Dave Kerbin

If you want to return I would really suggest Duna as your first destination. It combines low fuel requirements and a relatively simple mission sequence. A return from Eve is the biggest possible challenge in the stock game, though getting there is pretty easy. After you've managed Duna I would suggest Dres as your next target or an unmanned mission to Eeloo or one of Jool's moons (not Tylo though). For your ship more is always less, if you can remove any weight near the top it greatly reduces the weight you'll need at the bottom. To do that start thinking about missions backwards - build a small ship to complete the last part of the mission and then build the rest onto that. I have two careers, one of which did a fairly big and complicated Duna mission and another for the latest version of the game (0.23) that has a less complicated one. Pay particular attention to the little ship I came back in, that's the kind of thing you should be aiming for to keep your rocket from getting too big and unstable on the launchpad. I'm not sure how much help you want vs. how much you want to figure it out on your own - do you want any specific designs or modules you can use? If you want some specific designs then a screenshot of your current tech tree progress would be useful.

BobTwo - 23.3t - 331.8 science BobTwo is a close copy of BobOne, only this time the goal is to fly past Minmus. With solar power available some weight can be stripped off by removing most of the batteries. I could have used solar arrays and still been fine for weight but given how straight forward the flyby was (no landing or other situation where I might need power at a specific orientation and relatively short mission duration) I wanted to try an experiment. I equipped the ship with just 3 flat solar panels. Now normally it is important that probes have good solar coverage - if a probe enters a solar blind spot and time warps you'll have a dead probe that often can't be revived. Solar arrays are a good solution because they track the sun, so the only blind spots are if the ship itself blocks the array or array is extended straight toward the sun. 3 arrays typically provide complete coverage. My experiment was to place the 3 flat panels at the 3 compass points (with the ship's only battery at the 4th for balance), one on the back of the fuel tank and one on the side of each Science Jr. To provide coverage I tilted each panel 10 degrees in a different direction. So the panel on the back is tilted down, one of the side panels is tilted up and the other is tilted forward. In theory this should provide complete coverage so that the probe is kept charged no matter which way it is facing. Testing in Kerbin's orbit while I waited for the Minmus burn it was a success. The worst case scenario still generated 0.14em/s (8.4em/min) so the arrangement should work for probes right out to Eeloo. It only saves 0.0375t but on very small probes that can lose hundreds of delta-v. I spent the science on Electronics, giving me another light instrument, and on General Rocketry and Stability, giving me T45 engines and radial decouplers.

BobOne - 23.35t - 259.6 science My next mission will be to fly around the Mun and Bob seems like an approriate name as he was my most reliable, no-risk kerbal of the original three. BobOne carries 15 batteries for about 14 hours of operation once we reach orbit. The launch system is still relatively small, certainly smaller and simplier then what it takes to send a kerbal to Mun orbit. The first stage works out well, dropping just as I hit the gravity turn. I'm beginning to get enough data that I could start designing my staging to time with that turn (I've already been doing staging in my other career timed with the orbital coasting phase). BobOne blasts off to the Mun though it will be a basic pass by and not a complete orbit. I would have done a free return trajectory but I couldn't figure out if that was possible when combined with a low altitude pass (if I don't mind staying several hundred km above the Mun's surface it seemed relatively straight forward to setup a free return). Once in orbit around the Mun some readings can be taken (I also took 2 temperature readings on the way up from Kerbin) before exiting. BobOne exits the Mun's SOI 12 hours after the mission started. That puts it close to the 15 hour battery life. But not to worry because I already tested the solution in the last mission. After another 2 and half hours to get closer to the AP the probe makes a burn to bring it back to Kerbin. It will still take another 13 hours to land but with power almost out the parachute system is armed. From this point on no more power is needed, the ship will right itself with drag when it enters the atmosphere and the parachute system is entirely mechanical and will release when the probe descends below 6000m (real world automatic parachute systems where initially mechanical and the military still uses them since they don't rely on batteries or computers). I'll unlock solar panels and solar arrays with my science.

BillOne - 12.71t - 101.3 science I think a common misconception is that probes are one way (transmit only). Probes can be used to bring back data, it's just a matter of if the weight savings are useful. If you are carrying over a certain amount then it makes more sense to do a manned mission instead. This is very true with 0.23 since kerbals can remove data from experiments and store it inside the command pod. That had a big impact on how missions could be structured and what mass was required, since you could pack an unlimited amount of return science into a 0.6t Lander Can. But in some situations a return probe can make sense - it can do a similar mission for a fraction of the mass, so you don't need a big rocket to launch it or advanced engines like the Mainsails or LV-Ns. Especially for newer players getting things into orbit is usually half of the difficulty and making the payload lighter makes an impossible target become possible. BillOne is a sample return mission, but it's not a good example of a smart one. It's not by chance that this mission is named after my least favorite kerbal. The goal is simple - grab the material lab science close to Kerbin as quickly as possible so we can move on to other things. The rocket is good and simple, just two stages. We'll go up, grab the science and come back down. With batteries we don't have to worry about power for this short mission (there is enough for about 2 hours of operation after the first stage rocket shuts down). There was one other experiment being done on this mission. I wanted the parachutes to be mostly automated, so that they didn't open too soon (and snap). I came up with some easy numbers to program in: 300 and 0.3. 300 is the number of meters from the ground before the chutes fully deploy. Unfortunately the next option is 50m which may be a bit too close. 0.3 is the atmospheric density when the chutes first release. That density should release the parachutes at just under 6 km, but which time drag should have slowed us down to under 300 m/s and thus safe for deployment. With the science gained I unlock Space Exploration and get the 2HOT Thermometer, the first instrument that can transmit multiple times. With 16 science left I am so close but not close enough to unlocking Stability (18). I want those radial decouplers soon.

With more experiments it seems to be the center of mass is the issue, the difference in angular drag is likely a red herring (unless it has some effect on a part's center of mass) The goo container's center of mass seems to be very close to where it attachs to the side of the ship. By comparison my experiments keep showing the radial parachutes center of mass to be well outside of the model - experimentally it seems like it is between 3 and 4 times it's own thickness away from the attachment point (if you floated a dot where the parachute's center of mass was a kerbal could safely stand in the space between the parachute and that dot).

I'm trying to understand something about the physics simulation. There are two parts, the radial parachute and the goo container. Both have a mass of 0.15, yet in game it behaves as if the radial parachute has more mass. First some experiments to try: Build a ship with a radial parachute on one side and a goo container on the other. Under thrust the ship will tip toward the side with the radial parachute (even with moderate SAS torque). Build a tower out of girders and put radial parachutes all down one side and an equal number and placement of goo containers on the other. No matter the alignment it will always tip over toward the parachutes as soon as it spawns. I looked into the part files and the only difference I could find was angularDrag. The goo is 2 while the parachute is 3. This would explain the ship tipping, the parachute is creating more drag and pulling that side of the ship down. It might also explain the tower, perhaps when it spawns the small movement in which it 'settles' is enough for the imbalance in drag to tip it over. But if you continue flying the ship out of the atmosphere it gets weird. Even without an atmosphere the ship still wants to tip toward the parachute when under thrust. Even if you first use time warp to remove all rotational velocity as soon as thrust is applied the phantom mass imbalance kicks in. Can someone help me understand what is going on? Could the mass center of mass for the parts be different (meaning the 0.15 is farther away from the ships center on one side, moving the ships center of mass in that direction). The parachute is much closer yet it seems to be the one shifting the mass toward it.

JebOne - 49.4t - 50 science JebOne has a lot working against it. With the minimum tech tree unlocked the only way to get science is with the Goo container. I have no batteries or solar panels. The charge in my Stayputnik will last just under 6 minutes. I can't use the much lighter, much more efficient LV-909 engine because it can't generate power. And I need to carry about a ton of fuel in my last stage to run the 1.25 ton 'generator' I'm carrying. With all these challenges I think Jeb is the right name to give to this probe. So JebOne weighs in at 49.4 tons on the launchpad - the 1.5 tons worth of girders being carried on the 2nd stage certainly didn't help after I'm already lifting what is essentially a 2 ton electrical generator strapped to a ship into orbit. With my limited tech and need for science I can't really avoid it without spamming low altitude stuff. It's packed with 6 goo containers and a pair of parachutes. I launch it into a high Kerbin orbit (87km x 267km) to get as much Goo science as possible. The circulation burn helped to recharge the internal battery but after the deorbit burn I still needed to charge again at 80 km to keep the core from fizzling out. I chose to use that burn to speed up my descent, since I was still losing charge fast and I depleted more then half my remaining fuel to get the internal battery back up to 100%. A little thrust before landing helps slow to below 6 m/s and gently touch down without breaking anything. With my 50 science I'm unlocking Science Tech so that I have batteries and the Science Jr.

Keep in mind that in real life most space stuff isn't reusable simply because of safety issues - it costs hundreds of millions of dollars for a launch and lives are on the line, do you want to risk it all to a part that has been smashed through the atmosphere at Mach 20 with 1500°C flames of plasma whipping at it? (and then probably banged around by a recovery helicopter and gunked up with desert sand or salt water) The space shuttle was something of an oddity and while part of the blame can be laid on military and congressional requirements (like the huge delta wing needed for covert military missions) it was never really economical - you could literally buy a completely new rocket for less then what it ultimately cost to refurbish the shuttle for each launch (for example over 30,000 heat resistent tiles had to be inspected and replaced by hand since even a single worn tile could easily cause a Columbia like disaster). The Mercury, Gemini and Apollo spacecraft all landed and where recovered except Liberty Bell 7 but never flew again because there was no economical way to ensure everything was good for another mission. In space you can't call for a tow, everything has to work or you die. Even the Soviet Union, who right or wrong gained some reputation for stretching safety and being short of dollars (post-Soviet Russia has been especially hurt in the budget department) didn't reuse the Soyuz capsule after recovery and so was essentially throwing away several million dollars worth of hardware.

The description for the Stayputnik says "The built-in batteries should keep it going for about 10 minutes". Of course the actual battery life is considerably less since the internal power stores 10em of power and like small probe cores it consumes 1.7em/min for barely more then 5 minutes of operation. And that got me thinking. First the stayputnik comes very early in the tech tree - you can get it even before batteries and will almost always have it before solar panels. Second is that it is the single 'useless' probe core, in that once you get other cores it has no specific advantage (and a big disadvantage in that it only has one stack attachment point). The HECS and OKTO are versatile for 6 and 8 way mounting, the 2 RC cores are useful for automating full sized spacecraft. The OKTO2 is the lightest core and the QBE has some mounting advantages and it has an incredibly high impact rating (I've designed a super-micro probe in the past which relied on that). I would suggest two minor changes to the Stayputnik that would make it match the descriptive text and provide a reason to choose it over other cores. First change the internal battery capacity to 15em and more importantly reduce the consumption rate to 1.5em. This gives the Stayputnik a slightly better electric consumption compared to other cores and thus a reason to use it in specific situations. It also helps it better fit in early in the tech tree - it now really does have 10 minutes of power without any other batteries (enough to last a suborbital flight and still have a charge when it lands), and before getting solar panels it will last longer then the later probe cores on batteries alone.

I will try to answer this question the scientific way with my new career file. A career space program without kerbals, because space is too scary.

The day has finally arrived, the first launch of the Kerbal Space Program. Lanlan Kerman enters the capsule and prepares for liftoff. After a launchpad check in the engine is started and the rockets lifts off the pad toward the sky. I'm going up, things are going...ok I guess. I hear a lot of rumbling. Why is the ground so far away? Am I going to fall? What if I'm stuck here??? I'm starting to come in. IT'S ALL BURNING! Ok so maybe sending kerbals into space isn't a great idea but what alternative is there? The mission collected 65 science, that's just enough to unlock Basic Rocketry, Survivability and Flight Control. That gives us the Stayputnik Mk. 1. We don't need kerbals brave enough for space, we can send machines instead! Ok, so this is going to be a career file (I've documents my other careers here and here, warning they are pic heavy) using only probes, no more manned missions now that I've conveniently unlocked the absolute minimum tech needed for unmanned flight with no science left over. My goal is to get at least 5000 science (that's about half of the tech tree) but if things go fast I might try for the whole thing. Like in my last career I will avoid landing on the Mun multiple times to harvest science. I want to see how far I can get making only one landing on the Mun and Minmus. I'm also going to try to stay within the spirit of these being probes and not just spaceships with a probe core for a cockpit, so I won't be making anything heavy enough to warrant Skipper or Mainsail engines. And if you are interested in the manned mission from above: After reading a post I wanted to see what science could be done with just probes, to see how 'useless' they are. The Stayputnik is the first probe core you can get, and it's easy to see that going through Survivability is the cheapest way to get it (5 + 15 + 45). To get exactly 65 science I examined my previous mission logs and as it turns out there are several routes. My choice was exactly one EVA and one crew report from 5 biomes (surface, upper & lower atmosphere, low & high orbit) plus one surface sample and make it a suborbital but not orbital flight to get a total of 65.1 science. There where some alternate combinations by taking low orbit EVAs over more then one biome and skipping high orbit, or by also getting points for a full orbital flight but I decided those where too finicky. Done in the correct sequence I knew the high orbit strategy could be done correctly in one take without luck or guessing or even piloting skills (crew report on pad for surface, eva on ladder for lower atmosphere, then launch and do crew report for lower atmosphere and repeat for upper atmosphere. After engine cutoff and above 40km do safe EVA for upper atmosphere, then coast into low and high orbit doing report and eva for both. Finally land and do eva on ground and collect soil sample. My only variance was I saved some fuel so I could charge up and transmit the last crew report instead of storing it). I did want a more cowardly kerbal but Lanlan was the most cowardly one available for hire. Career Summary Missions: 16 Science: 7338.4 [table=width: 800] [tr] [td]Name[/td] [td]Launchpad Mass[/td] [td]Science[/td] [td]Mission[/td] [/tr] [tr] [td]JebOne[/td] [td]49.4t[/td] [td]50[/td] [td]Goo in Kerbin orbit[/td] [/tr] [tr] [td]BillOne[/td] [td]12.71t[/td] [td]101.3[/td] [td]Materials lab above Kerbin[/td] [/tr] [tr] [td]BobOne[/td] [td]23.35t[/td] [td]259.6[/td] [td]Mun flyby[/td] [/tr] [tr] [td]BobTwo[/td] [td]23.3t[/td] [td]331.8[/td] [td]Minmus flyby[/td] [/tr] [tr] [td]GeofminOne[/td] [td]29.67t[/td] [td]282[/td] [td]Mun landing[/td] [/tr] [tr] [td]GeofminTwo[/td] [td]29.67t[/td] [td]352.5[/td] [td]Minmus landing[/td] [/tr] [tr] [td]TomvinOne [/td] [td]13.45t[/td] [td]1130[/td] [td]Kerbin system orbital survey[/td] [/tr] [tr] [td]Dudvey X[/td] [td]9.9905t[/td] [td]60.6[/td] [td]Atmospheric test run[/td] [/tr] [tr] [td]Lemgun X[/td] [td]9.962t[/td] [td]86.9[/td] [td]Challenging Mun landing test run[/td] [/tr] [tr] [td]Lanfield X[/td] [td]9.996t[/td] [td]511.3[/td] [td]Minmus and back test run[/td] [/tr] [tr] [td]DudveyOne[/td] [td]9.9905t[/td] [td]594 [/td] [td]Duna landing[/td] [/tr] [tr] [td]LanfieldOne[/td] [td]9.996t[/td] [td]973.2[/td] [td]Duna flyby and Ike landing before return to Kerbin[/td] [/tr] [tr] [td]DudveyTwo[/td] [td]9.9905t[/td] [td]629 [/td] [td]Eve landing[/td] [/tr] [tr] [td]LanfieldTwo[/td] [td]9.996t[/td] [td]1084.2[/td] [td]Eve flyby and Gilly landing before return to Kerbin[/td] [/tr] [tr] [td]LemgunOne[/td] [td]9.962t[/td] [td]318[/td] [td]Dres landing[/td] [/tr] [tr] [td]LemgunTwo[/td] [td]9.962t[/td] [td]574[/td] [td]Eeloo landing[/td] [/tr] [/table] Ask any questions you want, I'd be happy to answer or clarify anything. Comment or click the star if you like this thread.

Yes you can go to the Mun (free return or otherwise) without establishing an orbit, timing is important (and critical if you want free return) unless you want to waste a lot of fuel. This was actually how I frequently got to the Mun in the demo - I hadn't really gotten the hang of making a good orbit (I wasn't even at the gravity turn stage) so I would frequently get on a suborbital trajectory and then instead of getting a Kerbin orbit I'd make a direct burn for the Mun somewhere on my suborbital path. Of course this technically meant that I had a Kerbin orbit for a period during the burn, it just wasn't a very round one or at any predetermined altitude.

Stone 1 This will be the last mission in this career for a while. I intend to come back at some point and tackle the engineering challenges of phase 5, but at the moment those (part from the LV-N restriction) are basically show off sandbox missions and that's not really what I've grown to like. Until .24 comes out (at which time I will do a new career with money and reputation, in hardmode if it has been added to the game) I do have other ideas for careers, like playing with mods for the first time (kerbal life support, FAR, deadly reentry and possibly any others that are focused on adding challenges) but I also have an idea for a shorter career I will probably pickup and play. The goal of Project Stone is an orbital gravity survey of all of Jool's moons. Stone 1 uses the same hardware as Icarus 1 and Ice 1. While it may have failed to reach Moho it is a capable spacecraft. I did make some minor modifications, I removed the landing legs (at the end of the mission I regretted that) and replaced the double-c with a barometer. Since Bop and Pol have both been explored and had their gravity mapped out this will just be a mission to Vall, Laythe and Tylo. Since the second mission of phase 5 involves a major operation on Laythe I intend to visit there last, I can easily aerobrake into a stable orbit so that the probe can later be used destructively to gain some data on how Laythe's atmosphere affects descent profiles (an accurate landing will be required for the manned mission given the small amount of land). Reaching Jool on the 3 radial tanks the aerocapture is set to try and put us close to Tylo's orbit. Adjustments start 17 hours after capture as we pass our orbits AP and make a plane change for 194 m/s to match Tylo. This plane change also lifts our PE out of Jool's atmosphere for free. As we swing around for a second orbit we setup another burn, this time for 158 m/s to bring us on a low pass by Tylo to collect data. Since we also want to visit Vall we might as well do a gravity assist that sends us there for free. I don't even know why I need the big fuel tank. We pass by Tylo and take some readings. Then we just coast over to Vall. 15 minutes outside of Vall's SOI we need to make another burn for 537 m/s to setup an encounter with Laythe in 6 hours. This survey has gone very fast, we'll be at Laythe within 3 days of the initial Jool aerobraking. Aerocapture at Laythe occurs as Jool is setting, while our approach to circulate comes as the sun is rising. Stone 1 will remain in orbit until it is needed by Project Garden. Project Stone completed Made orbital gravity measurements of Tylo, Vall and Laythe. 560 science gained

Yes, you can discover things by examining the Science Jr in Munar orbit or the orbit of other bodies, including the sun. The results will even vary depending on if you are in high orbit or flying closer to the surface (you must be very close to the sun to learn something you didn't learn from a higher orbit). The science lab doesn't find any science by itself. If you bring data or experiments to the lab then kerbals can 'process' the information in order to gain a higher transmission value. However if you have kerbals you might as well bring the data back with you for 100% credit. The science lab can also be used by kerbals to clean and restore the one-use experiments like the Science Jr. and Goo container. So you can use a Goo container, take the data, then dock it with a lab and the kerbals inside will restore it for another use. Finally to get kerbals into the lab use the same method as capsules, while on EVA press F to grab the ladder then climb down to the hatch and press F again to board. To leave the lab left click on the hatch to see a list of kerbals inside and click EVA for the one you want to leave.

Dust 2 Using the same mission hardware as Dust 1 my other kerbonaut Gregfield is going to make my first career manned visit to the Jool system (I went there once trying to land on Tylo with 10 parts, was 500dV short) and my first visit to Bop and Pol. You've already seen how this gets into space, setting up a transfer to Jool isn't very hard because Jool has a massive sphere of influence that ensures anything that comes remotely close will have an encounter. Cost of the injection is 1966 m/s which uses up the transit stage, the rest of the mission will be flown with the capsule and fuel pods. After leaving Kerbin's an adjustment is combined with a plane change to help bring me closer to Jool's inclination and lower my PE. Unfortunately I did make a mistake I've made in the past and instead of setting my PE to 134 km I set it to 134,000 km. So once I enter Jool's SOI it cost another 192 m/s to lower my PE to 120.6 km for aerobraking. With Jool's massive SOI it will still take 9 days to reach the atmosphere. My aerobraking goal was to get my AP around Pol's orbit. I'm not too far off at 195,000 km but I do have a big inclination. With my inclination close to Bop's I decided to go there first. It helped that I could reach it with a course change right after aerobraking allowing me to get there in less then 1 orbit of Jool. Another 487 m/s for that burn. There's something off about Bop. 1000 m/s to brake. Like Gilly Bop is not a normal round moon but an irregular captured asteroid. The braking used up the fuel pods so they are released. I land on a tall mountain with an incline, but the low gravity combined with 6 landing legs seems to let me land without tipping over. After setting the flag I go on a little trip to investigate a piece of debris I can see about 1 km away. Unfortunately it turns out the reason it survived impact was because it actually glitched into the terrain. I launch back into space and leave Bop's orbit. From there reaching Pol takes some more time. I correct my inclination but I'm now in a slightly lower orbit then Pol and not quite in the right place to reach it. It takes almost 2 orbits around Jool (at 6 days each) to get into position. Fortunately it only costs 118 m/s which is good because I'm starting to run low on fuel. I've figured I need to budget at least 1500 m/s to get home and I've used the ship's blueprints to scribble down how much dV I'll have for each 10L increment of remaining fuel. I draw a big line between 80L and 70L marking the cut off after which I may not have enough to get home. With my orbit now much closer in shape to Pol's it only costs 128 m/s to capture. Deorbit is another 100 m/s followed by more fuel to land leaving me with 94.5L. The surface of Pol looks dangerous, I have to be careful where I land. Gregfield makes some important observations for the scientists back on Kerbin. After taking and leaving Pol for Jool's orbit again l have 82L of fuel. The trip home will take 1427 m/s leaving me with a small margin left. I reach Kerbin with just over 8L in the tank and half a supply of monopropellent left (or about 300 m/s in total after spending about 6700 m/s on the mission) Project Dust completed Collected samples from Bop and Pol 4154 science gained

Hmmm. Perhaps I need to investigate this.

Either with a lot of experience or mechjeb you can fly it 'perfect' by constantly adjusting the throttle and turning to match your ascent speed. But flying straight into an orbit (continuous thrust) is frequently not the most fuel efficient way to do it in KSP because of how the physics work and the unique size and properties of Kerbin. Even in real life some rockets (like the space shuttle) use two burns, a long one to reach a suborbital path, and a second burn at apoapsis (AP) to circularize. I'm not an expert at getting orbits but I have picked up enough to do it relatively efficiently without having to know a lot of numbers or change the throttle. My method isn't the best possible method, but it is pretty easy to do and gets much better results then going straight up. First I start with my TWR. With .23 you can tweak the maximum thrust of engines. I take the initial mass of the ship and work out the thrust % so that each stage starts out with a TWR of about 1.44 to 1.5. By preseting my engines like this I can just put the throttle at full and I should avoid drag issues while still wasting as little thrust as possible (the slower you go the more time gravity has to pull you down). For my ascent I monitor my velocity: At 250 m/s I should be between 10-12km and I should turn 23 degrees east (half way to the next big notch). At 500m/s I should turn another 22 degrees (now at 45 degrees). At 750 m/s I should turn another 23 degrees and be looking at my map and hovering the mouse over the AP to see what it is. At 900-1000 m/s I should turn again to one or two notches before the division between the blue and orange part of the ball and get ready to stop my engines when the AP reaches my goal, which is between 71 km and 80 km depending on how big of a launch vehicle I'm using. Once I've stopped I setup a maneuver node at the AP to circularize my orbit. This should cost about 800 - 1200 m/s, usually closer to 800. The last burn to circularize doesn't need any tweaking for TWR and can be below 1.5 though you don't want to be too underpowered or you won't have enough time to burn before you start falling back down.

Gravity and speed, depending on your frame of reference. Atmospheric drag also plays a part. From the gravity point of view until you are moving 2277 m/s sideways you are still falling on a suborbital trajectory, which means you must somehow prevent yourself from losing altitude and hitting the ground first. So for every second it is taking you to reach 2277 m/s moving horizontally, you must also thrust at least 9.81 m/s vertically to prevent yourself from smacking into the ground. From the speed point of view 2277 m/s is only the velocity that will keep you in orbit at 80 km. As you lower your altitude the velocity required for orbit increases. So even if you had a special rocket that instantly applied 2277 m/s of acceleration on the launchpad, you wouldn't be at the correct altitude for that velocity to be enough for orbit. So you end up needing additional speed to raise your altitude which circles right back to gravity constantly trying to keep you down.

Dust 1 Project Dust is concerned with collecting soil samples from potential captured asteroids: Gilly, Bop and Pol. Because they are in opposite directions transfer wise I decided to split it into two missions, one inward to Eve and one outward to Jool. Both will use the block II capsule design though I had some other thoughts along the way. For Jool I considered the idea of carrying project stone along with me. I even worked out a weight balance system so that under one pod it would carry an ion powered probe to explore Jool's moons and the other 2 pods would have equally weighted science and fuel packages. I also considered a similar layout for Eve - Ice 1 would have been carried to orbit on the same heavy booster, saving a launch. However in both cases I ran into concerns over how much fuel would actually be needed. I had some estimates but they contained a lot of guesses for how much transfers would cost. When I examined worse case scenarios the manned missions always came up short on fuel which was unacceptable. I also had a seperate idea for cheaply reaching Gilly. The core block II capsule (without the fuel pods or transfer stage) weighs just under 3.4 tons meaning it could be launched on the same light booster as the Icarus 1/Ice 1 probes. That capsule has a lot of delta-v, just over 3000 m/s, and I was trying to figure out on paper if gravity assists and aerobraking could make it possible to reach Gilly and come back. However I found a lot of unknowns regarding a cheap transfer to Gilly and coming back from Eve was a real problem - at the optimum time it is relatively cheap but it gets very expensive very quickly. I had no intention of orbiting Eve for half a year waiting for a transfer window. Ultimately I came down to using the full transit stage even though it might be overkill for the Gilly mission. I was using the heavy booster anyway so I might as well not waste the weight allowance. I also decided on going to Gilly first, mainly because the transfer window was first. The launch on the heavy booster should be pretty straight forward by now. Rayford will be piloting this mission and I'll turn things over to Gregfield for Jool. I'm going with a mid course correction transfer again. 1050 m/s out and with the small inclination difference between Kerbin and Eve that puts it close to an encounter already. Like always the orbital booster is fired to give just over 100 m/s of free delta-v. That works out nicely when combined with the delta-v in the transfer stages radial pods, since they will run out just as the injection burn is completed. The seperation of the booster happens in an interesting place - below from left to right you can see markers at the Reach 1 landing site, the VAB and finally the launchpad. In deep space a 28 m/s correction is done and we arrive at Eve 36 days after leaving Kerbin. Aerobraking is high at 68 km - I just want to slow down enough to enter orbit around Eve with the AP out near Gilly. This is the first time I've ever brought a Kerbal eyeball out to Eve so I make sure to take a good look. Now there where some issues with my orbit. I was not aligned with Gilly and was actually well inside Gilly's orbit. But I also also orbiting Eve retrograde which was an issue. After 4 orbits I have an opportunity to setup an intercept. But remember that Gilly is coming counter-clockwise and I will be meeting it coming clockwise, essentially a head on collision. Entering Gilly's SOI I throw away the transit stage even though it has 45L of fuel left, I want as much TWR as possible as I start trying to slow down. I eventually pass by Gilly but my exit point keeps getting extended the slower I go. Eventually I finally fall out the other end of Gilly's SOI but by that time I'm doing something interesting with my orbit. After burning most of the 3 fuel pods I am now reversing course and catching up with Gilly. Now I'm burning to catch up with Gilly from behind. I am now in orbit around Gilly moving at city speed. It really doesn't take much to deorbit (15 m/s) so I still have fuel left in the pods. It takes ages to descend so I actually use RCS to push myself down a little fast. Landing is simply the opposite, I use RCS to slow down. It actually takes a while to get the ship nice and settled. Eventually SAS has to be turned off because even that torque is causing the ship to shake, there just isn't enough gravity induced friction to cancel it out. The ladder is not needed, movement on Gilly is by jetpack only. Rayford gets the samples we where after but not without a bit of difficulty in the low gravity. Escaping Gilly and getting back into Eve's orbit isn't really an issue. Pointing the rocket up and thrusting for a few seconds is all that is needed. I got a nice surprise with the return cost, only 1169 m/s. Until now I had been holding a lot of fuel to guard against the possiblity of a 2400+ m/s cost if Eve had traveled enough out of alignment with Kerbin. There is one final experiment I wanted to conduct though it is not entirely risk free. I want to check if the fuel pods can be ejected with the landing gear extended and the engine on. I have some small concerns that the fuel pods could catch against the end of the landing legs. At this stage I don't need the legs anymore so the risk would be a chain reaction that resulted in the fuel pods coming back at the capsule itself. The experiment goes fine, the decouplers produce enough force to easily clear the fuel pods away from the ship. The rest of the return is uneventful as I have a literal ton of fuel (1.05t) left for any course changes. I pass by Gilly (but outside it's small SOI) again on my burn away from Eve. Rayford takes one last look. A total of 1889 science appears to have been collected. First of three objectives for project Dust completed Landed a kerbal on Gilly and returned with samples Performed a backwards capture 1889 science gained

So Apollo 8 meaning you did a few orbits of the mun and returned. If you know how to do your transfers and captures you should be able to do it with the same amount of fuel but it is close. An easier one is if you have a direct ascent Mun lander, which shouldn't have any trouble landing on Minmus.

Sidenote: Block II J-Capsule The manned missions for phase 4 are reusing the well tested and well liked capsule design from Martian 1 and Tyson 1. The landing gear design is getting a bit of work though, with a block II design that includes 6 landing legs. I usually use 4 legs but here that would interfere with the pod mounts unless the legs where moved closer together (which would make it easy for the pod to tip left or right). 3 legs would require 1 leg under the ladder which would require ladder modifications. 6 legs works out fine and also makes up for the fact that I'm using the probe lander legs instead of the normal sized ones. Impact on delta-v in minimal, the pod still gets over 3000 m/s. The second addition is the easy development of new R-Type pods (range) which simply drop the complex science components of the previous pods and extend the fuel tank. These tanks add another 2000 m/s and with the new landing leg design the capsule can land with or without the pods. Block I capsule used in Martian 1 and Tyson 1 Block II capsule Block II capsule with R-Type pods The whole thing goes on the modified transit stage that was tested with Icarus 2. This transit stage adds another 1900 m/s (900 m/s from the radial tanks, 1000 m/s from the core). Finally it is mounted on the original heavy booster. With the shortened transit stage the ship sits even lower, putting the upper stage just above the booster. All the original clamps on the transit stage and booster can still be used to tie down the capsule.

Ice 1 As I've mentioned phase 4 "Inquisitive Minds" is probably not going to be as interesting (particularly the unmanned missions). I'm going to be mostly reusing hardware from phase 3 so research and design costs will be close to zero. There will also be no nuclear engines, I really need to save up the LV-Ns I have budgeted for the big engineering challenges in phase 5. With the tech tree already unlocked the knowledge I'll be gaining will mostly be in advanced transfers as I tackled a return mission from Gilly, a trip out to Eeloo and a lot of movement around Jool's moons. Just as Icarus provided some key data that will be used in one phase 5 project these missions should help in planning the requirements of the other 2. The first mission in this phase, Project Ice, really brings home a comment I made a while back when I said that I seriously under estimated the speed with which I would complete the tech tree. When I was coming up with these missions I was trying to put this one far enough along that I would have the Double-C Seismic Accelerometer unlocked (I was even concerned that Project Berry would come too early for me to have a probe core). Instead I'm starting this phase with the entire tech tree unlocked and I've had the accelerometer since I went to the Mun. The R&D reuse on this mission is hopefully going to restore some honor to the Icarus 1 design. It was light and low cost to build and packed 5000 m/s for transit with a 1600 m/s versatile lander. The fact that I encountered serious delta-v inflation on the way to Moho (in particular I learned that there is a huge delta-v difference in the exact approach used to its orbit) shouldn't be allowed to tarnish the design. So to get to Eeloo I will be reusing the design. Not a new ship based on the old design, but an exact copy. Only the name plate and the data programmed into the probe core differentiate Ice 1 from Icarus 1. I should have a large safety margin for transit (1000 m/s) and the radial tanks should take me through the injection burn almost exactly. One month into the new year Ice 1 is launched into the night. I'm going to see what results I get performing the injection on the same day instead of calculating the exact orbit for the optimal burn. The mission plan itself is just a sheet with my injection angle (I think I described before how I just hold that up to the screen to get a rough idea of where the node should go) and the dates and delta-v for injection and correction. The injection burn will be for 1980 m/s at about 112 degrees from prograde which puts it squarely on the dark side of Kerbin for the entire burn. I'm only running one mission at a time so as soon as the ship is out of Kerbin's SOI I plan the course correction 100 days in the future. It turns out to be very easy to get an encounter for just 164 m/s. After 330 days the probe finally arrives at Eeloo, the farthest planet (combined with the fast forward 1 month to reach the launch window that puts the mission at almost 1 year in total). The capture burn is another 1623 m/s plus a bit more to smooth out a 40km x 50km orbit. Orbital science is done using battery power, out here the solar panels are operating at 50% so the probe needs to take breaks to recharge. For landing the surface seems pretty uniform. The brown lines might be interesting though I'm not sure if a precise landing could be made on them or if it would be safe - those could be jagged rocks for all we know. The only other notable feature is a crater so a landing is planned to set down there. Fuel for the deorbit and orientation to the landing zone are done using fuel from the big tank. After that the tank is carefully released and the probe thrusts away. With the altitude at 21km I don't want to be dealing with releasing the top mounted fuel tank closer to the ground where it could pose a danger of colliding with a fragile part of the probe. There is plenty of fuel left for landing, though the ground is very uniform which makes it hard to judge how close the probe is to the surface. No scatter (rocks) can be seen. I take the landing safe and slow. 1.2 km from the surface I can finally see the probe's shadow, visible as a small dot above and a little to the right of the landers top leg. After a gentle landing the probe can complete it's mission. Some interesting activity is detected which could provide the answers kerbal scientists where looking for. This was a pretty straight forward mission to fly (49 minutes real time, a lot spent at maximum time warp), the mid course correction being the critical section for success. Project Ice completed Landed on Eeloo and transmitted seismic readings 555 science gained

The physics simulation works by taking a certain amount of time (the delta-time) and figuring out how much everything will move in that time and then figuring out if anything has collided (and some more advanced things like drag, joint tension and such). So if you have an object moving at 10 m/s and the game chooses to calculate a delta-time of 0.1 seconds it will move the object 1m forward and then after check to see if it's touching anything. The accuracy of the simulation depends a lot on how small the delta-time is. If the delta-time was 10 seconds then the object would move 100m before checking to see if it was colliding with anything, so most of the time the object would be able to just pass through other objects without hitting them. This can actually happen in the game when flying a ship at very high time warp, if the game doesn't catch it in time and automatically lower the time warp you can pass right through a planet. Other then objects passing through each other there are more subtle effects when the delta-time is too big compared to the level of detail required. Effects like joints and friction where many forces are interacting at once need to move in small steps to ensure all the forces get balanced out nicely. If you try to move them in big steps you get violent jerky motion as parts bounce off each other and often explode from the large forces being applied all at once. KSP doesn't use a fixed delta-time for each frame. Like with the graphics it will try to calculate as many physics frames each second as it can, leading to a smoother, more accurate simulation. So the delta-time will be as small a the game can make it. but the more parts there are to calculate the more time it will take, leading to a larger delta-time for each complete frame. The [Max Physics Delta-Time per Frame] is a safety net. It is the highest delta-time the game will use. So if it takes 0.2 seconds to calculate one frame (and so the delta-time would have to be 0.2 seconds to make the game move at 1x speed) but the [Max Physics Delta-Time per Frame] is set to 0.1 seconds then the game will use the maximum value instead. This means the game will appear to run in slow motion - for every 0.2 seconds that pass only 0.1 seconds of game time will be calculated. In summary: [Max Physics Delta-Time per Frame] is used to balance the accuracy/stability of the simulation with the speed of the simulation. Making [Max Physics Delta-Time per Frame] a bigger number means the game won't slow down on slower computers, but may become less accurate. Making [Max Physics Delta-Time per Frame] a smaller number means the game will always remain accurate but may slow down as you make bigger ships.

Icarus 2 This is a follow up to the failed Icarus 1 mission which crashed into Moho when it arrived without enough fuel for the massive capture burn. I didn't want to use ion power for time reasons (see ion design above) and that meant a chemical rocket which would immediately go over the 3.4t allowance of the light booster. I didn't really want to invest in the R&D for a new booster for this mission, over budget as it already was, so the heavy booster was picked. While that left plenty of weight allowance to design something new I decided to first see if there where any existing designs that could be pulled up and used to avoid new design and testing costs. One design that fit the bill without any modification was the center booster/transit design used in Cheese and Mint. Seen here without the small tail portion used during lift off. There where several downsides to this design however. First was that it was very tall which could pose stability issues during launch. It was also based on older technology (before fuel lines) and so it had to carry multiple LV909 engines used in succession, driving up the material cost. Finally there where a few unknowns with stripping off all the radial hardware. So instead of going back I went forward a little. For phase 4 I am going to be heavily reusing hardware from the current phase 3. One piece of reuse that was already in the final stages of consideration was a cheaper conventional engine variant of the nuclear transit stage used in Tyson 1. The fuel duct system, radial clamps, payload tie-downs and top mounting point optimized for a Rockomax 48-7S would all be the same, but a much cheaper LV-909 would be substituted for the expensive LV-N atomic engine. Since the probe used the 48-7S it would fit perfectly, the optimized mounting point even allowing the probe to launch facing right side up. The unmanned Icarus 2 will be used as a practical test of the modified transit stage, allowing some of the ground tests to be cut. With the heavy booster the launch is the same as Martian and Tyson. The same injection burn is done as Icarus 1 only using the bigger transit stage. I'm lacking illustrations but I changed my mid course correction which is done once I reach the 9 o'clock position around the sun (assuming our orbit is anti-clockwise when viewed from above and Kerbin is at 12 o'clock). I found I had two similar corrections I could make that both cost about 1800-1900 m/s. The first was very close to the correction I made with Icarus 1 which would take me to a direct meeting with Moho at 3 o'clock after I swung around the sun. This encounter would be on the original ~40 day schedule and let me land on Moho while Tyson 1 was still in transit back to Kerbin. However I found a second possible correction that seemed better. This correction would better align my inclination with Moho, so that when I eventually encountered it I wouldn't be coming in at a sharp angle that needed thrust to cancel out. This alternative course would require me to take an extra trip around the sun - I would continue without correction toward the 3 o'clock position where I would miss Moho but instead make a course change that lined up their planes and setup an encounter at the same time on the next orbit. The longer trip would take 86 days in total but bring my capture delta-v down to 3600 m/s, though I needed to spend more delta-v then I should have to lower my PE first. If I had set that up earlier I would have saved some fuel. The Kerbin to Moho injection burn, the orbital correction burn and the PE correction burn are all done using the new transit stage (I need to give it a proper name if I reuse it). The final capture is done using the original probe's tank. Sadly the only shot I have of the correction, taken shortly after it was made. We burn into a nice orbit around Moho. I want somewhere flat to land. Orbital observations don't really help me figure out what areas are bad to land in. If Moho is bumpy then the elevations must be much lower then planets like Duna - many small hills instead of large mountains. Without any other informed options I opt to land in the middle of a crater where most inclined should have been wiped out. There is one good candidate on my light side orbital phase. With some fuel left in the big tank I should be ok for landing. After using it up to help kill my orbital velocity I release it and then thrust up a bit so that the tank starts moving ahead of the probe. I am trying to use it to judge the altitude of the landing zone - when I see it crash I'll know how far away the ground is. When it is showing 5.2km and my own altitude is 6.1km it disappears (it is too far away now to see an explosion). Knowing that the ground below is at roughly 900m altitude I burn accordingly. I also look for my shadow but I can't see it until I'm about 300m from the ground. However I have plenty of fuel so the last 250m or so are made at under 15 m/s. The landing is a bit off balance, leading to another instance of reaction wheel torque holding the ship on 2 legs with a solar panel dangling inches from the surface. Altitude at landing zone is 922m. Once on the ground the Icarus mission can finally be completed by taking readings. The huge amount of solar energy being recieved means the batteries are not required, I can transmit continuously with solar power. Even with a small set of instruments we can learn a lot about Moho. Project Icarus Completed Landed on Moho and took temperature and other readings Learned more about Moho transfers 210 science gained

I've been there twice now (crashed once). There are two things I've figure out so far to help reduce your delta-v requirements. The first is common to any planet and it looks like you did it, which is try to get your PE as low as you can before you even enter Moho's SOI. With tweakables you can lower your engine output to as little as 5.5% (this can be changed in flight, not just in the VAB) which gives you the fine control to adjust your PE while still days or weeks away. The second thing which will probably shave about 1000 - 1500 m/s off the capture is to try and get your inclination matched up to Moho's for your encounter. If you do it during your mid course correction it will probably only cost 200-300 m/s, though you might need an extra orbit before the encounter. Basically think of it like docking, when you reach Moho you're going to need to zero out the relative velocity and make your orbit match Moho. Now you'll get an assist from Moho's gravity but the ratio of that assist compared to your very high orbital velocity will be much less then you get with other planets farther out. Coming in on an incline means you'll have to cancel out all of that 'vertical' velocity, and your velocity being so high the vertical portion will be high too.