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On February 24 2014 18:19 Amui wrote:Nuke engines are pretty terrible for just getting to the mun or minmus. They don't provide enough efficiency to justify the massive weight. For my lander craft above, a nuke would be a full third of the weight. The increased ISP wouldn't make up for the ability to drop off excess tanks and store much more fuel for the same weight.. If you want to send like 20 tons to Jool, or send 100t into orbit around the mun, then you can justify using the nukes. Show nested quote +On February 24 2014 18:10 Daumen wrote:
So the small LV-909 is actually better to use while in Space. High Vac Isp, its more efficient in Space and its also less heavy, making the craft slightly easier to get off Kerbin :O
Am I right ? Thats the kind of Tip Ive been looking for. Very helpful ;D Just be careful because that engine doesn't generate electricity. Also note that for very small craft(sub 5T) the tiny rockomax's can be even better than the LV909 because of the tiny weight.
That's true. It all comes down to the rocket equation, so you can find out what is best for what via math. Or you can just try attaching different engines with Kerbal Engineer/MechJeb to see what gives the best result.
As a rule of thumb though, nukes are #1 for interplanetary travel.
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Magic Woods9326 Posts
I meant to write without ;;
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Dont rly want to use mods ;D
Another question: is it normal that markers like Periapsis and Apoapsis are twitchy? that makes it rly hard to navigate sometimes.
God damn, RCS is so whoppy when you dont know where to put it >.< I should just try to put it around/into the Center of mass, right?
Ok guys, this is it, I need your help guys ;D. I've got a Mission for you... sort of... :O
My trusty Jebediah is in a Circular Orbit around the Mun(see pic above). His SpaceCraft is a 3 Parter, a Sattelite, a rover and a Landing Unit.
I want him to:
1. Put the Lander with the Rover on the Mun somewhere, get Science (Observing unit & mystery goo etc).
2. Return the Lander + Rover to Kerbin!
3. Leave the Sattelite in Orbit around Mun
The Problem is Jebediah has no fuel!
I can barely manage to refuel my Fueling station, I just couldnt get to my Station with Fuel until I made this Monster:
+ Show Spoiler +
And this doesnt even has enough Fuel left to Fill my Station, and it "only" holds 1800 LiquidFuel. Maybe this is normal, but it feels like my Constructions are WAAAAYYY too inefficient and im doing something wrong :o
My Refueling Station is Orbiting Kerbin at ~80.000.
This is my tech tree + Show Spoiler +http://i.imgur.com/6FEDXo4.png
I would try to get another Massive monster to my Refuel Station, fuel up and then go to the mun, but I feel like thats so much work, there has to be a better way to construct Rockets, right? :< what would you build? If any1 wants to live up to the challenge, please build an example rocket and screenshot it ;D
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The markers get twitchy when you get close to a circular orbit. That's perfectly normal; when it comes to the vast distances in space, even double floating point math starts to show imprecision when its predicting things 1000km away. The imprecision is always there, but on an elliptical orbit, moving the nodes up or down 5m doesn't move the nodes very far along the orbit, meaning it doesn't twitch around. But If you're in a nearly-circular orbit, the imprecision could move the node tens of kilometers, which WILL show up on the map as twitching.
RCS should be placed around the center of mass, yes.
As for your fuel problem, you should consider asparagus style staging. Use symmetry to place 6 liquid boosters around the outside, have fuel lines connect them to the central stack so the central engine takes fuel from the boosters.
On launch, accelerate slowly. You want to hit 200m/s right around 10km altitude. This works out be a TWR (thrust to weight ratio) of about 1.2 or so. Preferably, build your rocket so that is its maximum TWR, or you're wasting mass on overly beefy engines. You can tell you're at the right TWR when your G meter sits just over 1G. At 10km, slowly start heading East (that's toward the ocean). You can also throttle back up to full once you're past 10km altitude. The reason you want to accelerate slower in the lower atmosphere is that you take unnecessary drag from air resistance if you go too fast. After 10km the air is thin enough for it to not matter.
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If you have trouble RCS balance, you may have expended a lot of fuel and shifted your center of mass. With the new and improved SAS it shouldn't be much of a problem, but I suppose if there was a massive shift it could be problematic. Since you are just trying to send a refueling craft for 1-time use it really shouldn't be a concern, anyway.
I have copied your tech tree and built this:
+ Show Spoiler [pics] +
.craft file http://s000.tinyupload.com/index.php?file_id=80161846563929913675
Launch profile is a bit tricky (circularization is done with super low TWR), since it is designed to leave behind no debris. That could be easily changed by adding another liquid booster. It even has ~70 m/s RCS delta v, so you can practice docking without worrying about running out of fuel.
An obvious improvement to the design would be proper asparagus staging in twos (built in 4s for time's sake) and adjusting TWR for each stage to increase efficiency.
I also finished constructing my Eve monstrosity. I have avoided doing Eve until now because the lag was horrific, but with the 0.23 improvements it seems tolerable.
+ Show Spoiler [pictures] +
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On February 26 2014 02:59 nimbim wrote:If you have trouble RCS balance, you may have expended a lot of fuel and shifted your center of mass. With the new and improved SAS it shouldn't be much of a problem, but I suppose if there was a massive shift it could be problematic. Since you are just trying to send a refueling craft for 1-time use it really shouldn't be a concern, anyway. I have copied your tech tree and built this: + Show Spoiler [pics] +.craft file http://s000.tinyupload.com/index.php?file_id=80161846563929913675Launch profile is a bit tricky (circularization is done with super low TWR), since it is designed to leave behind no debris. That could be easily changed by adding another liquid booster. It even has ~70 m/s RCS delta v, so you can practice docking without worrying about running out of fuel. An obvious improvement to the design would be proper asparagus staging in twos (built in 4s for time's sake) and adjusting TWR for each stage to increase efficiency. I also finished constructing my Eve monstrosity. I have avoided doing Eve until now because the lag was horrific, but with the 0.23 improvements it seems tolerable. + Show Spoiler [pictures] +
That can land AND take off from Eve? It looks a bit different from other craft I've seen built to perform that feat (although not as ridiculous as some I've seen built to land and take off from Jool) - good luck! (Someday, Eve, someday...)
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The lander has 10.5km/s delta v in atmosphere. I will dock using the return vehicle to position an engine part and lander, so they can easily dock without RCS (and engine part is uncontrollable). Then I can de-orbit without wasting fuel. I didn't go completely overboard with chutes, so I will have to try and stay as long as possible in the upper atmosphere and use engines to brake before chute opening and touchdown.
At the bottom of the mothership is a probe science lander, that saved some weight. The kerbal can collect the science and I have already placed a rover on Eve. If I should fail with my landing precision, I won't have to walk across the surface for an hour.
The return pod is on top of the science module atm and has no engine. At the end of the journey I will transfer the rest of the fuel in one of the engine parts and dock with it. Since command pods have RCS fuel now, it saved me at least 1 part^^.
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Thank you Nimbim ;D
I just had the best KSP experience of all time ;D
As you can see from my previous post, I had this little Problem with Jebediah Orbiting the Mun without fuel. Before you guys answered to my problem I just Launched my MONSTER Tank Truck to the Mun, Fueled up my Lander a bit and Landed on the Mun Successfully! yay.
I conducted some research on the Northeast Crater and have about 300 science docked up! I even drove around in my rover, wich I think looks pretty cool (my first manned rover that looked anything like an actual vehicle). But then I noticed: Neither my "Lander" nor my Rover had a Parachute to land on Kerbin... damn, I built that on my sattelite, I need to get back to my Sattelite...
I had very low fuel anyways... When I was returning to my Sattelite around the Mun I noticed that my Fuel is actually VERY short and that I had no Monopropellant left over for docking... fuck.
At least my sattelite had a bit of Monopropellant left. So I BARELY made it :D Now I have 9.55 LiquidFuel left. It was pretty close ;D
After much celebration I noticed... I have no Parachute on my Sattelite either... I dont have a parachute at all °_°... damn!
Now I will probably recreate nimbims design and get some fuel to the mun. Then Ill have to try and undock my science experiments, dock them to a craft that actually has a parachute and get it to Kerbin...
damn! If you fail to think about everything in this game, you have to be clever :D This is going to be the 3rd mission to save Jebediah...
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On February 26 2014 02:59 nimbim wrote:If you have trouble RCS balance, you may have expended a lot of fuel and shifted your center of mass. With the new and improved SAS it shouldn't be much of a problem, but I suppose if there was a massive shift it could be problematic. Since you are just trying to send a refueling craft for 1-time use it really shouldn't be a concern, anyway. I have copied your tech tree and built this: + Show Spoiler [pics] +.craft file http://s000.tinyupload.com/index.php?file_id=80161846563929913675Launch profile is a bit tricky (circularization is done with super low TWR), since it is designed to leave behind no debris. That could be easily changed by adding another liquid booster. It even has ~70 m/s RCS delta v, so you can practice docking without worrying about running out of fuel. An obvious improvement to the design would be proper asparagus staging in twos (built in 4s for time's sake) and adjusting TWR for each stage to increase efficiency. I also finished constructing my Eve monstrosity. I have avoided doing Eve until now because the lag was horrific, but with the 0.23 improvements it seems tolerable. + Show Spoiler [pictures] +
Are Nose Cones not a good idea? thought they had a positive effect in the frist stages.
edit: you forgot some rcs thrusters i think °_° im only able to navigate in 4 directions, makes it very hard to dock :D
I made it though, was a real hassle though.
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On February 26 2014 15:50 Daumen wrote:Show nested quote +On February 26 2014 02:59 nimbim wrote:If you have trouble RCS balance, you may have expended a lot of fuel and shifted your center of mass. With the new and improved SAS it shouldn't be much of a problem, but I suppose if there was a massive shift it could be problematic. Since you are just trying to send a refueling craft for 1-time use it really shouldn't be a concern, anyway. I have copied your tech tree and built this: + Show Spoiler [pics] +.craft file http://s000.tinyupload.com/index.php?file_id=80161846563929913675Launch profile is a bit tricky (circularization is done with super low TWR), since it is designed to leave behind no debris. That could be easily changed by adding another liquid booster. It even has ~70 m/s RCS delta v, so you can practice docking without worrying about running out of fuel. An obvious improvement to the design would be proper asparagus staging in twos (built in 4s for time's sake) and adjusting TWR for each stage to increase efficiency. I also finished constructing my Eve monstrosity. I have avoided doing Eve until now because the lag was horrific, but with the 0.23 improvements it seems tolerable. + Show Spoiler [pictures] + Are Nose Cones not a good idea? thought they had a positive effect in the frist stages.
In the real world they are. In this game, however, they actually increase drag and obviously have weight. So in KSP you're better off without, except aesthetically.
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On February 26 2014 15:50 Daumen wrote:Show nested quote +On February 26 2014 02:59 nimbim wrote:If you have trouble RCS balance, you may have expended a lot of fuel and shifted your center of mass. With the new and improved SAS it shouldn't be much of a problem, but I suppose if there was a massive shift it could be problematic. Since you are just trying to send a refueling craft for 1-time use it really shouldn't be a concern, anyway. I have copied your tech tree and built this: + Show Spoiler [pics] +.craft file http://s000.tinyupload.com/index.php?file_id=80161846563929913675Launch profile is a bit tricky (circularization is done with super low TWR), since it is designed to leave behind no debris. That could be easily changed by adding another liquid booster. It even has ~70 m/s RCS delta v, so you can practice docking without worrying about running out of fuel. An obvious improvement to the design would be proper asparagus staging in twos (built in 4s for time's sake) and adjusting TWR for each stage to increase efficiency. I also finished constructing my Eve monstrosity. I have avoided doing Eve until now because the lag was horrific, but with the 0.23 improvements it seems tolerable. + Show Spoiler [pictures] + Are Nose Cones not a good idea? thought they had a positive effect in the frist stages. edit: you forgot some rcs thrusters i think °_° im only able to navigate in 4 directions, makes it very hard to dock :D I made it though, was a real hassle though.
Yea, I just threw it together real quick for demonstration purposes. Maybe symmetry snapped back to 2 when I attached the RCS thrusters.
The aerodynamics currently used are very rudimentary. Nose cones and fairings only increase your weight+drag in the stock game. FAR (ferram aerospace research) makes it more realistic, but it's still far from perfect.
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What they said. I used to think nosecones helped - then I learned about the stock aerodynamics model. With Ferram Aerospace, they make sense (as do fairings) but in the stock aerodynamic model, things are simplified in such a way that the actual equations penalize you for the mass and drag of these items more than you gain versus just having a flat surface shoved into the atmosphere.
Of course, the aerodynamics model is not as simple as the hydrodynamics model, but I've seen people make boats for ocean going. (Hint - water is practically as nice to crafts as a roiling tub of brick to the face.)
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Canada8028 Posts
I believe nose cones slightly increase in-atmosphere stability at the moment. For all intents and purposes though, they're effectively decorations.
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So... my Jool mission. Pushing more because the new version (0.23.50) coming "soon" (premiering on KSPTV on Monday) and my ship is now 1033 parts and 702.65t
+ Show Spoiler +
I... have docked too closely. In order to detach the orange tail and put my last lander into place, I need to undock some things, add some adapters and length, and then re-dock.
I've already blown the thing up twice. Thank you quicksaves.
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Magic Woods9326 Posts
no cloud mod  ?
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No cloud mod. I have enough trouble remembering where the KSC is from orbit.
I have to figure out how to get the large Tylo lander from the front (on a small docking port) onto one of the seniors at the back. Not going to be easy.
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Magic Woods9326 Posts
On March 23 2014 01:56 felisconcolori wrote:
No cloud mod. I have enough trouble remembering where the KSC is from orbit.
I have to figure out how to get the large Tylo lander from the front (on a small docking port) onto one of the seniors at the back. Not going to be easy.
Just plant a flag :D
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Huzzah, my Jool ship is finished!
+ Show Spoiler +
The gallery is here
The docking was tough. But next... to Jool. Hopefully before Monday, when the Asteroid Redirect Mission marathon starts, and I think the updated itself will be not far behind.
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Magic Woods9326 Posts
0.23.5 is out :D! Gonna try it tomorrow ~~
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On April 02 2014 05:33 Epoxide wrote:
0.23.5 is out :D! Gonna try it tomorrow ~~
It is! The new tanks/engines are glorious. Tweakable light colors. The Claaaaaw. I now have to hope all of the mods are being updated feverishly. (Although the only one I use that seems utterly borked right now is MechJeb.)
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