Kerbal Space Program

I hit ~1200m/s and it slingshots me high enough to circularize my payload.

Making a plane spaceplane capable is just too complicated. Much easier to design a payload that can finish the job by itself than to massively complexify your ramjet sled.
 
Is that a pair of the JX4 Whiplash engines on that space plane? I briefly tried building a space plane that can get into orbit on its own, but I used those RAPIER engines. I read up some tutorial and that's what it said to use.. but my problem was that I could only get up to 1,000m/s and about 15km before starting to lose engine power. In one of my designs I have 1 NERV engine too, so I can try to circularize once I get as high as I can get, but that got me nowhere. I only tried for a couple hours though, then gave up and moved on to something else.

I also now have a huge problem. I can't undock two ships I have that I have been docking and undocking all the time. One is a lander and the other is a tug. I am trying to land on Bop and am in orbit, but when I right-click on the only docking port (out of the 2 that are docked together) that gives me an "undock" option, and click on that, nothing happens. I stay docked and the option to undock disappears. I know that I am still docked, because when I fire up the RCS thrusters, they fire up on both ships. I tried... rebooting. Not sure what else to try, but online it seems to say that it's a bug and that you have to edit your savefile manually and hope for the best. But the last post about this I could find was from 2 years ago, so I was hoping for a better fix.

It's preventing me from continuing project ZEUS. I can now land on the 4th moon of Jool and might have enough fuel to land on the 5th without having to replace my 2nd asteroid. So I can maybe almost finish my mission, but then... this
Dude that docking bug sounds like a real pain in the butt. Are you going to go through the trouble of editing your way out of it?

I just ran into an equally stupid situation involving docking. I took two contracts - the first was to dock two vessels at the Mun and the second was to plant the flag on the Mun. So I designed a stacked lander/orbiter to grab both contracts at once. Unfortunately, the game did not recognize the stacked vessels as two separate vehicles even after they had undocked, one had landed, returned and re-docked. Very frustrating.

Anyways, I'm waiting for an orbital alignment to return to Duna and pick up my stranded tourists. In the mean time, I need to build out my deep space communications network. I designed the Siren to that end - it is a flying antenna with 8.5 km/s of delta v that can deliver it anywhere in the system.

Spoiler :
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The Siren is a simple design though it could be simpler and cheaper. I like simple but at a certain point all the hassle of trying to fly completely optimal trajectories outweighs the value of simplicity so I tend to overbuild on the propulsion side. The first and second stage can eject it from the Kerbin system quite handily with the xenon left with the full 8.5 km/s to go and do whatever I want. I'm going to snag a bunch of KSO contracts to pay for the initial fleet of satellites and then use that highly capable Xenon system to go push on into deep space.

This is the dual lander stack, called the Mako. It uses three engines on the first stage and two massive drop tanks. The initial design had a huge fairing but it was ugly (like all the stock fairings) and it made the vehicle very unstable. The stripped down vehicle flies much better and actually performs better due to the missing weight of the fairing.

Spoiler :
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The transit stage uses a single NERVA and a tapered main tank surrounded by a cluster of drop tanks. I took inspiration from real life second stages that tend to cluster COPV's around the fustrum aft end.
Spoiler :
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Delta II Stage 2 - with the full stack in the background


It turns out that I massively overbuilt the cruise stage and underbuilt the lander. I can get the whole stack to and from the moon with the cruise stage without even dropping the drop tanks. The lander, on the other hand, has to be delivered to a low 75x75 km Mun orbit to have a hope of getting down and back up along with very careful flying. Here is the trans-Mun injection burn of the stack:
Spoiler :
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Here they are at separation in low Mun orbit:
Spoiler :
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Here is the one-astronaut lander on the surface inside a crater:
Spoiler :
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The stack can house 3 astronauts in theory but the Kerbin return ship only supports 2 so I limited the mission to that. For landing, the cruise stage dumps all of the drop tanks, at which point it's a 2-man can, a heat shield and some parachutes. This is by far one of the most wasteful designs I've made as far as re-usability goes. However, the drop tanks on the launcher are fully parachuted and fall off very early in flight so I believe they survived to be retrieved.
 
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Dude that docking bug sounds like a real pain in the butt. Are you going to go through the trouble of editing your way out of it?

Wow I just found an easy solution :scan:

THE UNDOCKINATOR

At first I wasn't sure if I installed the mod right because the icon doesn't show up properly and when I first clicked it I got a message about no docked docking ports existing. But I pressed F9, tried again, and.. an undocking interface came up and allowed me to undock my lander! I think I got lucky there, I am pretty sure my quicksave was before I clicked "undock" and the option disappeared, but when I first loaded up my game it was already after I had done that, so the save was F'd and not even the undockinator could have saved me

So all hail the undockinator.. (but in some situations it's not going to work)

and the mission continues
 
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It's been almost 24 hours so I'm going to assume I can post here again-

I went after that docking mission again with cheap automated probes. For my first launcher design for this mission I decided to try and emulate American launchers which use solid propellant kick stages for final orbital insertion. The resulting design (you can see it to the left of the docking vehicle) was hard to fly. It worked fine but it was tall and lanky and noodled through the air. I didn't want to mess with parallel stages so I gave up on it altogether.

Spoiler :
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I replaced it with a new launcher that is based on the Russian Proton rocket. This one was much easier to fly and I was able to accomplish the docking mission. I then promptly crashed them into the Mun to remove the debris.

Spoiler :
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Proton for reference:
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Second stage pushes it onward:
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Success!
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So I also decided to send a rover with a pilot to Duna to rescue the tourists. The game will not let you launch an astronaut in a rover seat so I had to add a detachable capsule to the top of the stack to house him during launch. I also decided to add a big antenna, solar panels and batteries to the capsule so that after it was detached it could serve as a relay:

Spoiler :

Here it is with the capsule-relay still attached for the trans-Duna injection. I brought it this far to give it some extra distance from Kerbin to increase its utility.
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And here is the back end of the stage with the clustered drop tanks:

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Here's the stage shortly after I put the pilot in the driver's seat but before I dropped the capsule-relay:
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Here is the stage breaking apart for Duna-entry:
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Here's the inflated heat shield:
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The site won't let me attach any more images, but I landed about 3.2 km from the lander. The rover proved to be quite stable (but I added I-Beams to serve as bumpers to prevent tipping) and I got there without trouble.

The trouble I did have was that I realized that even with a pilot, I still could not operate the tourists lander because the 4-person module has not controls and the antenna is still broken. :mad:
 

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Yeah that or docking with it by dropping a module directly on top (where the docking port is). I'm extremely frustrated - engineers should be able to fix a simple whip antenna. It's really dumb that all they can do is fix flat tires and repack parachutes.

I actually made things worse because I forgot all about the fact that engineers can't fix antennas and sent a second ship over with a pilot and an engineer to go and fix the antenna. Literally as I touched down I remembered the engineer was useless. I have ragequit that game for the moment, installed a ton of mods and started a new game.
 
Hey I have an idea for you. What if you build a rover that has a detachable grabbing unit. So, basically just a grabbing unit you can undock or whatever. Attach an antenna right to the grabbing unit. Then drive up to the ship you're trying to rescue with the rover, attach the grabbing unit, then undock it. The result will be that your ship is going to have a new antenna attached. It's going to have a dangly thing too, so I'm not sure how well that's going to work, but it might be enough to get you into orbit. From there you can dock to the ship and push it with a tug.

It might make sense to have 2 such grabbing units, so that you can attach a second one to the other side of your lander. For balance and/or just in case one gets busted again or something
 
Oooh that's a great idea. I wonder if the antenna would actually work though. I'm kind of nervous to even try given how much effort would go into it. I'll have to run some pad tests.
 
The detachable grabbing unit seems to do the exact same thing to ships as a docking port, in terms of being connected to something else at least. I noticed that as I was going through my Jool mission and attached an expansion module to an asteroid that had a refinery already attached to it elsewhere. I realized that the whole thing essentially functions as one big ship, and as a consequence that you can attach anything to a ship, even if it doesn't have a docking port.. but.. it might not look great.

For testing just put down a simple ship with everything but an antenna on the launchpad. That should work I think

A couple days ago I technically wrapped up project ZEUS. I now have 15 relay satellites orbiting the 5 moons, and Valentina landed on all of the moons in the same lander. There was a weird glitch on the last moon and I lost 3 of the engines on the lander and barely made it out of that place alive.. so that lander is no longer going to be used for manned landings. But Valentina is ready to go home so whatever. The new pilot that's here to relieve her is going to have to wait for a new lander to arrive (or maybe a spaceplane or spacesubmarine)

So even though the mission is complete, there is still stuff to do. I still have a fuel refinery orbiting Jool with two engineers on board that needs fuel so it can move. I also have a science station there with a scientist on it, and 8 probes that I intend to launch into Laythe and Jool. And there's an automated lander attached to an interplanetary tug that needs fuel that's orbiting Jool elsewhere. And Valentina and one of the engineers are probably going home, so...

So I had to time things such that the asteroid catcher would take the last of the fuel from the asteroid, so it could fly out and grab a 3rd one. And somehow without real planning that's what happened.

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1928 ton asteroid captured. 1697 tons of ore making its way to the Jool system

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The one downside is that all this takes a while. I think in this case a 12 year journey to depart the Jool system, grab the asteroid, and return. But the little guys don't seem to mind and neither do I

edit: I just noticed that you can't see my guys anymore. So maybe the grappling hook doesn't quite make things "exactly the same as docking". My guys are definitely in there though, I just checked. So definitely run comprehensive tests before you send any more rovers
 
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I would really like to see your launch stacks for these. Are the orange tanks lifted as one piece or docked in orbit? I find docking to be a massive PITA. The rendevouz itself is easy and fun but the physical docking is infuriating. I always forget to turn off SAS (it refuses to dock if both ships have SAS engaged for me and fails 50% of the time if one ship has it on) and I also forgot about the 'chase' camera angle that you should use.

Also, why are your NERVAs at such a high cant angle? You're eating pretty large cosine losses with them arranged like that.

How do you find your energy generation situation while you are mining/refining fuel? I find that the miners are absolute energy hogs and even as far out as Duna I have trouble staying power positive.
 
I would really like to see your launch stacks for these. Are the orange tanks lifted as one piece or docked in orbit?

The 13 orange tanks make up my standard interplanetary tug design. It is usually made up of 14 orange tanks and all lifted up in one go. (The fuel refinery/asteroid catcher version has 13 orange tanks to make room for all that refinery stuff)

I looked around and don't see any lifter screenshots for any of those launches. That's too bad because from what I remember it's a bit of a fun (if bit slow) launch. I will put one on the launchpad and take some screenshots later

For now I am VERY VERY happy because I ran into another bug.. or rather because I figured out how to fix it.. Some asteroids will change shapes as you reload your game. This sucks because if you are attached to that asteroid, it will eat you. I was heading back to Jool with my 3rd asteroid when this is what happened to me.

Took me days to figure out that it was a bug with the way the asteroid ID or seed is determined for the asteroid. I came across it a couple times during research earlier but didn't really take it in properly I guess. Turns out if the asteroid ID is too large, it will convert it to scientific notation, which somehow forces the game to create a new asteroid ID, which implies a new seed, which changes the shape.. or something like that. Anyway, I had to keep reloading my game until I could undock both of my ships. It took a LONG time. Once they were undocked I edited my quicksave.sfs file, found the asteroid, and changed it's ID to a much smaller number. Then I reloaded and docked up my ships, and then reloaded a couple times to make sure the shape is stable, and.. so far it appears to be. But geez that was annoying. Latest thread on it I found was from Jan 20, people were saying it's going to get fixed in the next big update.. Def. watch out for that when you're about to dock to asteroids and back up your save file

Also, why are your NERVAs at such a high cant angle? You're eating pretty large cosine losses with them arranged like that.

It's so that I can grab the biggest possible asteroids and pull on them without some or all of the exhaust hitting the asteroid.

How do you find your energy generation situation while you are mining/refining fuel? I find that the miners are absolute energy hogs and even as far out as Duna I have trouble staying power positive.

My fuel refinery ships have a lot of batteries, and enough solar panels, but if I designed them again I would probably use more. I only end up sometimes getting negative electricity flow, and that's when I'm both mining and refining and the sun is angled weird. But it's so slight it usually allows me to operate for a long period of time anyway. The new attachment that I attach to every single asteroid now has more batteries and solar panels, and I attach it to the other side of the asteroid, so now electricity supply is never a problem when I'm mining or producing fuel

edit: well this is just so damn frustrating... i had such a nice intercept with Jool for my asteroid, and since my fix relied on using an older save file, I now i have to mine it, get fuel, and redo all the maneuvers. I can't even figure them out for anything near an acceptable orbit. I remember spending a lot of time perfecting that, and now it's all for nothing and it seems like I can't even replicate it. This game really gives you the best feelings but also the worst

This is a screenshot of what I'd use to get an asteroid catcher/fuel refinery into orbit

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The whole thing is almost exactly 2,000 tons. I should have taken a screenshot of my 2,500 ton launch setup for the HERA mission, it's slightly more elaborate. Both designs are stable, but you have to be careful to perform each action properly during launch. If you don't make any mistakes it's easy to get into orbit
 
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Good news everyone! I finally managed to build my own spaceplane that is capable of getting into orbit and is thus a SSTO!

I've been at this for a while now and could never figure out a design that would work. This works so I'm sticking to it no matter how curious it might look. If you ask me it looks badass

I present.. CRONUS

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This is a proof of concept prototype. I need to give it power generation and storage capabilities, and I also have plans to make it so it can mine and refuel.... but... we'll see how well that goes

The plan is to send this thing to Laythe.. and I think I have to give it VTOL capabilities as well so that I can land on those tiny islands. Also have no idea how to do that yet, but one step at a time..
 
So does hitting asteroids with your rocket plumes cause problems or something? Does it cause the asteroid to move? That would be silly.

I hope when you add power generation to your ship that it doesn't break your Delta-V budget. I find with every SSTO craft I've made that you end up sweating every single kilogram. :(

I wouldn't worry about VTOL for Laythe. Sure the islands are small but they are not all that small. Though really I guess it comes down to how good your piloting skills are. The way I have always dealt with landing aircraft is I just put a ton of parachutes on them. Then when I want to land, I come in slow, cut the engines, deploy the chutes and come down on the landing gear. For low-atmosphere worlds you can add a set of tiny retrorockets on the bottom to give you a bit of margin on your landing speed. I do not have the patience to learn how to land the proper way.
 
So does hitting asteroids with your rocket plumes cause problems or something? Does it cause the asteroid to move? That would be silly.

I hope when you add power generation to your ship that it doesn't break your Delta-V budget. I find with every SSTO craft I've made that you end up sweating every single kilogram. :(

I wouldn't worry about VTOL for Laythe. Sure the islands are small but they are not all that small. Though really I guess it comes down to how good your piloting skills are. The way I have always dealt with landing aircraft is I just put a ton of parachutes on them. Then when I want to land, I come in slow, cut the engines, deploy the chutes and come down on the landing gear. For low-atmosphere worlds you can add a set of tiny retrorockets on the bottom to give you a bit of margin on your landing speed. I do not have the patience to learn how to land the proper way.

Maybe I don't need VTOL, you're right, but my plane is rather bulky, and Laythe doesn't have much flat ground. I want to visit all the islands in this thing, so I might need some sort of at least semi-VTOL setup. I'm going to play around with it tonight.

As for the rocket plumes hitting the asteroid, if that happens it severely compromises the efficiency of your thrust. Wouldn't it essentially mean that whatever thrust you're applying is also moving the asteroid in the opposite direction? Or say only the engines on one side have exhaust hitting the rocket, it'll put the whole comet into a spin.
 
If you're a great pilot, the plane doesn't even need to be engineered as able to land "properly" - simply attach an engine to force its nose up to allow for easier stall landing. Well, I can't speak for its efficacy; that's dependent on your design, but it's loads simpler than VTOL anyway
 
Maybe I don't need VTOL, you're right, but my plane is rather bulky, and Laythe doesn't have much flat ground. I want to visit all the islands in this thing, so I might need some sort of at least semi-VTOL setup. I'm going to play around with it tonight.

As for the rocket plumes hitting the asteroid, if that happens it severely compromises the efficiency of your thrust. Wouldn't it essentially mean that whatever thrust you're applying is also moving the asteroid in the opposite direction? Or say only the engines on one side have exhaust hitting the rocket, it'll put the whole comet into a spin.
I'm not sure how the game engine handles the physics of plume impingement on asteroids to be honest. But in real life, the over-expanded exhaust of some rocket engines touching the surface won't have a huge impact other than kicking up a ton of regolith. Sure, you can move the asteroid when attached because of the net thrust of the engines but by the time the gas actually hits the asteroid its so diffuse that it won't do much thrusting yourself. Now this is not the case for real life spacecraft which do have to be clear of rocket plumes because they are small and can get pushed around (and contaminated by toxic rocket fuels) but an asteroid won't be bothered. But again, I don't know how the game handles these interactions. I know that plumes will push spacecraft around in the game but not sure about the asteroids. I assume nothing would happen but could be wrong.
Hmmm I'll try that, thanks!

I can't use parachutes either, because I'm not planning on bringing an engineer with me
Only land it once? Alternatively, carry redundant sets of parachutes for multiple landings.
 
Hmm I did a bunch of research when designing my 2nd generation asteroid tug, and most people who have done it before recommended doing just what I did, and making sure that the engines face away from the asteroid. I actually haven't tested what would happen if the engines were pointing directly at the asteroid, but doesn't it make sense that it would severely hinder the thrust? I don't think I've ever seen a spacecraft that's design in a way that has the engines pointing at another part of the ship. Maybe I got my physics all mixed up, and I'm not great at physics to begin with, but thrust would be generated to push you forward, but doesn't each action have an equivalent reaction in the other direction? So if all of your exhaust hits a wall, doesn't that push the wall in the other direction as well? Even if the backwards push is 50% or 20% of the forwards push, it seems it would still be a problem.

I have a problem with my space plane. I used hyperedit to put it into orbit around Laythe to test the design. When it enters the atmosphere it just spins around like a drunk Russian. And I can never regain control. It just falls into the ocean spinning around, even if I turn the engines on, SAS, try to orient myself, etc. It handles well when I'm taking off from Kerbin, and seems to be maneuverable enough, but it's not maneuverable at all when I'm trying to land on Laythe. So something is up with my design, but I'm not sure what.
 
The thrust is determined by the force on the thrust structure. That force is generated by the gas coming out of the back end, but once that gas comes out it has no effect on the rocket. Now if it hits the asteroid, it can push it away which will detract a bit from your overall thrust. But by the time the gas hits the asteroid it's so diffuse (and traveling in nearly all directions - not just straight at the asteroid) that the net effect will be very negligible. But that's the real world, again I don't know what the game would do. And I'd also point out the astronomically high mass of the asteroid is such that makes that diffuse exhaust even more negligible as far as net effect.

The biggest thing though is that once that gas leaves the nozzle it is no longer directed in a stream - the molecules start going every which way as they spread out and collide with each other. So the thrust the asteroid would feel would be tiny - especially compared to its mass.

I'm not sure what is going on with your Laythe plane though. Is it still stable if you re-enter Kerbin's atmosphere?
 
Hmm that's all very interesting. I presume that in the game the exhaust hitting the asteroid makes a big difference, because people who design their tugs to pull asteroids (that work) all say (from what I've seen) to point the engines away from the asteroid.

What would happen in this real-life scenario? A rocket with an enclosed space around the engine (assuming that the enclosure is indestructible)

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I always assumed that ship wouldn't move at all. So when I found out people angle their engines the way they do, it all made sense to me in my head. "Well, obviously". But now I'm confused again.

I haven't tried getting my spaceplane down from Kerbin's orbit back down into the atmosphere. I should try that.. I suspect the same thing will happen, but I have no idea how to fix that
 
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