Kerbal Space Program
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hobbsyoyo
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SSTO MOFOS
Great success!
INTRODUCING LVL-1B
INTRODUCING LVL-1B
Let's start with the unique Kerbal Deployment System(TM*)
Spoiler :
Because of the quad-coupler on the bottom, I couldn't just put my ladder straight down the side. So I had to make this odd little thing to put the ladders at an angle to go around the engine mount. That is a picture of a test version that has 4 LV-T30 engines on it but I tested it and it didn't work (it doesn't have the jets attached yet as I wanted to test the ladder system).
Also, I found that when a Kerbal does and EVA, he can repack parachutes. So if I just place the parachutes around the top, I can right click on them and repack them for reuse if my Kerbal is on the ladder.
This is another test version that also lacks all 5 rocket engines.
Spoiler :
It has the full compliment of 16 jet engines though and this version got to 900m/s and about 18000m on jet engines alone. Unfortunately, I pushed this flight too far and the engines flamed out a split second before I activated my rockets and I went into a spin. Re-launches proved that 2 mainsails do not produce enough thrust on their own to get this thing into orbit. They do provide a TWR of over 1, however, you have to burn them too long and thus run out of fuel. Adding 3 more LV-T30's proved to provide the right combination of thrust and fuel efficiency to get this honking love machine to orbit.
Here's a close up of the engines:
Spoiler :
Here's some pics I took on orbit and proof of successful orbital insertion:
Spoiler :
Here it is coming in for a landing:
Spoiler :
The LVL-1b clocks in at 169tons and 221 parts.
There are a couple of things I learned while building this:
Turbojet engines are buggy and require a lot of electricity to run. That was why earlier 16 turbojet models failed to throttle up, their propensity to hog juice and their buggy nature prevented them from throttling. Adding more electrical systems does not always work. To throttle up, I had to momentarily fire the mainsails to get enough juice to the jets, then turn off the mainsails. Also, even when SAS is turned off and nothing is draining power, the jets (due to their bugs) will continue to suck electricity. You can see from the picture of it landing how close I came to powering off - even though I have an RTG attached. Production models will have solar back up.
To make maximum use of the jets, ascend very slowly. Basically, watch your prograde marker and keep it right above the horizon. You want to pick up all of the speed you can before you hit maximum altitude and the threat of flameout.
Turbojets don't produce anywhere near their maximum thrust of 250kN until close to 1000m/s. This means you are in for a very long, slow flight. It took me about 15 minutes to get to orbit. Also, you have to really watch your prograde marker and your altitude to make sure you are still climbing, but not climbing too fast. It was a bit of a challenge to fly, particularly an early 8 turbojet engine model. However, adding the extra 8 turbojets added more mass and more thrust vectoring, which actually made it much easier to control and stopped it from spinning.
Don't push it - once you are over 10000m, you have to keep a constant eye on your air intake readings. It becomes a challenge to fly at this point not because it's unstable (it's actually better stability-wise than most of my asparagus designs) but because you have to watch so many damned meters constantly. Above 10km, you start losing your air intake rate. However, once you push through 300m/s, the engines really start putting out thrust and you begin to accelerate faster. This forces more air into the intakes, which reverses the decline in air intake rate. You hit a sweet spot where you can really pick up steam at high altitude - as long as you climb very slowly. If you don't watch it, you'll go above your max altitude and flame out just when things get going.
With the extra rocket engines, the final model got up to about 500m/s and 14km before I switched to rockets. I could've pushed it harder but I didn't want to waste another 15minutes of my life in a failure. However, when I activated the rockets, it pushed my velocity up so fast that the intake rate shot back up for a while and I was able to enjoy thrust from all 5 rockets and 16jets simultaneously for about 30 seconds or so. I was still fairly low in the atmosphere, so I started glowing red hot. It was freaking cool!!!!
Oh and you have to be mindful of your fuel mix with jet/rocket hybrids. Jets don't use oxidizer, so they only drain fuel out of your rocket tanks, leaving some oxidizer left over. I compensated by adding a few jet fuel parts which don't contain oxidizer to begin with and this canceled out the problem. As you can see, I basically wound up without any excess oxidizer, which means I stumbled on a really good fuel mix.
There is very little room for error on Kerbin SSTO missions. I got to a very minimal orbit with just enough fuel to deorbit and then slow down for proper chute deployment. This was an unmanned flight and I'm not sure if Kerbalnauts have weight. If so, no fatties will be allowed on this rocket, lol.
Oh and because of the way I set up my fuel lines, the jet engine tanks drained out first. What this meant is that to use them for landing (which would be much more efficient than rockets), I'd have to manually pump fuel around which is imprecise and tedious when you have to do it for 16 jet fuel tanks.
However, landings on Laythe won't have this problem as I'll be descending from orbit fully-fueled.I have to add more parachutes to the final model so I don't have to throttle up so much and because a fully-fueled landing on Laythe is going to put a ton of stress on my chutes.
I have to add more power systems to offset the jet engine bugs.
I have to add a couple of small RCS tanks.
None of those things will add appreciable weight, I think. I'm going to go with the smallest RCS tanks possible because I can't afford a bigger tank unfortunately. Also, docking with my station after lift-off from Laythe will mean that I'm nearly empty on fuel, so I won't need as much RCS to maneuver. The plan is also to have my interplanetary booster stage have lots of it's own RCS fuel so that docking with the station after travelling from Kerbin won't be an issue either. If it comes down to it and I don't have enough RCS fuel, (I'll do unmanned tests at Laythe first so no one dies) then I'll just develop a small orbital tug to travel from the station to the lander and bring it in to dock.
This is honestly the biggest engineering challenge I've done yet in KSP. It doesn't look like much but SSTO is a huge challenge; there's a reason why no one has done it in real life.
I also realize I've waaaay overengineered this thing. With 20% less gravity and atmosphere, I won't need such a powerful rocket on Laythe, but I can't test for that easily so I set a goal of SSTO off Kerbin to prove the validity of the design. That extra 20% of effort translates into such a bigger rocket that it's not even funny. In the aerospace field, we talk about the 'tyranny of the rocket equation'.
The only thing I'm worried about is the thinner air on Laythe will make me have to reinvent my flight profile. Oh well, I'm sure it'll work out, if anything, I'll just have to burn my rockets a bit longer - but because you need less deltaV to get into orbit there it should cancel out.
* All Warpus Trademark Violators Will Be PERSECUTED
Nah if anyone wants any more info on the rocket just let me know.
Attachments
I guess SSTO is possible in KSP, I was doubtful myself. Good job!
I've been having some fun with recoverable craft (I put parachutes on my empty booster stages that fire when they stage-separate) and with a cowboy-style orbital re-entry unit. My two kerbals clinging to the ladder died when the parachute broke, though, giving me my first two casualties of my post-0.20 space program.
I've been having some fun with recoverable craft (I put parachutes on my empty booster stages that fire when they stage-separate) and with a cowboy-style orbital re-entry unit. My two kerbals clinging to the ladder died when the parachute broke, though, giving me my first two casualties of my post-0.20 space program.
hobbsyoyo
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Thanks. There are a lot of ways to do SSTO and mine certainly isn't the best. My list of objectives for this thing (had to bring at least 3 Kerbals down to the surface or back up, fully reusable, had to be able to dock, has to have RCS, has to have long-term power systems, has to be able to be controlled remotely, etc) really hampered me. If I just wanted a simple 1-Kerbal SSTO it would have been much easier. I could have also taken the space plane route but I freaking hate spaceplanes in this game so far.
I have to admit though I feel pretty gimmicky for using jet engines; I just don't see any other way of doing SSTO and meeting my objectives. As it turns out, the 4-man hitchiker can is lighter than a capsule with 1 more passenger so that will save me some trips when staffing my surface base.
Did you try using the special rocket seat to hold your guys? Why put them on a ladder? Also, I've seen guys make boxes with girders around ladders (pre-rocket seat days) to hold their guys on the rocket.
I had four of the seats but they were too close to the solar panels and my guys couldn't board them. I think. Or, you can't go from EVA rocket pack directly to the seat without first being on a ladder or something. Long story short, I couldn't board.
However, they were hanging on decently well through the reentry, it's just that the parachute line broke on the manned trial when it was fine on the unmanned. I had to manually deploy it, so I hope I didn't double-click and hit the immediate release button.
hobbsyoyo
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I'm at a crossroads....I don't know whether or not I should build a massive launcher to send my LVL-1b to Laythe or if I should put the LVL-1b in LKO, refuel it, then dock it with a cruise stage to send it to Laythe (where it will probably have to refuel again).
On the one hand, having a massive launcher means I'll only have to launch once and be done with it. However, this is incredibly hard to do as big rockets tend to fall apart.
On the other hand, launching everything separate is relatively easy. However, it's time consuming and will require 3-4 launches per lander I send to Laythe. Also, I'll have to design a cruise stage to go with the LVL-1B.
What do you all think I should do?
I started design work on a mega launcher and I got the core stage to perform well. Then I got 2 side boosters to operate well after much trial and error and then...they didn't work. What's really frustrating about mega rockets is the game is so finicky that you can have a flawless launch in one go and then everything falls apart in the next. I don't know what to do.
On the one hand, having a massive launcher means I'll only have to launch once and be done with it. However, this is incredibly hard to do as big rockets tend to fall apart.
On the other hand, launching everything separate is relatively easy. However, it's time consuming and will require 3-4 launches per lander I send to Laythe. Also, I'll have to design a cruise stage to go with the LVL-1B.
What do you all think I should do?
I started design work on a mega launcher and I got the core stage to perform well. Then I got 2 side boosters to operate well after much trial and error and then...they didn't work. What's really frustrating about mega rockets is the game is so finicky that you can have a flawless launch in one go and then everything falls apart in the next. I don't know what to do.
Spoiler :
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warpus
Sommerswerd asked me to change this
I sent up my Laythe rescue lander into orbit, docked with one of my usual tankers, and used the tanker to push it to Laythe, sending another tanker along with it for extra fuel. My Laythe lander is larger than yours hobbs though, I had issues getting it into orbit from Kerbin even.
Landing my Laythe lander on the north pole, beside the guys I need to rescue wasn't easy either. But I succeeded! Now I need to ferry the poor guys 1 by 1, 10km across the frozen surface, to the rescue lander. I got 1 of them in, 2 more to go.
I will post pics of the whole operation once I either get them in orbit or kill them trying. I'm still not fully sure if my Laythe lander will get me into orbit - I think it will, but who knows. I had to use a bit of the fuel from its central core to help me break during descent so that my parachutes would open relatively safely and not either flip my lander upside down or just tear parts of it off. Just a bit of that fuel mind you, but I really wanted all the fuel intact. My landing engines worked almost to perfection - 5% more fuel there and it would have worked perfectly and I wouldn't have had to use my central core engine to help.
Landing my Laythe lander on the north pole, beside the guys I need to rescue wasn't easy either. But I succeeded! Now I need to ferry the poor guys 1 by 1, 10km across the frozen surface, to the rescue lander. I got 1 of them in, 2 more to go.
I will post pics of the whole operation once I either get them in orbit or kill them trying. I'm still not fully sure if my Laythe lander will get me into orbit - I think it will, but who knows. I had to use a bit of the fuel from its central core to help me break during descent so that my parachutes would open relatively safely and not either flip my lander upside down or just tear parts of it off. Just a bit of that fuel mind you, but I really wanted all the fuel intact. My landing engines worked almost to perfection - 5% more fuel there and it would have worked perfectly and I wouldn't have had to use my central core engine to help.
hobbsyoyo
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I really want to see your lander and I would like to,see how it turns out. Your lander is more than 165tons? Ouch!
I am going to do some math when I get home and design a new lander. I can't design a booster capable of putting it into orbit, much less getting it to Laythe. And launching it SSTO, refueling and getting a cruise stage up there is just too much of a hassle.
I am going to do some math when I get home and design a new lander. I can't design a booster capable of putting it into orbit, much less getting it to Laythe. And launching it SSTO, refueling and getting a cruise stage up there is just too much of a hassle.
warpus
Sommerswerd asked me to change this
Hmm I'm not sure how heavy it is. It just looks bigger than yours. I have no concept of how much things weigh in this game, so I'd have to check 
My 2nd guy is on his way to the lander, but it's annoying walking across 10km, even with x2 on and my hand on the shift key. 9.5km away! sigh
edit: looking at it again, I think mine is smaller. It just looks bulkier with the landing stage engines, it's why it was such a hassle launching it into orbit, not to mention pushing it to Laythe
My 2nd guy is on his way to the lander, but it's annoying walking across 10km, even with x2 on and my hand on the shift key. 9.5km away! sigh
edit: looking at it again, I think mine is smaller. It just looks bulkier with the landing stage engines, it's why it was such a hassle launching it into orbit, not to mention pushing it to Laythe
Last time, I left a kerbonaut stranded around Moho eating algae paste and drinking his recycled urine for something like 300 days. It's about time we got him back. For once I took some screenshots:
The assembled S-007 (Voyager) leaves Kerbin orbit towards Moho with a much more efficient insertion burn than the first time.
Braking into Moho, spent six booster tanks on the way over. Still think I have enough fuel though.
Crud, they are in opposite orbits and the inclinations are all off. I'll just have to use the Crotch Rocket's remaining fuel to correct that--we must preserve the fuel on Voyager for the return trip!
Close enough, time to space walk over!
Freedom! Freedom!!!
I don't have as many images of the return burn because I had to do it a couple times. I found the trick is not to immediately line up the planets and just go, but rather to get out of Moho's gravity well (but essentially stay close to that orbit) when you are at Kerbin's inclination, then do an inclination correction burn so you don't need some insane 2000 m/s delta-V to pull off the maneuver. Then, I waited for the optimal planet placement and burned my way home.
Coming in! Fuel tanks are running out!
Crud, just a little short... but I still have some RCS fuel. Time to jettison the useless base and RCS-brake into orbit. Not enough fuel left to aerobrake and this craft doesn't have parachutes.
Success, though, the RCS fuel is enough to get me into orbit! Or, at least a third of it, but that has my crew and that's all I care about. I'll need to send up another propulsion module, redock it, and then get into an appropriate orbit and change the crew. That can wait for another day, though, at least they have good food in the hab module!
Side note: Annand Kerman (I think that was his name) spent a grand total of 488 days alone in space before being rescued. Add the return trip and he's easily around 550 or more.
The assembled S-007 (Voyager) leaves Kerbin orbit towards Moho with a much more efficient insertion burn than the first time.
Spoiler :
Braking into Moho, spent six booster tanks on the way over. Still think I have enough fuel though.
Spoiler :
Crud, they are in opposite orbits and the inclinations are all off. I'll just have to use the Crotch Rocket's remaining fuel to correct that--we must preserve the fuel on Voyager for the return trip!
Spoiler :
Close enough, time to space walk over!
Spoiler :
Freedom! Freedom!!!
Spoiler :
I don't have as many images of the return burn because I had to do it a couple times. I found the trick is not to immediately line up the planets and just go, but rather to get out of Moho's gravity well (but essentially stay close to that orbit) when you are at Kerbin's inclination, then do an inclination correction burn so you don't need some insane 2000 m/s delta-V to pull off the maneuver. Then, I waited for the optimal planet placement and burned my way home.
Coming in! Fuel tanks are running out!
Spoiler :
Crud, just a little short... but I still have some RCS fuel. Time to jettison the useless base and RCS-brake into orbit. Not enough fuel left to aerobrake and this craft doesn't have parachutes.
Spoiler :
Success, though, the RCS fuel is enough to get me into orbit! Or, at least a third of it, but that has my crew and that's all I care about. I'll need to send up another propulsion module, redock it, and then get into an appropriate orbit and change the crew. That can wait for another day, though, at least they have good food in the hab module!
Spoiler :
Side note: Annand Kerman (I think that was his name) spent a grand total of 488 days alone in space before being rescued. Add the return trip and he's easily around 550 or more.
Attachments
warpus
Sommerswerd asked me to change this
Success! My 3 guys are currently in orbit around Laythe 
My lander didn't behave as expected and the design turned out to be crap in many respects, but it worked well enough to get me into orbit with fuel to spare.
Here's my mission profile:
The Cech lander sitting on top of its launcher, with 3 accidental astronauts on board. This was supposed to be empty! This happened every time I re-edited my ship in the VAB, even though I'd remove all dudes and save. Ah well. I had to obviously re-launch this, but you can see what my launcher and rescue lander look like. I ended up needing to add 32 solid fuel boosters to get into orbit, and even then I needed help from my aerospike engines as well. This had a lot of stability issues, leading to carefully placed struts all over the place.
Once in orbit I docked with a Mata tanker and.. tried to burn for Jool. As you can see my design wasn't very well thought out. I'm still using my main launcher core here, in what I call the hobbsyoyo maneuver. Incredibly unstable, but I wasn't going to waste that fuel.
Once that fuel ran out, the tanker took over. This was better, but still unstable. Very wobbly. And eventually it was clear I wouldn't have enough thrust to finish burning in one go.. I had to stop burning, make an orbit around Kerbin, and then continue.
I didn't think it would work, but I got that encounter with Jool. Somehow! My trajectory looked way off when I was burning, but then magically a wild encounter appeared. It was a pretty good one too. I went back to the launch pad, sent another Mata tanker into orbit, and then sent it towards Jool as well. I fixed both trajectories once leaving Kerbin's SOI and eventually plunged both ships straight into Laythe's atmosphere, bypassing Jool altogether. Thanks for that tip hobbs! Would have never thought to do that.
Next I had to get my lander in a polar orbit, since my guys were stuck on the north polar ice cap. I used up all the fuel I had left in the tanker and I wasn't anywhere near a polar orbit.. So I fired up the landing engines in my lander and.. not very efficient and not much fuel there! That worried me - would they be good enough to help me land?
Either way, I had to fire up my aerospike engines and use up most of the fuel in those tanks to get into a polar orbit. Once there, it was a question of docking with the tanker I sent along with this mission and refuel.. nope, not enough fuel. Fortunately enough I had another tanker in a low orbit around Jool. That was supposed to be "going home fuel", but I needed it now. After docking and refuelling my lander was finally full, and my tanker had some fuel left.
Now it was going to get tricky.. I wanted to land with most of my fuel reserves intact, maximizing my chance of getting back into orbit as much as I could.. so I remained docked and used the tanker to burn retrograde until I got this
Goal was to let the atmosphere slow me down most of the way.. and then use my landing engines to slow down enough for the parachutes to kick in.. after that I'd need my landing engines again to slow down enough so that I would be going slow enough for a non-fatal landing.
Surprisingly enough my initial entry was near perfect.. but the landing had to be attempted several times anyway - this whole maneuver of me using the tanker to slow down was repeated maybe 7-8 times
I totally didn't think any of this was going to work, but.. somehow my aim was much better than expected
This is a photo from a failed landing, but this usually happened at some point - the tanker would fly by me.. towards those poor guys on the surface. It'd never hit me or them mind you, but it always startled me... as it was usually pretty damn close... and I was trying to concentrate on the landing
The failed landings were failed landings because the chutes opened up when I was going too fast.. and a couple times I ran out of fuel in my landing engines and crashed. The chutes just wouldn't cooperate - I would slow down to 90m/s and they'd still flip my lander upside down.. and some of them would tear right off. I almost gave up - I thought my lander design was flawed in some way.
So then in one landing I slowed down to 70-80m/s and my chutes opened up properly! But a bunch of my landing fuel was gone. So I quickly turned on my central engine - which I really didn't want to use, since it was supposed to be the last engine I'd use to get into orbit. The aerospike engines I had to turn on one by one, so I couldn't do that, unless I turned them on much earlier in the descent. So central engine it was (a T30)
I burned and burned and made sure my landing was as soft as possible.. my landing fuel was almost gone
And then.. TOUCHDOWN!
As you can see my landing fuel is almost all gone. I transferred the remains into my main core, which was now unfortunately partially depleted. The whole core holds 2,800 units of fuel - I ended up with about 2,550 after the fuel transfer from the landing stage. That RCS tank by the way is only about 7% full - I drained most of it before attempting my landing. I figured I would make the lander as light as possible.
I landed 10.1km from my 3 guys.. so.. not bad, considering, but I had to walk them over one by one. This took a while, as you can imagine. I almost considered designing and sending over a rover to help..
During one of these walks I decided to zoom out a bit to see what the polar ice cap actually looked like. That's when I realized how lucky I was
Both landers landed right beside a a body of open water. The first landing was totally blind - done in near darkness. I assumed that there was ice below me, and nothing but ice, but no.. Somehow my rescue ship didn't end up in the water either (the top one). Phew..
Once my 3 guys were safely in my Cech rescue vehicle, I detached the landing engines and fuel tanks, and was ready to go.. I decided to begin my gravity turn at 7km up.. and.. nope.. the aerospike engines wouldn't cooperate. Any sort of turn in any direction at any time sent the ship spinning out of control... even though I had reaction wheel thingies.. or SAS.. or whatever they were, on each aerospike column. I forgot what I put there, but during testing on Kerbin it seemed to have really helped quite a bit and made my lander maneuverable. Maybe the thinner atmosphere was the problem?
I don't know, but in the end it became clear that a gravity turn was not possible.. So.. I went as high as the aerospike engines took me, detached them, turned on my central core T30 engine, turned sideways and went to work.
Aaaand I started slowing down, big time. Was this engine not powerful enough? crap.. this wasn't looking good.. I was almost back in the atmosphere and here is what the situation looked like
But I kept at it and eventually.. ORBIT! My guys were safe! I even had enough fuel left to circularize.
And that's where I'm at now. The plan now is to send 2 or 3 more tankers, refuel the other ship you see in the picture above, which is Zola - the first ship I sent into the sytem in the first place - it's basically a tanker with external seats on it. Initially this was a backup plan, but it's turned into the return vehicle. So that's how my guys are going home.
I considered sending another lander and making them visit the 2 moons I haven't been to yet - but I realized that they're out of flags! I think anyway. They've been to 3 moons: Laythe, Bop, and Vall, so.. whatever. 0.22 is almost out, so I'm going to send them home. They've been there for 6 years now. Once they're home I'm going to dock them to the space station, and then send a small retrieval ship there to pick them up.
Then they're going to land and get as much Kerbal vagina, beer, and steak as they want. They goddamn deserve it.
This was my all-time favourite set of Kerbal missions so far, this Jool stint. It involved many many launches and the sending of many tankers to the system. Well, maybe 10. maybe 8. I lost track.
And the Laythe retrieval mission, that I've documented here? It was fun and many times I didn't think it was going to work at all.. but it somehow did. It turned out to be a horrible design, but it also lead to these firsts:
- Put together a ship in orbit and sent the whole thing to another planet
- Aerobroke in Laythe's atmosphere without orbiting Jool first
- Used specialized landing engines
I think there's more, but I'm kinda tired and out of it. This has been fun. Thanks for convincing me to land on Laythe hobbsyoyo.. It was probably a stupid idea
but it lead to a lot of fun. I am finishing off the mission in the morning, the rest of the stuff is now routine to me. Send 3 tankers, dock them, refuel, meet up with my guys, make them sit in those external seats, dock with space station, etc. That should take a couple hours, but these 3 guys deserve my attention and I really can't wait for them to land on Kerbin. That will feel awesome.
My lander didn't behave as expected and the design turned out to be crap in many respects, but it worked well enough to get me into orbit with fuel to spare.
Here's my mission profile:
The Cech lander sitting on top of its launcher, with 3 accidental astronauts on board. This was supposed to be empty! This happened every time I re-edited my ship in the VAB, even though I'd remove all dudes and save. Ah well. I had to obviously re-launch this, but you can see what my launcher and rescue lander look like. I ended up needing to add 32 solid fuel boosters to get into orbit, and even then I needed help from my aerospike engines as well. This had a lot of stability issues, leading to carefully placed struts all over the place.
Spoiler :
Once in orbit I docked with a Mata tanker and.. tried to burn for Jool. As you can see my design wasn't very well thought out. I'm still using my main launcher core here, in what I call the hobbsyoyo maneuver. Incredibly unstable, but I wasn't going to waste that fuel.
Spoiler :
Once that fuel ran out, the tanker took over. This was better, but still unstable. Very wobbly. And eventually it was clear I wouldn't have enough thrust to finish burning in one go.. I had to stop burning, make an orbit around Kerbin, and then continue.
Spoiler :
I didn't think it would work, but I got that encounter with Jool. Somehow! My trajectory looked way off when I was burning, but then magically a wild encounter appeared. It was a pretty good one too. I went back to the launch pad, sent another Mata tanker into orbit, and then sent it towards Jool as well. I fixed both trajectories once leaving Kerbin's SOI and eventually plunged both ships straight into Laythe's atmosphere, bypassing Jool altogether. Thanks for that tip hobbs! Would have never thought to do that.
Spoiler :
Next I had to get my lander in a polar orbit, since my guys were stuck on the north polar ice cap. I used up all the fuel I had left in the tanker and I wasn't anywhere near a polar orbit.. So I fired up the landing engines in my lander and.. not very efficient and not much fuel there! That worried me - would they be good enough to help me land?
Either way, I had to fire up my aerospike engines and use up most of the fuel in those tanks to get into a polar orbit. Once there, it was a question of docking with the tanker I sent along with this mission and refuel.. nope, not enough fuel. Fortunately enough I had another tanker in a low orbit around Jool. That was supposed to be "going home fuel", but I needed it now. After docking and refuelling my lander was finally full, and my tanker had some fuel left.
Now it was going to get tricky.. I wanted to land with most of my fuel reserves intact, maximizing my chance of getting back into orbit as much as I could.. so I remained docked and used the tanker to burn retrograde until I got this
Spoiler :
Goal was to let the atmosphere slow me down most of the way.. and then use my landing engines to slow down enough for the parachutes to kick in.. after that I'd need my landing engines again to slow down enough so that I would be going slow enough for a non-fatal landing.
Surprisingly enough my initial entry was near perfect.. but the landing had to be attempted several times anyway - this whole maneuver of me using the tanker to slow down was repeated maybe 7-8 times
I totally didn't think any of this was going to work, but.. somehow my aim was much better than expected
Spoiler :
This is a photo from a failed landing, but this usually happened at some point - the tanker would fly by me.. towards those poor guys on the surface. It'd never hit me or them mind you, but it always startled me... as it was usually pretty damn close... and I was trying to concentrate on the landing
Spoiler :
The failed landings were failed landings because the chutes opened up when I was going too fast.. and a couple times I ran out of fuel in my landing engines and crashed. The chutes just wouldn't cooperate - I would slow down to 90m/s and they'd still flip my lander upside down.. and some of them would tear right off. I almost gave up - I thought my lander design was flawed in some way.
So then in one landing I slowed down to 70-80m/s and my chutes opened up properly! But a bunch of my landing fuel was gone. So I quickly turned on my central engine - which I really didn't want to use, since it was supposed to be the last engine I'd use to get into orbit. The aerospike engines I had to turn on one by one, so I couldn't do that, unless I turned them on much earlier in the descent. So central engine it was (a T30)
I burned and burned and made sure my landing was as soft as possible.. my landing fuel was almost gone
Spoiler :
And then.. TOUCHDOWN!
Spoiler :
As you can see my landing fuel is almost all gone. I transferred the remains into my main core, which was now unfortunately partially depleted. The whole core holds 2,800 units of fuel - I ended up with about 2,550 after the fuel transfer from the landing stage. That RCS tank by the way is only about 7% full - I drained most of it before attempting my landing. I figured I would make the lander as light as possible.
I landed 10.1km from my 3 guys.. so.. not bad, considering, but I had to walk them over one by one. This took a while, as you can imagine. I almost considered designing and sending over a rover to help..
During one of these walks I decided to zoom out a bit to see what the polar ice cap actually looked like. That's when I realized how lucky I was
Spoiler :
Both landers landed right beside a a body of open water. The first landing was totally blind - done in near darkness. I assumed that there was ice below me, and nothing but ice, but no.. Somehow my rescue ship didn't end up in the water either (the top one). Phew..
Once my 3 guys were safely in my Cech rescue vehicle, I detached the landing engines and fuel tanks, and was ready to go.. I decided to begin my gravity turn at 7km up.. and.. nope.. the aerospike engines wouldn't cooperate. Any sort of turn in any direction at any time sent the ship spinning out of control... even though I had reaction wheel thingies.. or SAS.. or whatever they were, on each aerospike column. I forgot what I put there, but during testing on Kerbin it seemed to have really helped quite a bit and made my lander maneuverable. Maybe the thinner atmosphere was the problem?
I don't know, but in the end it became clear that a gravity turn was not possible.. So.. I went as high as the aerospike engines took me, detached them, turned on my central core T30 engine, turned sideways and went to work.
Aaaand I started slowing down, big time. Was this engine not powerful enough? crap.. this wasn't looking good.. I was almost back in the atmosphere and here is what the situation looked like
Spoiler :
But I kept at it and eventually.. ORBIT! My guys were safe! I even had enough fuel left to circularize.
Spoiler :
And that's where I'm at now. The plan now is to send 2 or 3 more tankers, refuel the other ship you see in the picture above, which is Zola - the first ship I sent into the sytem in the first place - it's basically a tanker with external seats on it. Initially this was a backup plan, but it's turned into the return vehicle. So that's how my guys are going home.
I considered sending another lander and making them visit the 2 moons I haven't been to yet - but I realized that they're out of flags! I think anyway. They've been to 3 moons: Laythe, Bop, and Vall, so.. whatever. 0.22 is almost out, so I'm going to send them home. They've been there for 6 years now. Once they're home I'm going to dock them to the space station, and then send a small retrieval ship there to pick them up.
Then they're going to land and get as much Kerbal vagina, beer, and steak as they want. They goddamn deserve it.
This was my all-time favourite set of Kerbal missions so far, this Jool stint. It involved many many launches and the sending of many tankers to the system. Well, maybe 10. maybe 8. I lost track.
And the Laythe retrieval mission, that I've documented here? It was fun and many times I didn't think it was going to work at all.. but it somehow did. It turned out to be a horrible design, but it also lead to these firsts:
- Put together a ship in orbit and sent the whole thing to another planet
- Aerobroke in Laythe's atmosphere without orbiting Jool first
- Used specialized landing engines
I think there's more, but I'm kinda tired and out of it. This has been fun. Thanks for convincing me to land on Laythe hobbsyoyo.. It was probably a stupid idea
but it lead to a lot of fun. I am finishing off the mission in the morning, the rest of the stuff is now routine to me. Send 3 tankers, dock them, refuel, meet up with my guys, make them sit in those external seats, dock with space station, etc. That should take a couple hours, but these 3 guys deserve my attention and I really can't wait for them to land on Kerbin. That will feel awesome.
hobbsyoyo
Deity
- Joined
- Jul 13, 2012
- Messages
- 26,575
Those missions are awesome!
I've never really even been to Moho. I flew by in a probe once and I tried to orbit but I was going like .99c and I couldn't brake enough so it went by like ------------------------------------------------------------------------------------------------------------------------------------------------------------------------> gone.
That's a good trick to use to get out of Moho's orbital inclination Antilogic. I wonder if that uses less fuel than trying to do the inclination burn in Moho's SoI? When you were in Kerbol orbit, did you set Kerbin as your target and use the descending/ascending nodes to correct your inclination? Those markers show when you cross your target's orbit and that's the most efficient place to do an inclination burn, fyi.
Also (and Moho is an exception because of the inclination) it is usually more fuel efficient to do a transfer burn from as low of an orbital altitude as possible. It's called the Oberth effect and basically the same burns will get very different deltaV's depending on the altitude you burn at. A burn at low orbit basically takes the gravitational energy of the planet and it's angular momentum to fuller advantage and gives you a bigger boost than a higher orbit burn. Most efficient of all is doing your entire burn at once (by launching and never stopping off at LKO) but this isn't practical when you have to dock ships. I'd just thought I'd pass that along because I just learned it in class.
lol the hobbsyoyo maneuver --> I'm actually going to have to use that soon
I was having serious issues trying to figure out how to get my LVL-1b into orbit. The main issue isn't actually the mass, it's that because I use 2 mainsails at the bottom, I can't easily attach a decoupler to the base to mount it on a rocket. This means I have to use 2 decouplers and there's no way I've found to be able to link them to a single decoupler. This means I have to use a double-stack main core and that's a ton of stability/symmetry issues with that. I tried it and I couldn't get it to work reliably so instead of trying to reinvent the heavy launcher, I just decided to ditch that idea.
So I tried launching the LVL-1b from the ground by itself and going SSTO to orbit. The problem is that after I added the last few systems to complete it, it takes extreme precision flying to get to orbit. I couldn't do it reliably and since I'd have to send up about 3 of these things and then refuel them and then attach a cruise stage, it's just to much effort. Then I tried the Warpus method and strapped a bunch of SRB's to it (72 big ones). They hurl my vehicle up so far and so fast that I can only use the jet engines for a few seconds before they flame out but then I turn on the rockets and boost it to orbit, no problem. Because of the thinner atmosphere and lesser gravity at Laythe, I'm confident I can SSTO there will little issue.
So anyways, I put a lander into very low LKO (just skimming over the top of the atmosphere) but it still doesn't have RCS fuel which it will need to dock with in Laythe orbit. So I had to build and launch a little RCS tug boat. I'll put up a picture later. Anywho, this thing is a real challenge to fly and dock because it's so little and has so much thrust from it's tiny engines and RCS units. But I managed to dock it and then I built and designed a refueling rig.
Thing is I accidentally massively overbuilt the launcher for my refueling rig. It got to orbit without running out of fuel in the 2 final side booster, which also means the entire central core is fully fueled (asparagus staging) as well as the actual payload of propellant. I don't think I can transfer fuel from the core stage to the payload tanks, so I may have to waste all of that fuel on this first launch (haven't docked yet to see). In any case, all of that extra fuel means I can attach some NERVA's to the core and use the same tanker as my cruise stage with a slight redesign. So the goal for today is to dock the tanker and refuel my lander, then send up another tanker/cruise stage and send it to Laythe. When I'm there, I'll drop off the RCS tug in orbit and descend to the surface, then SSTO off the surface and dock with the RCS tug as a proof of concept.
Then I'll send out the other components of my Laythe station and base. It's going to take a lot of launches but I hope to be able to do a lot of the work today. I'll post pics later.
Oh and I know what you mean about accidentally launching ships with crew on board. It's extremely frustrating that they reset your crew preference every time you edit the ship in the VAB. I forget about it myself and often have to restart missions because of it. In fact, that's how I wound up with extra Kerbals on my LKO fuel depot that I had to go and rescue.
I really can't wait for the new subassembly feature in .22. If you hadn't heard, we'll now be able to save parts of rockets and load them into the VAB while building stuff. So I can build a launcher, save it, and then load it to use with different cargos and landers, etc. That's going to save me sooooo much time from having to rebuild the same vehicle.
warpus
Sommerswerd asked me to change this
Yeah, the subassembly stuff I'm really excited about! Mind you my launchers tend to be sort of specialized depending on what I'm putting into orbit, but the difference is really mainly the number of solid fuel boosters.
I've got 2 tankers on the way to Laythe and a third one about to burn for an intercept. My guys are coming home soon.
Antilogic, I just noticed we both posted rescue missions at almost the same time heh. I've never been to Moho either, I might just have to check it out when 0.22 comes out.
I've got 2 tankers on the way to Laythe and a third one about to burn for an intercept. My guys are coming home soon.
Antilogic, I just noticed we both posted rescue missions at almost the same time heh. I've never been to Moho either, I might just have to check it out when 0.22 comes out.
warpus
Sommerswerd asked me to change this
Ok so turns out "soon" in kerbal terms is 6 hours later
I ended up using one of my tankers to push my guys all the way to Kerbin. I had to refuel that tanker using the other tanker first.. and had a hell of a time trying to get an intercept to get back home. Once in orbit around Kerbin I built a retrieval capsule, sent it up in a simple rocket, docked with it, and got my guys on the ground. Their 6 and a half year long mission is finally over! They visited Vall, Bop, and Laythe.
I'm done with KSP for a while
I ended up using one of my tankers to push my guys all the way to Kerbin. I had to refuel that tanker using the other tanker first.. and had a hell of a time trying to get an intercept to get back home. Once in orbit around Kerbin I built a retrieval capsule, sent it up in a simple rocket, docked with it, and got my guys on the ground. Their 6 and a half year long mission is finally over! They visited Vall, Bop, and Laythe.
I'm done with KSP for a while
hobbsyoyo
Deity
- Joined
- Jul 13, 2012
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Congrats dude!
None of my plans worked out. I had the tanker in orbit but I couldn't dock with it. The tanker was still attached to it's booster core and it was a real beast to maneuver. Just a nightmare. I spent a couple of hours chasing the LVL-1c around trying to dock. Finally I undocked the RCS tug from the LVL-1c and scooted it over to the tanker. It turns out lining up the clampotron sr. is much more difficult than the smaller clampotrons. I have no idea, but they are kind of buggy and the magnets don't tug them together until you're .00001m apart. It kind of sucks.
Anywho, I docked the RCS tug to the tanker and tried to use the extra RCS thrusters to maneuver it better. Only problem was that because the tug's thrusters weren't lined up with the CoM, the whole thing tumbled when I tried to maneuver it. I switched over to the lander to try and use it to come in and dock and that didn't work out well. The last thing I tried was to ditch the core stage on the tanker to lighten the load but even that didn't freaking work.
So I finally broke down and broke out the calculator. I designed a lander with enough deltaV to get to orbit around Laythe and that had a T/W > 1. It turns out the thing can nearly SSTO off of Kerbin which tells me if I had just stopped being a turd and used some math to begin with, my first lander would have worked because it's only trivial to make a Laythe-SSTO lander capable of doing Kerbin-SSTO. But since I calculated the deltaV requirement for Laythe orbit, I don't even have to test it by SSTOing off of Kerbin, it has plenty of deltaV to spare at Laythe.
Right now designing a booster that will be able to take it all the way to Laythe. Initial tests are good, hopefully I'll be able to finish it tomorrow...I'm going to see Gravity now.
Congrats again!
None of my plans worked out. I had the tanker in orbit but I couldn't dock with it. The tanker was still attached to it's booster core and it was a real beast to maneuver. Just a nightmare. I spent a couple of hours chasing the LVL-1c around trying to dock. Finally I undocked the RCS tug from the LVL-1c and scooted it over to the tanker. It turns out lining up the clampotron sr. is much more difficult than the smaller clampotrons. I have no idea, but they are kind of buggy and the magnets don't tug them together until you're .00001m apart. It kind of sucks.
Anywho, I docked the RCS tug to the tanker and tried to use the extra RCS thrusters to maneuver it better. Only problem was that because the tug's thrusters weren't lined up with the CoM, the whole thing tumbled when I tried to maneuver it. I switched over to the lander to try and use it to come in and dock and that didn't work out well. The last thing I tried was to ditch the core stage on the tanker to lighten the load but even that didn't freaking work.
So I finally broke down and broke out the calculator. I designed a lander with enough deltaV to get to orbit around Laythe and that had a T/W > 1. It turns out the thing can nearly SSTO off of Kerbin which tells me if I had just stopped being a turd and used some math to begin with, my first lander would have worked because it's only trivial to make a Laythe-SSTO lander capable of doing Kerbin-SSTO. But since I calculated the deltaV requirement for Laythe orbit, I don't even have to test it by SSTOing off of Kerbin, it has plenty of deltaV to spare at Laythe.
Right now designing a booster that will be able to take it all the way to Laythe. Initial tests are good, hopefully I'll be able to finish it tomorrow...I'm going to see Gravity now.
Congrats again!
Spoiler :
Yeah, I couldn't exploit the Oberth effect because I had to dock my three modules together around Kerbin and then I had to rescue the guy at Moho, requiring a matching orbit. It appears that I took the most efficient route on the Kerbin to Moho transfer, and I approximated it as best as possible on the return. My final trick to make this work (because if you build my ship, you will run out of fuel if you don't do this exactly right) was to leave Moho when Moho was at the ascending/descending node with Kerbin, and my ship was in an equatorial position and could burn out of Moho's gravity well at the proper heading. That way, I only had to burn a tiny amount of fuel to correct the momentum that would take me over Moho's poles instead of being several hundred thousand kilometers out of position the moment I left Moho's well (requiring massive inclination correction burns).
I'm particularly partial to the picture of my two ships about 10 meters apart (and indeed, I made sure to get them close enough to snap it instead of letting the kerbal space-walk 100m over). Reminds me of those shots in The Next Generation where they had the Enterprise D and an old Excelsior flying side-by-side to transfer an admiral or something.
Beat you by seconds!
I've been lurking and watching your dueling Laythe missions with interest. I've put conventionally-powered probes in orbit Jool and Eeloo, but that's about it for the missions past Duna. I'm taking notes for a manned mission.
I would hardly call it a race, he whooped me thoroughly.
I had to otherwise I would have even more kerbals stranded near Moho. The Voyager is designed for comfort and coolness, not efficiency like the Crotch Rocket.
The single stage to orbit craft is a bit of an achievement, though, I've just been focusing more on cool-looking transport ships. I desperately need to figure out how to store more fuel on the craft with removable tanks, though, because unlike with the outboard engine design, I cannot simply tack on more big tanks tanks and jettison them one-by-one.
hobbsyoyo
Deity
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- Jul 13, 2012
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- 26,575
I spent all freaking day trying to get my lander out to Laythe. Once again, I suspect I massively overbuilt the launcher. :/
Anywho, I finally did get an encounter and I spent the last hour trying to figure out how deep into the atmosphere do I need to go to aerocapture. If I come in at 16km periapsis, then I burn up. If I come it at 21km, I have to burn up too much fuel to get an orbit. Trying to hit that sweet spot between those two is a major challenge. I'm currently cruising about 21days out from the encounter, so just a tap from my RCS system is enough to send my periapsis up or down by tens of kilometers. I know I can do this, but I'm just burnt out for today, pun not intended.
I have no idea how you guys have patience for these long missions...you all must be far better pilots than I am because half of the time I play I am simply reloading to the last point before I screwed up something and trying again...and again and again and again.
It took me half the day just to get to Jool in a position where a Laythe encounter was even feasible. The launcher spins like crazy after I drop the first two stages and it doesn't stop until I'm down to the core stage and the RCS has enough power to overcome the spin. I think with the boosters still on that the stack is simply too massive to slow down. The core stage itself is massive - 3 orange tanks w/ 8 nervas and 1 mainsail. I'm able to get to the Joolian system pretty easily but because the core/lander is so big my burn times are long and I know I'm actually wasting a lot of fuel. If I cut down the core stage I could burn for far shorter times and thus actually save fuel by not bringing as much fuel. The trick is to get it just right, not too much, not too little.
Although it is comforting to have a third of your fuel left in your core stage when you zip by Laythe without ever even touching a drop of the lander's fuel.
From here on out I'm going to use my formulas to design my craft; I've had enough of this guess, build, fail, guess again crap. I'd be happy to share the formulas I use with you all if anyone is interested.
Here's a couple of things that I really hope they fix:
SAS needs to keep your heading damnit! It's so frustrating to set your heading and activate SAS only to see your craft (which is balanced) wander off course. Particularly during ascent, when you try and burn towards the horizon at 90deg, the SAS will keep you on 90deg but you will drift off of the horizon every.single.time.
Struts should be increased in strength by a factor of 2 or 3.
We need more precision with the maneuver node handles. I'm sick of not being able to get what I want from a maneuver node because I moved my mouse .00001cm too far to the left.
Better camera angles in map view. This becomes a huge issue at Jool because of the scale of the system and how busy it is. When you are coming into the Joolian system but you're still billions of km's out, all of the moons are all squished together in the map view which makes it insanely difficult to see what's going on and what is where when you are trying to plan a burn.
The VAB should show you how much your craft weighs and what your T/W ratio is. I hate having to either add everything up or load it onto the launch pad just to know the vehicles weight.
The maneuver node should show encounter angles on the map view so you know exactly when to launch instead of having to go to a web calculator to get the angle and then busting out a protractor and holding it up to the screen.
The game should have a database of how much deltaV it takes to get to various places so we don't have to go to the internet for that info.
Docking clamps need to be much stronger and the clampotron Sr's need to be easier to engage.
All of these issues would make the game soooooo much more playable. I find I waste a ton of time dealing with these things instead of actually playing the game.
I think this picture was taken on a failed attempt to get to Jool. I wind up with about 1/3 of my fuel left in the core by the time I get to the Jool system if I set up my burns correctly. I never stop off in LKO, I just burn my NERVAs and turn off my mainsails after my apoapsis marker clears the atmosphere (usually happens when I'm about 40km in altitude). Then I keep burning them for about 10 minutes or so and I get my Jool encounter. I *think* it's an extremely efficient way to do it as I'm taking full advantage of the Oberth effect.
One thing I could do to make the core more manageable is to place decouplers above every orange tank and move the NERVA's to the top. That way I can drop each tank in the stack (and the mainsail) as they are spent. I'm currently hauling around two empty tanks and a worthless mainsail. Hmm I wonder though if I have enough fuel that the mainsail would be worth using instead of the NERVAs. When you have to burn really long times at low thrust there are times when you are actually wasting fuel versus if you had a more powerful (but less efficient) engine that burns much shorter. The trick, as usually, is figuring out the exact balance between the two.
Anywho, I finally did get an encounter and I spent the last hour trying to figure out how deep into the atmosphere do I need to go to aerocapture. If I come in at 16km periapsis, then I burn up. If I come it at 21km, I have to burn up too much fuel to get an orbit. Trying to hit that sweet spot between those two is a major challenge. I'm currently cruising about 21days out from the encounter, so just a tap from my RCS system is enough to send my periapsis up or down by tens of kilometers. I know I can do this, but I'm just burnt out for today, pun not intended.
I have no idea how you guys have patience for these long missions...you all must be far better pilots than I am because half of the time I play I am simply reloading to the last point before I screwed up something and trying again...and again and again and again.
It took me half the day just to get to Jool in a position where a Laythe encounter was even feasible. The launcher spins like crazy after I drop the first two stages and it doesn't stop until I'm down to the core stage and the RCS has enough power to overcome the spin. I think with the boosters still on that the stack is simply too massive to slow down. The core stage itself is massive - 3 orange tanks w/ 8 nervas and 1 mainsail. I'm able to get to the Joolian system pretty easily but because the core/lander is so big my burn times are long and I know I'm actually wasting a lot of fuel. If I cut down the core stage I could burn for far shorter times and thus actually save fuel by not bringing as much fuel. The trick is to get it just right, not too much, not too little.
Although it is comforting to have a third of your fuel left in your core stage when you zip by Laythe without ever even touching a drop of the lander's fuel.
From here on out I'm going to use my formulas to design my craft; I've had enough of this guess, build, fail, guess again crap.
I'd be happy to share the formulas I use with you all if anyone is interested.Here's a couple of things that I really hope they fix:
SAS needs to keep your heading damnit! It's so frustrating to set your heading and activate SAS only to see your craft (which is balanced) wander off course. Particularly during ascent, when you try and burn towards the horizon at 90deg, the SAS will keep you on 90deg but you will drift off of the horizon every.single.time.
Struts should be increased in strength by a factor of 2 or 3.
We need more precision with the maneuver node handles. I'm sick of not being able to get what I want from a maneuver node because I moved my mouse .00001cm too far to the left.
Better camera angles in map view. This becomes a huge issue at Jool because of the scale of the system and how busy it is. When you are coming into the Joolian system but you're still billions of km's out, all of the moons are all squished together in the map view which makes it insanely difficult to see what's going on and what is where when you are trying to plan a burn.
The VAB should show you how much your craft weighs and what your T/W ratio is. I hate having to either add everything up or load it onto the launch pad just to know the vehicles weight.
The maneuver node should show encounter angles on the map view so you know exactly when to launch instead of having to go to a web calculator to get the angle and then busting out a protractor and holding it up to the screen.
The game should have a database of how much deltaV it takes to get to various places so we don't have to go to the internet for that info.
Docking clamps need to be much stronger and the clampotron Sr's need to be easier to engage.
All of these issues would make the game soooooo much more playable. I find I waste a ton of time dealing with these things instead of actually playing the game.
I think this picture was taken on a failed attempt to get to Jool. I wind up with about 1/3 of my fuel left in the core by the time I get to the Jool system if I set up my burns correctly. I never stop off in LKO, I just burn my NERVAs and turn off my mainsails after my apoapsis marker clears the atmosphere (usually happens when I'm about 40km in altitude). Then I keep burning them for about 10 minutes or so and I get my Jool encounter. I *think* it's an extremely efficient way to do it as I'm taking full advantage of the Oberth effect.
Spoiler :
One thing I could do to make the core more manageable is to place decouplers above every orange tank and move the NERVA's to the top. That way I can drop each tank in the stack (and the mainsail) as they are spent. I'm currently hauling around two empty tanks and a worthless mainsail. Hmm I wonder though if I have enough fuel that the mainsail would be worth using instead of the NERVAs. When you have to burn really long times at low thrust there are times when you are actually wasting fuel versus if you had a more powerful (but less efficient) engine that burns much shorter. The trick, as usually, is figuring out the exact balance between the two.
