Magicide

I just came across this on Reddit and didn't see it posted here yet: http://www.planetary.org/blogs/casey-dreier/2013/20131115-nasa-just-cancelled-its-asrg-program.html I didn't realize the RTG was such an inefficient power source or that the deep space missions required that much Pu 238. It seems foolish to cancel a nearly complete program that promised a 400% efficiency increase. It appears they not only killed the more efficient RTG but also cut the Plutonium 238 production that all deep space missions require. In this PDF http://science.nasa.gov/media/medialibrary/2013/07/15/Green_PPSubcommittee.pdf it talks about scaling production from 1.0-1.5 to 1.5-2.0 kg/year of Pu 238. The first article states that a deep space probe requires 10 kg or more which means at current production rates that is only one mission beyond Saturn every 7-8 years. With this new decision, further Pu 238 production has now been halted as the administration feels there is sufficient supply on hand for expected future needs. I'm guessing future needs implies outer planet exploration is not in the cards for any time soon. Hopefully we can rely on the Russians, Chinese and Indians to go push the boundaries...

Actually that is quite helpful, I read before that for max efficiency in the low atmosphere you don't want to be moving more than 250 m/s below 10 km. By that chart though, once you are above about 15 km the atmosphere starts to become negligible. Why would you not want to have a 3 or 4 TWR at that point so that your burn to apoapsis is as short as possible? It seems like the extra engine weight needed for that acceleration is justified by spending significantly less time requiring vertical thrust to counter gravity. Also with a high TWR you can thrust prograde closer to the apoapsis to circularize your orbit which is more efficient that having to burn for a longer time before/after hitting apoapsis.

Does engine efficiency in KSP scale 1:1 with throttle? I've read that most rockets work at maximum efficiency at full throttle and that they can only be throttled down to about 50% before there are issues with the propellant burning/pumping correctly. Also why would you not want to reach orbit as quickly as possible? Every second you spend thrusting to orbit is another 9.81 m/s^2 of of downwards acceleration you are having to counter with more fuel. Isn't it then most efficient to thrust at the maximum rate your craft can sustain?

As they are it would be quite a long time to meet and as others have said, they would pass quickly. If you wanted to set up an intercept you would do best by taking Jester 4 to a higher circular orbit and then plotting an intercept at Jester 3's periapsis or apoapsis once they would both meet there, you can then burn prograde/retrograde to adjust the other orbit node to match while at closest approach. It is definitely easier matching circular orbits but with a bit of maneuver node playing you can match eccentric orbits easily enough.

The TWR at launch is 2.95 with a mass of 1184.5 tons and 34300 kN of thrust according to MechJeb, if it doesn't explode it easily carries the payload to high Kerbal orbit. The lander itself is 106.5 tons and carries enough fuel to make it to Kerbal orbit which should be enough to make it to the return ship from Laythe.

I'm sure someone can give a more precise answer but the short of it is you either fast forward to the next window or use extra ÃŽâ€V. Depending on how far out of the ideal launch window, it can require significantly more fuel to get there.

http://imgur.com/a/DqZqK#0 I am trying to launch my heavy lander to send Jeb to Laythe and back. However I am having a frustrating time getting my launch vehicle to actually launch. The pictures show the story just as well but here is my issue: I like launching stupidly large ships and was running into physics issues trying to use a 4 layer asparagus launcher made of stock tanks. So I downloaded KW Rocketry to use the larger tanks/heavier engines. Except no matter how much I reinforce my ship, it usually falls apart on the launch pad once the physics initialize. I've found the work around to that by launching the second the physics come online and throttling up before the rocket falls to the ground. Except once the rocket gets to 3000-4000 feet (different depending on the rocket design I use) I get hit with a sudden heavy jolt out of nowhere. If I throttle down through that altitude, the ship is still hit with a jolt but it usually survives and I can go back to full throttle. Most of the time I can then happily carry on to orbit. Except... about 1 in 5 launches, when a stage runs out it causes one of the now empty tanks to jolt up and down like it's attached with bungee cords. If it bounces the wrong way it knocks something important loose and the kraken feasts. I can solve this by killing thrust and dumping tanks a second or two before the fuel runs out. But between throttling down at 3000-4000 feet and killing thrust every asparagus stage drop I'm wasting a lot of delta V. I know I'm pushing against the limits of what the engine wants to work with but is there anything I can do to prevent this?

Actually I just tried running struts from each of the outer tanks to the central core and then between each of the outer tanks. It appears to fix the issue but my poor ship goes from advanced rocketry to looking like the wright flyer.

I attached the girders directly to the tank and then the outer tanks directly to the other end of the girders. As an experiment I just tried a stripped down craft consisting of only a fuel tank, probe core, girder and small tank/engine attached to the girder. Anything from 2x to 8x symmetry leads to the ship rotating at an increasing rate. I experimented with the other girders, decouplers and pylons as well. They all exhibit rotation right from launch if any sized tank + engine is attached to them. I also tried several different engines and they all rotate. I tried stiffening the assembly with struts but it doesn't appear to make any difference. What does work is disabling the engine gimbal so it's the most likely culprit. This wasn't an issue prior to .22 so I'm thinking something got buggered up in the last patch. This definitely throws a wrench in my plans as the interplanetary vessel I've been assembling in orbit relies on nuclear engines attached to girders... now it looks like I get to deorbit it and start from scratch.

Hello! I have been having fun with KSP for a few months now and have sent many kerbalnauts to their doom in the name of pushing boundaries. However since .22 I've noticed a problem and I don't know if it's the game or me. I have had several ships lately that should have flown straight and true instead spin wildly. Attached is a photo of my prototype concept for a super heavy lander. It is built in 6x symmetry and the center of mass and lift are both dead center on the middle of the vessel. If I reattach the girders in 4x symmetry it will sometimes launch straight but other times it will spin as well. The only time I have a 100% success rate regarding spinning is if there is only one central engine. I have noticed that my heavy launcher which is a central orange container and three additional layers of orange containers in 6x symmetry also spins every single launch while the same design used to be perfectly stable. I have my suspicions that something more is going on but maybe it's a simple fix. I am not running any mods. Hopefully someone can help me out. Thanks! http://imgur.com/S9q0V01