yet another engine has mysteriously lost data units- the RD-0110 in the second stage has dropped to a little over 2000du when it used to have the full 10k, though reliability is still very good and no problems occurred on this launch. And a few days later Blue Violin 4's return capsule blazed a trail across the mid-Atlantic sky as it re-entered, enduring some pretty brutal deceleration of up to 15g as it did so. A successful mission, and a vital injection of much-needed funds which were getting critically low: Three missions are currently under construction for the upcoming Mars transfer window, a fourth for Vesta and another for Venus; there's also a space station partially built and awaiting its turn in the VAB again and a Ceres mission at the back of the queue. A second lunar landing is also on the cards at some point with both parts also on the queue, while a crewed LEO Gemini will be needed to visit the station and complete that valuable contract. That should keep the VAB crews busy for a while. Coming soon: A bit more design work, possibly a geostationary contract sat and the first launches to Mars.

@seyMonsters what you’re getting with the stage that won’t stage is easily resolved- put a blank stage 1 below the stage with the RCS etc. in it and stage them both, the staging system gets confused sometimes when you separate vessels like that but adding an extra empty stage usually solves it. To my knowledge, RealAntennas and Kerbalism together seem to consider the signal bandwidth per vessel, so in theory multiple probes can use one relay and all will get the full data transfer speed rather than it being divided between them; or at least that’s what I’ve seen. And as for the upper stage, it’s probably acting oddly because the avionics were set to debris on staging and debris can’t be controlled. Hire Earl Jones and nickname him “James”

Sounds like a centre of mass/lift imbalance, those rocket engines right at the back will make it tail-heavy and with the tanks empty it would be prone to flipping tail-first, not helped by the tailless design. Move the main wings back and give them a slight upwards incidence (tilt a few degrees up so the leading edge is above the trailing edge) and add some sort of tail fin and you might find it a lot more flyable, or add some ballast in the nose to prevent the CoM shifting too far back.

I don’t see the need to add fancy ores, just put the resources themselves in the ground and have drills to dig them up as for ore in KSP now. This area/biome has lots of water in its surface, be that liquid water, ice, hydrate minerals etc., that’s all you need to know. Having complicated production chains would detract from the “building and flying spaceships” thing that has repeatedly been stated to be the core of KSP2. Might as well throw in my own two cents/pennies/whatever’s worth: Liquid fuel (kerosene fits best, but it could be liquid methane); Oxidiser (liquid oxygen, or hydrogen peroxide if LF is methane- Kerbalism certainly thinks so); Monopropellant (hydrazine); Xenon; Solid fuel (probably metal-based); Metallic hydrogen; Fusion fuel (for fusion rockets- helium-3, deuterium, tritium, some combination thereof); Fission fuel (mostly for reactors- uranium, plutonium, thorium…); Fission pellets (for pulsed fission drives such as Orion) Fusion pellets (for reactors and pulsed fusion propulsion such as Daedalus); Antimatter? Colony supplies (some combination of food, water and oxygen to keep colonists happy and working hard); Waste products (from Kerbals…); Metal (very generic, used to make both ships and base/colony structures). Even that list seems like a lot considering stock KSP only has the first five. Adding in different ores that have to be mined and processed to then begin producing even more materials would become a logistical nightmare; I thoroughly enjoy games like Dyson Sphere Program which feature that sort of production chain system, but it wouldn’t fit nearly so well in KSP2. Keeping resources simple also means that ISRU and production chains can be simple too- ore can be turned into liquid fuel, oxidiser, monopropellant and ore plus metal makes solid fuel; metal plus fission fuel makes fission pellets; fission pellets plus fusion fuel makes fusion pellets. Xenon can be found in some atmospheres, antimatter could be found in low orbit above certain planets e.g. Jool or generated using a dedicated colony reactor that eats a ton of power to do so, while colony supplies could be generated from a combination of ore, waste and power to eventually create a closed-loop system instead of sending them from Kerbin.

‘Like’ isn’t exactly the best reaction… Get well soon

How to make a Mars rover in three easy steps: Take an existing design for a Moon rover; Add a parachute; Uh… moar solar panels I guess? Getting to Mars isn’t that much more difficult than getting to the Moon, with the added bonus of having an atmosphere to aerobrake in once you get there (even if it’s a really puny one) and a parachute-assisted powered landing is easier than a purely propulsive one.

Every body in the Kerbol system has something to dislike about it, if you try hard enough: Moho takes a lot of delta-V to get to and from, with a relatively small SOI making orbital capture more difficult with the long burns you need to get that delta-V. Eve is evil, high gravity plus thick atmosphere makes it incredibly difficult to get off of Eve, while the high orbital velocity makes it hard to get down without getting cooked and getting into and out of low orbit requires a lot of delta-V. Gilly's gravity is so low that it's very difficult to land, and stay landed, plus its SOI is very small compared to Eve's and so it's quite hard to get to as well. The Mun has so many biomes that it's all too easy to clean up the entire tech tree without going anywhere else, plus the day/night cycle is long so solar-powered vessels are likely to run out of power during the night. Minmus is an oddball that's harder to get to than the Mun, with far fewer biomes and terrain that's either perfectly flat or very steep, plus it isn't nearly as deliciously minty as everyone seems to think. Duna has just enough of an atmosphere to be annoying (breaking solar panels etc.), but not enough to be particularly useful (good luck getting parachutes to work) and the terrain is pretty forgettable. Ike is like the Mun, only smaller and more boring, plus the mutual tidal locking with Duna means it gets in the way of a lot of Duna-bound missions. Dres is... well, Dres. 'Nuff said. Jool looks nice, but you can't land on it and orbital velocity is immense; with very little solar power you'll probably need RTGs or fuel cells for power or a lot of batteries and slow science transmission. Laythe has almost no land to land on, a thinner atmosphere than Kerbin meaning wings generate less lift and jets generate less thrust, and did I mention the lack of land? Oh, and most of that land is very rugged with almost no flat areas so have fun landing your very expensive plane. Vall is a pretty missable little blue lump, the biomes are out of order and there's not really much to see. If you're using Kerbalism, Vall is the deadliest place to land in the entire Kerbol system because it's right in the middle of Jool's radiation belt and lacks the protection that Laythe's atmosphere offers on the surface there. Tylo is an absolute pain- equal in size to Kerbin with only slightly less gravity, it requires more delta-V to land on than anywhere else due to the lack of atmosphere to aerobrake in, needs just as much delta-V to return to orbit afterwards and there's not all that much to see down there; it also has a tendency to give you gravity assists that can throw you down into Jool's atmosphere or completely out of Jool's SOI, whether you want it to or not. Bop is a lumpy potato miles off Jool's orbital plane, hard to get to and not much to see there once you get there (with one notable exception...) Pol is also a strange little lump, even further from Jool than Bop and with some potentially nasty terrain. Eeloo is so far out that it's hard to get to, solar power is effectively zero and it's not all that interesting when you get there. Of course, they all have their good points too...

Screenshots alone aren’t enough to diagnose the problem, for that we’ll need logs and a full mod list. However, something you said gives me an idea: are you playing KSP with mods through Steam? This is A Bad Idea as Steam can cause corruption in modded KSP. The simplest solution is to make a copy of KSP (with no mods installed) and then install your mods into that copy, leaving the Steam one untouched so it doesn’t meddle with anything.

Lab modules are cheating- you can put every experiment in each lab module and it will produce all the science each time; put the same experiment data into a different lab, even on the same vessel, and it’ll process it again for double the rewards. By the time you get a functioning orbital lab running, odds are you’ll be doing a lot of timewarping for long-term missions so the wait times will be minimal and the science gains will be huge, though by that point you’ll probably have the entire (stock) tech tree completed. Labs have the added bonus of being able to restore experiments like materials bays that would otherwise need a Kerbal scientist to make them usable again. You can also store multiple copies of any science experiment on the same vessel either by having a Kerbal collect the data and store it in e.g. a crew pod, or by adding experiment storage boxes which can store the data even without crew. Take several copies of every experiment, put some in a lab (or labs) and return the rest to Kerbin to maximise the science points gained, since most experiments need several runs to get the full data and will only give partial rewards for transmitting the data (materials bays are a good example). Transmitting data means reduced science gains, but it’s a lot easier than doing a sample return mission.

Don't use the version on CKAN, go to the GitHub link listed on CKAN and download the master branch, then install manually following the instructions on the Readme. https://github.com/raveloda/Coatl-Aerospace If that still causes issues, delete any parts that are blocking the game from loading and retry. The mod works for me in KSP 1.12.3.

That’s the rocket equation for you: delta-V has hard limits based on your ISP and mass ratio. You can either try to increase your mass ratio by using lighter, more efficient tanks (e.g. using lightweight aluminium-alloy balloon tanks) or increase your ISP by using different propellants and/or engine types (e.g. switching to hydrolox or even nuclear thermal rockets), but there are problems with both- fancy tanks are expensive and difficult to make, hydrogen is very un-dense and needs larger tanks than other propellants and NTRs are heavy with a relatively low TWR. Ion thrusters using e.g. xenon provide vastly more delta-V due to their extremely high ISP, but their thrust is incredibly puny in comparison. The largest rocket I’ve ever launched in RO/RP-1 put 650t in low Earth orbit- I actually launched that thing six times carrying the propulsion modules for crewed Mars and Venus missions, plus a one-off mission that had well over 30km/s in total thanks to extremely efficient hydrolox rockets, just to put a one-ton lander on Mercury’s surface. Total launch mass was at least 12kt each time, limited mostly by the size of tooled tanks and how many boosters would fit around the core stage.

Autostrut all engines to the root part, it makes them much more stable and less prone to pushing themselves inside whatever they’re attached to when using physics warp; it also helps to autostrut some key components to the root part to maintain the rigidity of the craft along its length. Autostrut boosters to grandparent as it makes them far less wobbly, especially when you attach things to the boosters (e.g. nosecones or fuel tanks) as they autostrut each part to every booster. Autostrut heaviest is Kraken bait and should not be used, the heaviest part changes after staging and can really mess up your vessel. When docking stuff together, turn all autostruts OFF or they’ll recalculate when you load the vessel and lead to horribly warped vessels with parts bent in all directions.

After some experimenting, I've come up with a new plan for the big Mars mission: remove one of the moon probes and push right up to the 700 ton weight limit to maximise delta-V. One of these is already under construction, with a second added to the build queue when I checked and found out that the real Mars transfer window is actually a lot later than KAC said it would be. Another upgrade to the Blue String rocket, the Block 2B features uprated RD-253-Mk2 engines which provide noticeably more thrust. First to test this new config is Blue Violin 4 on its way to the Moon: The probe captured into a nice low orbit of the Moon, however the entire near side is in darkness right now so it'll have to wait for a while before landing. The return probe was detached and left in orbit while the lander waited for the right time to land, mopping up some low orbit lunar science in the process. While waiting for the Moon to spin around, Green Banana Ceres arrived at its destination. No flukey resonant orbits with this one, just a single flyby, so it used up most of its remaining fuel to slow down as much as possible to maximise the time spent gathering data. A Mercury transfer window is opening and two probes will be sent there- Green Banana Mercury 2 and 3, both flyby probes since capturing into Mercury orbit is ridiculously difficult. 2 will launch now, while 3 waits a little longer. Everything worked as planned thanks to the very high reliability on all the engines and the probe is on its way to Mercury now. Capturing would take another 8km/s, which this probe doesn't have. With all the science coming in and some big contract payouts and advances, the third VAB queue is now up to the same speed as the first two: Future KCT points will mostly go into R&D to unlock new technologies faster and try to keep those VAB queues busy. Coming soon: Mercury and Mars missions and possibly the launch of a space station.

Maintaining a full 1g isn't really necessary: Earth has the highest gravity of anything you could feasibly be landing on in our solar system and (after discounting Venus for obvious reasons) nothing else comes close to that; Mars and Mercury are both less than 0.4g, Ganymede and Luna (Earth's Moon) are less than 0.2g and it only goes down from there. Assuming that this hypothetical spaceship is going to Mars, why maintain a full 1g when reducing it to Mars gravity will help the crew adapt to the conditions they'll find on the surface, reduce the mechanical loads on the ship's structure and will also help to negate the disorientation that can arise when your senses disagree on whether you're standing still or moving. As for a T-shaped ship, it would be vulnerable to Dzhanibekov effects which would be very unpleasant for anyone on board. See the EVA experiments kit added in KSP 1.11 and at 22:20 in this video, for example: Not something you want to have to put up with for years in space.