uncle_jew

Wouldn't you lose even more delta v this way? Because when landing on the equator, I would have to do a retro burn. But when changing the direction by 90 degrees at the equator without stopping, I would do a burn at like 45 degree angle, killing the latitudal velocity and building up the velocity along the new orbit at the same time.

Hello, assuming my spacecraft is sitting on a (North) pole, and I need to launch it into an equatorial orbit. How to do it with the least delta-v needed? I can obviously simply launch it on a suborbital trajectory towards the equator, then do a big burn to change the direction by 90 degrees and to reach the orbital speed, but this requires almost twice the delta-v needed to launch from the equator. Are there any significantly cheaper ways of achieving the same goal?

How do you close the "Review stored data" window without having to click on "Keep experiment" for every experiment stored? Gets tiresome when you have 20+ experiments. I don't see a "close" button. I discovered that switching to another spacecraft and back closes the darn window - but is there a simpler way? Thanks

Hello, is there any software/website for planning real Solar System travel, just like we plan orbits and maneuvers in KSP? So that you could see e.g. how much delta-v is needed and how long it would take to reach Neptune and enter an orbit around Triton?

Hello, I want to launch a mission into a low Kerbol orbit (5000km periapsis). Tried it twice, both times my spacecraft exploded due to overheating. On the 2nd attempt, I also had a medium-sized radiator attached, which didn't seem to help much. How do you keep the spacecraft cool? Is it possible to calculate the needed number of radiators? Unlike solar panels, radiators are shown without any numbers that would indicate their heat dissipation. Do radiators cool the whole spacecraft, or only the part they are directly attached to? I have KSP v1.0.4 Is it alternatively possible to construct an "umbrella" made of structure panels to shield the spacecraft from the solar heat? Does the KSP physics engine support it? Thanks!

If drills break your ships, make sure the non-rotating part of the drill doesn't touch the surface when the drill is extended. This was my first mistake when I started drilling - I mounted drills too low. When extended, their non-rotating parts put pressure against the surface, adding stress to my ship and often causing it to break up. Only the extensible rotating portion of the drill should go below the surface. Mining makes it much easier (and cheaper) to explore the Kerbol system, but it kills a lot of the fun. Because there is no longer any pressure to design efficient spaceships - just launch something with almost empty tanks into LKO using cheap SRBs, fill up tanks at my LKO fuel depot and then fly for free. I don't use docking for mining operations, because I don't see any point doing it - fuel is free, so hauling the ISRU converter to the surface and back to orbit costs nothing (plus I don't need big ore tanks this way). I developed two types of mining operations. 1) A big flying fuel factory for mining Minmus and delivering the fuel to LKO, with nuclear engines. Nuclear engines are needed here, because with conventional engines, I would burn more than the half of my fuel for the transfer to LKO and for the later return back to Minmus. 2) A medium-sized craft for exploring the Kerbol system, equipped with drills, an ISRU converter and fuel cells for powering all this. It has slightly over 5000m/s deltaV when fully fueled, thus allowing unlimited free travel, except to the surface of Kerbin, Eve and Tylo (where my TWR isn't sufficient). But as I said, these basically put you into the "superuser mode" - you suddenly can do anything you want, which kills the fun.

Is there any good trick for determining when it's best to eject from a low orbit for a transfer to another planet/satellite? The problem is, you can only plan a maneuver up to one orbit ahead. And since the orbital period of low orbits around bodies is short compared to orbital periods around the Sun, I don't see a way of checking e.g. when it is better to eject from Moho to Eve: in 60 or in 90 days? For launches from LKO, I simply have a spacecraft in exactly the same orbit as Kerbin, but a few days ahead of Kerbin. I plan the interplanetary transfer using this spacecraft first, which allows me to select any time during a whole Kerbin year, so that I can fine tune the desired launch and LKO ejection time. Finally, I use the time of this maneuver for the LKO ejection burn. But for launches from other bodies, this would require putting a separate spacecraft into the Sol orbit ahead of each body. Is there a more generic method of planning ejections into interplanetary orbits?

Hello, assume I have a fully fueled probe in the low Kerbin orbit that I am planning to fly to Moho. I have two ways of ejecting from LKO towards Moho: 1) Direct ejection burn from LKO 2) Go to my refueling base in a high Kerbin orbit (between Mun and Minmus), refuel there, then eject from that orbit to Moho. What is a better option if I want to arrive at Moho with as much delta-v remaining as possible? I understand an ejection burn from LKO has the advantage of the gravity well, which is lacking if I eject from a high orbit. So is the advantage from the gravity well effect bigger or smaller than the advantage of leaving fully fueled from a high Kerbin orbit, thus needing less energy to escape Kerbin?

Spent half an hour looking for a spacecraft I left in the Jool orbit two Kerbin years ago. Turned out its orbit got perturbed by Tylo and Laythe and it crashed directly into Jool while I was attending to business in the inner Kerbol system. Indeed, I remember hearing some explosions, but I thought it was a spent second stage or the like... Time to hire a new engineer in place of the deceased one, send him to Mun and Minums to gain XP, then replenish my space fleet in the Jool system.

I stopped out of boredom. After getting all possible tech advances, there were no more any rewards left, and contracts started kind of repeating themselves too. The remaining fun was killed by a multipurpose spaceship I built, which contains an onboard ISRU and a mining excavator, has 5000 m/s of delta-v and costs $165K to build and launch. With such ships, I have free unlimited travel across the whole Kerbol system, and the only tasks requiring custom built spacecraft are landings and takeoffs on Eve and Tylo. So the stuff simply stopped being challenging for me and with all bodies visited, became boring routine work.

Will try that, thanks! After more trying, I also did manage to use the Jool gravity well to my advantage - my mistake was choosing the apoapsis of the initial elliptical orbit around Jool to match the Pol orbit - this way, raising the periapsis became too expensive. If instead I enter the elliptical orbit with the highest possible apoapsis after passing by Jool, then raise the periapsis to match the orbit of Pol, then lower the apoapsis, I am able to shave off around 460 m/s from 1329 m/s required for a direct Pol orbit insertion.

Hello, I am trying to arrive at Jool by a Hohmann transfer from Kerbin so that my spacecraft would end up in the same orbit as Pol. If I adjust my arrival trajectory so that it "touches" the Pol orbit, I can get into the Pol orbit by doing a retrograde burn at the periapsis with a delta-v of 1329 m/s. Is it possible to use the gravity well effect to insert into the Pol orbit with a smaller delta-v? Burns done inside a gravity well are supposed to be more efficient due to the exhaust being left with less total energy, right? I tried nudging the arrival trajectory so that it passes by Jool inside the Laythe orbit. If I do this, I can get into an elliptical orbit touching the orbit of Pol from the inside by doing a retrograde burn at the periapsis with 537 m/s. However, to circularize the resulting elliptical orbit, I need another burn with 865 m/s at the apoapsis. So the total delta-v in this case is 1402 m/s, which is even higher than 1329 m/s needed for a direct insertion into the Pol orbit. Is there anything I am missing here, or is a gravity well generally unusable to get into circular orbits? Thanks

Hello, I have a contract to rescue a kerbonaut from an elliptical Kerbol orbit (periapsis near the Kerbin oribit, apoapsis behind the Dres orbit). Only after accepting it, did I learn that the he was in a [B]retrograde[/B] orbit around Kerbol. Are there any "smart" options to rescue him without needing crazy amounts of delta-v? Rescuing him near the periapsis would need 14-16km/s of delta-v just to reverse the orbit direction, pick him up and reverse the orbit direction again. I understand I can pull this off by strapping an external command seat to an ion drive, but are there any tricks with orbital mechanics that would let me accomplish the mission with chemical rockets? I hate the ion drive, because it is so slow, even with the 4x physics warp I would have to wait for almost an hour to get the desired delta v.

Thanks for the suggestions!

Here is a pic of my plane: http://i.imgur.com/eCX7VFM.png The round barrel after the cockpit is structural fuselage, not a fuel tank - I am simply loading slightly less oxidizer than fuel to compensate for extra fuel consumed by ramjets.

Hello, I built a simple SSTO spaceplane with two ramjets and a single LV-T45 engine. Getting to orbit is surprisingly easy, but how do you land the thing? I lower the periapsis to 25km and set the pitch to about 30 degrees to induce some aerobraking before entering dense parts of the atmosphere. But after slowing down, the plane becomes nearly uncontrollable and enters a flat spin. I could regain control by pumping the remaining fuel to the forward tank (in order to bring forward the CoG) and firing the engine, but still the controls are very shaky (compared to the fully fueled plane during launch, which was a joy to fly). I understand you can cheat by mounting huge reaction wheels (since unlike the real world, they don't need to be desaturated in KSP), but I would prefer a physically plausible spaceplane. Is there a way to bring a spaceplane all the way down in a controllable fashion, without it spinning out of control during some of the descent? And is there a way to make the spaceplane empty both fuel tanks at the same rate, instead of draining the front tank first, shifting the CoG to the back?

8-9km (even 100km) is not a problem in a solar orbit. The reason why you need close approaches in low orbits is that due to the curvature of the orbit, spaceships in different orbits start drifting relative to each other, which makes an approach from a long distance very difficult. But the curvature of a solar orbit is very low, so if you arrive at a point e.g. 100km from the target spacecraft and cancel the relative motion, you can just give your spacecraft a delta v of like 5m/s directly towards the target, and arrive almost exactly at a target a few hours later.

Hello, I am using the KER plugin to get delta v etc. Sometimes, when I perform undocking, KER becomes unavailable for the undocked part. The KER button becomes black and unresponsive, the KER window disappears. If I switch to the other spacecraft, KER becomes available again. And disappears again if I switch back to the spacecraft that has the problem. Is this a known problem, and is there any way to solve it apart from saving and restoring the game?

Hello, is there any way to tell the specialization of kerbonauts without going into the astronaut complex? E.g. I have 4 kerbonauts onboard and need to repack the parachute. So I need to get an engineer on the EVA. But how do I tell, which one of the kerbonauts is an engineer? Is there a way? Thanks

You can add some beams protruding outside to the middle of the stack. Then add struts between the ends of these beams and rocket elements above/below them. So you would get some latticework surrounding your rocket.If beams are aesthetically unappealing - place them on decouplers and throw them away once in orbit.

You can also build a simple turbine using a rocket engine and something round with winglets serving as turbine blades.Or, just mount rocket engines on the rotating part in the tangential direction. This results in very spectacular failures :DI think there might even be a practical aspect in it, because I think it should be possible to make a forklift using a rocket engine, and adjust the height by varying the thrust.

Wow, I didn't realize you could shave off the ablator in the VAB... Hmmm. After a Hohmann transfer orbit, I arrived at Duna with ~1300m/s delta-V. I then aimed my ship to pass 8km above its surface - this produced enough aerobraking to land without doing any burns (except immediately prior to touchdown, since I didn't attach enough parachutes). Aerobraking got my speed down to ~450m/s, after which I deployed the parachutes. If there is enough air resistance to land, there must be enough air resistance to aerobrake too... or am I getting this wrong? Or is the margin for error simply too thin?

Hello, I am trying to deliver a refueling space station to an orbit around Duna with several landers/tugs/probes attached to its sides with TT-38K radial decouplers. But I ran into a problem: after I detach these landers, their target indicators don't work correctly, which makes dockings very difficult. It seems that after you detach a vessel mounted on the side of the rocket, its target indicator still assumes the original rocket to be the "center" of the vessel, which causes the target indicator to produce an offset. I built a simplified vessel that demonstrates the problem. Here is a commented screenshot that shows the problem Here is the launch configuration Here is the craft file Is it a known problem/bug, and is there a workaround? Stacking multiple landers atop each other results in a very wobbly rocket difficult to control, so I would prefer to mount them on the sides instead.

Don't aim for the Kerbin surface - your trajectory should only "touch" the Kerbin atmosphere. The indicated apoapsis at Kerbin should be between 24-30km. Also, make sure the cross section of the lander is big enough (e.g. if you try landing a long thin object pointing retrograde - it will not decelerate fast enough). For the first landing attempt, maybe just try landing the capsule with an attached heatshield and a parachute (detach everything else with a decoupler prior to entering the atmosphere).

Hello, don't want to open several threads for trivial questions. So here are all questions at once: 1) Engine performance on Duna - does "ASL" or "Vacuum" Isp apply? I want to build a small reusable Duna lander. I understand the Duna atmosphere is much thinner than on Kerbin - so if I use e.g. the LV-909 "Terrier" engine, will it produce the "vacuum" Isp of 340s, or the much worse "ASL" Isp of 85s? 2) Purpose of rovers Apart from the fun of driving around, do rovers (as opposed to static landers) have any advantages? They don't drive very fast, so except at KSC, you will not want to drive them to other biomes. 3) Droppable heat shield - do you need a decoupler? I always use a decoupler to drop the heat shield prior to landing. But once, I right clicked somewhere on the lander and got an option to "drop heat shield" (or something like that). Couldn't reproduce this since - so can you discard a heat shield without using a decoupler, and if yes, where (and when) are you supposed to click? 4) When is a heat shield needed? Is there any way to determine when a heat shield is required and when not? E.g. when entering a Duna atmosphere with 1300m/s with a lander consisting mostly of a Rockomax X200-16 fuel tank, do I need a heat shield or will the fuel tank absorb the delta-V without too much heating? 5) Aerobraking - how to aim? How do I determine the proper periapsis for aerobraking (without landing)? E.g. I am approaching Duna with 1400m/s - what is the proper aerobraking altitude to go into orbit? Thanks