Claw

They were quite epic crashes. Two thumbs up.

I guess I can't guarantee it. I can't tell how much your lander weighs, but looks like you have around 10 struts. The one in the picture has over 30. I was actually looking for another picture that is literally ringed with landing gear. Oh yeah, one more thing I just thought of for you to try before redesign. Right click and lock your suspension. I don't know that it will help, but sometimes it does.

Looks like you need more landing gear. The gravity is a bit higher than on Kerbin so they sink in more. Also, avoid landing on the slopes if you can help it. I'll see if I can find a picture of another lander. EDIT: Here you go. This is someone else's lander.

Yep, all the stuff Kerba Fett said. I have also experienced it as a bug, where I simply right clicked on a tank and then right clicked elsewhere and it wouldn't go away. Sometimes going to map view or back to the space center worked. Another time I did a quicksave and reload. Most of the time when I see this bug, I've been messing with Alt-clicking on parts and it causes the pop-up screen to stick. I don't know if you were doing any of that, but might be something to avoid (or check if your keyboard is stuck).

Like Kerba Fett and 5thHorseman have said, sounds like you've disconnected your ship and/or deleted your root part. How can you tell? If the ship parts you are trying to mess with are gray or red, you won't be able to select them individually. Also, if you are unable to zoom or rotate the screen around, you've deleted the root part. The loose pieces will need to be reattached to the root part (as others have said). The root part is the part you first picked when you were making the rocket. If you've deleted it, then you'll need to select a new root part, which will automatically drop itself into the center of the VAB. If your ghost ship is in the way, you might have problems seeing it. If you're not terribly worried about your current design, it might be less confusing to just start a new rocket.

I think that it's a good thing that you're able to clip. Because it's there, you can choose for yourself to do it or not. In this regard, I agree with Kasuha. It's your game, play it how you want. And if it's another person's game, let them play how they want. Personally I only do clipping that's allowed by default in the editors, and there's quite a lot of clipping you can do in there. I find that typically when I clip in this way, I don't usually run into problems with phantom forces or parts spontaneously exploding. I have also found that allowing debug clipping results in some undesirable VAB/SPH behavior. In my experience (if I'm going to use debug clipping), it seems to work out a little better if I turn on clipping, do what I want, then turn it back off.

Muahaha. I was ninja'd while posting and hopefully I've made my point about intuition and theory.

Yes, I fully agree. Hopefully my thought exercise didn't imply otherwise. It was more to illustrate how you can't peanutbutter spread a theory around. But again, if I could employ a partial but instantaneous impulse of dV, my orbital speed just increased. So if I can immediately apply another partial impulse of dV, did I maximize my Oberth? I'm not saying this is correct, I'm trying to illustrate examples that seem intuitive but are not accurate representations of the theory. Because as you said, you're not at the optimal place for the new orbit (after the first impulse) even though you're going faster than you were.

Yes. You don't need to do anything special to harness Oberth. There are ways to go out of your way to harness it, but for the most part isn't necessary. The Newtonian vectors work fine enough in/around Earth when you ignore Oberth. What was throwing people off was that original pure vectors only considered chemical energy, and not the exchange of Kinetic. So they proclaimed you needed vast amounts of dV to get inter-planetary. If you include KE in the vectors, then it's a non-factor. AND YES!! KSP factors this all in. So put your nodes down and enjoy the fact that KSP calculates it for you.

But once I start firing engines, my speed increases. That's the key point of this thought exercise. Does increasing my speed over time improve my ability to harness Oberth?

To be clear, placement of the SAS modules does not affect how well they do their job as rotation. In this manner, placement does not matter. The center of rotation is always around the Center of Mass. This is why some people experience problems when docking a vehicle. As others have stated, ship wobble is because the station is not an ideal "rigid body" structure. Kasuha's example is a good place to start the trial and error process of dealing with a flexible body. Unfortunately there isn't a magic spot to always put SAS that fixes this. The ship can still flex and wobble around whether the SAS modules are near the CoM or out at the ends. Even distribution generally works best because no single place on the station experiences a concentrated bending load, but that isn't always a sure fire fix. Making the structure more rigid helps too. To some extent you'll simply have to use trial and error.

Your exploding ship example is right on. In fact, it isn't even that the retrograde portion is experiencing Oberth. It is "because of" the retrograge portion that you have Oberth. You're litterally stealing it's kinetic energy. (And the opposite is also true.) Again, this is why I dislike examples that stay inside an SOI and discuss things like AP retro burns. They defy intuition and simply confuse the issue of Oberth. And agreed. Dumping a stage in orbit does give a change if any amount of force was used in the separation (i.e. a decoupler).

SOI is a real assumption. It's a way to simplify orbital dynamics, and it's considered a valid assumption. Call it a gravity well if you wish, it's the same idea. It's an artifact of scientific assumption. You can't have a hyperbolic trajectory that doesn't leave the SOI. That's the definition of a parabolic/hyperbolic curve. It runs off to infinity. Now that doesn't mean you have to fly the whole trajectory. Also, I said I agree that you can use Oberth inside an SOI. I didn't use that as an example because the math is more complex, so it makes using a conceptual example overly complicated for posting on a text forum. Also, the OP said he read the wiki and didn't understand. So I was explaining the wiki and focusing on it's explination in an attempt to not get bogged down in details. TWR affects how much Oberth effect you can harness, but Oberth is not dependent on your TWR. It's a subtle distinction. If I somehow had a very high TWR and a very long burn time, the ability to harness Oberth is effected in a similar way as if I had a low TWR and the same burn time. The assumption of TWR effecting Oberth is making a secondary assumption that the same impulse is being applied, which wasn't stated. So if I said, "For a given dV burn, having a higher TWR means I can harness more Oberth" that would be more accurate. This is implicit in the theory, but that's because the theory assumes an instantaneous application of a given dV. But here's another thought. Assume a circular orbit such that orbital speed is unchanging (PE = AP). If the engine is fired at any arbitrary point, ship speed increases. Does this increase my Oberth?

By the way, the Oberth effect is not dependent on TWR. Oberth effect is a theory which relies on orbital velocities and KE exchange. TWR can affect it, but Oberth is not dependent on it. If your velocity isn't rapidly changing, then changes in TWR are going to have little impact. It does have to do with how long it takes you to apply those changes (TWR), but relative to how fast the velocity is changing. If the velocity is changing very slowly (i.e. a circular orbit), then TWR is much less significant.

Sure, I will get on board with this. And I also agree, you certainly don't have to be out of the SOI to see the results of burning at PE before leaving the SOI. Mostly I was trying to avoid adding qualifier after qualifier and delving into the equations, because when people have been referring to changing parameters of an orbit, there starts to become confusing about potential energy vs. kinetic energy vs. chemical energy. When considering the effect for inter-body transfers, it becomes clear that crossing the SOI (when potential energy hits zero) nets a gain in speed that is higher in the new reference frame than the dV applied. Some of the examples I have been seeing simply focus on "why doesn't the speed or fuel efficiency increase when burning at the PE." Also I modified my post. I said interplanetary at first, but the conceptual exercise works equally as well leaving the Mun's SOI and returning to Kerbin's SOI. Burn lower at the Mun and you'll have more (or less) orbital velocity around Kerbin when you emerge from the Mun's SOI. You'll also have steadily higher velocity as you leave the Mun's SOI than if you did the same burn from a higher altitude. To defy the intuition of your burn to 50km example, another weird phenomenon... -From that 75x75km orbit (orbital velocity about 2300m/s), burn prograde 500 dV. You end up with an AP of about 1.35Mkm -At the APof 1.35Mkm (orbital velocity about 950m/s), burn another 500 dV. The craft ends up with a 1.35Mkm x 2.23Mkm orbit. So at this point, 1000 dV has been added. -At the AP of 2.23Mkm (orbital velocity about 1000m/s), burn 500 dV retrograde. The PE ends up inside Kerbin's lithosphere. So how the heck did I add 500 dV at 2.23Mkm (at a speed of 1000 m/s) and it lowered my 1.35Mkm PE way below my original 75km orbit (where I added 500 dV at more than twice the speed)? - (NOTE: I'm not looking for an answer to that.) My point is, this is why I dislike trying to use examples of Oberth inside an SOI. I see wacky examples like this (not necessarily in this thread), but there's so many things going on that it doesn't explain Oberth at all. In fact, if you just look blindly at this example, it looks like Oberth is a complete lie, which it clearly isn't. One has to be careful about setting up experiments based on a piece of an equation/theory, without understanding the assumptions behind it. That's why my explanation focuses on intra-SOI transfers, since everyone quoth the wiki, and that's what the wiki assumes.

This is true, but it's much less due to Oberth effect. It's inefficient to change your orbit by circularizing at intermediate steps. So if you burn at other than the PE, you're basically spending some amount of dV on circularizing. Just like most efficient place to raise your PE is at your AP. Oberth is lower at your AP then anywhere along your orbital path, but it's still efficient here because your potential energy relative to the body isn't going away like when you leave an SOI.

Well, I think you skipped over some of my explanation and just jumped onto a point I was arguing against.

Okay, I've been trying to stay out of this one because it is rapidly blooming, but like the torque question I feel pulled in. I feel like some people are in on this but it's getting mixed up with some of the examples. Please stop using the car example. While it is an excellent example of conservation of momentum, it is poorly constructed as an analogy for interstellar transfer. The car neither achieves escape velocity from the road, nor does it observe exchanges in potential and kinetic energy from the road's gravity well. Also, the frame of reference is wrong. I will avoid using numbers for the conceptual part, because numbers simply provide a specific example to confuse the issue. (For those who feel comforted by numbers, the example at the end will include them.) Parabolic example and detailed proof from wiki. It seems simple enough right? Specific energy is So if I'm exchanging chemical energy for dV, then I must be getting free dV because the equation has Velocity! Well, not exactly. Here is why, and also why many of the examples are lacking a definitive demonstration of the effect. The Oberth effect is primarily obvious during inter-body transfer. If you are trying to execute an oberth effect around a planet (or the sun) and simply changing the shape of your elliptical orbit, you will not see an effect. To benefit from Oberth, you must leave what KSP calls an SOI (in reality, the "gravity well"). Hence why all the Oberth internet references talk about parabolic or hyperbolic trajectories. Those trajectories enter and then leave an SOI. Here's a conceptual example: Scenario 1: Imagine you're in a 75x75km orbit around Kerbin. So now the PE/AP debate doesn't really matter because it's the same all around. Suppose I do a burn prograde to Kerbin's orbit around the sun. The burn is such that the craft just ever so barely manages to escape to the forward edge of Kerbin's SOI so that it is orbiting the Sun just in front of Kerbin. It's no longer orbiting Kerbin, so from Kerbin's perspective it has zero kinetic energy. Also, it isn't capable of falling on Kerbin, so from Kerbin's perspective it has zero potential energy. Now, if I am at this point and I burn directly away from Kerbin, my orbit around the sun will change by the amount of dV that I apply. Also, from Kerbin's perspective the speed away is the dV I applied and the kinetic energy is 1/2 * (dV)^2. Scenario 2: Imagine you're back in that 75x75km orbit around Kerbin. Now if I do the same "Kerbin orbit relative prograde" burn with enough dV to just escape, plus the dV that I applied once interstellar, I've expended the same amount of dV as I did in the above scenario. My fuel expenditure has NOT changed in any way (i.e. I've used the exact same amount of liquid fuel and oxidizer as scenario 1). As I'm leaving Kerbin's SOI and enter the Sun's SOI, my speed isn't simply the extra dV that I applied. It's the converted kinetic energy. So from Kerbin's perspective, I have no potential energy (because I'm incapable of falling back on Kerbin), but my kinetic energy is higher (because in Scenario 1 at SOI crossing my KE is zero). Now, that extra dV that I applied interstellar in Scenario 1 has been multiplied. This is because I transferred more kinetic energy with the LKO burn, which has NOW been converted into velocity. How much higher is the escape speed? Practical Example "I don't believe you!" Well, for those who like experiments and numbers, here's an example you can do in KSP. Make a ship, any ship that's capable of escaping Kerbin's SOI will do. I made a ship that had almost 4000dV in a 75x75km orbit around Kerbin. Scenario 1: Fire the engines while on the back side terminus of Kerbin so that you leave the SOI going forward relative to Kerbin's orbit. Getting an exactly perfect escape velocity is difficult because it's such a narrow speed range, but the burn takes about 935m/s dV. Speed around Kerbin is now about 3200 m/s. This results in leaving Kerbin's SOI (for my test anyway) at less than 50m/s at the edge of the SOI (took several days). The orbital speed around the Sun was about 9340m/s. I then applied another 300 dV which brought my orbital speed around the Sun up to 9640 m/s. So total of 1235 dV spent, and a solar orbital speed of 9640 m/s... Scenario 2: Fire the engines past the back side terminus of Kerbin. This ensures you're leaving the SOI at the forward edge of Kerbin's orbit. How much to fire the engines? At precisely 1235 dV worth. End result, the speed around 3500 m/s. So a gain of about 300m/s from the Scenario 1 burn. Makes sense. Except this time when the craft leaves Kerbin's SOI, it was at 1426 m/s. Solar orbital speed is 10708 m/s. So total of 1235 dV spent, and a solar orbital speed of 10708 m/s. Nearly 1100 m/s higher than Scenario 1. Back to the theory: So now if you go back and do the math. sqrt {1 + ([2 * 3200]/300)} = 4.72 300 dV * 4.72 = 1420 m/s If you compare the final solar orbital velocity for scenario 2 (10708 m/s) with the solar orbital velocity for a (just barely) Kerbin escape (9340 m/s), you'll see that it's 1368 m/s. So not quite the 1420 expected. What's the difference, the 9340 m/s escape velocity included about another 56 m/s. So add that on to the 1368 m/s and you get 1424 m/s. Pretty good test of the theory considering the lack of real instrumentation. Conclusion So yes, in a manner of speaking a craft does get free dV. But it isn't because of some magical change in fuel efficiency, Isp, or slingshot effect. It's because it's conserving Total Energy (which includes Kinetic, Potential, and Chemical energy). This is why it originally confused rocket scientists. Because kinetic exchange during the SOI transfer didn't make sense when you only consider the chemical energy of the rocket and not the conversion of kinetic energy.

Don't feel bad for asking a question. And hopefully you aren't feeling beat down by the community for asking. I personally find it hard to give generic advice because this game is so open ended. But I probably over-post when it comes to a topic I know about. If you are feeling lost and confused, I would suggest slimming down your mods as you (and others) have said. That will probably help us help you a little easier. I don't think there are too many people that browse this forum who have such an array of mods installed. Once you get the idea of the basic game, start adding mods back in. But when you do, make sure you know what you're adding. Like FAR. It changes the aerodynamic model of the game. So in addition to all the menus and information that pops up, you're going to see different performance from rockets. I just started a probe only career, and it's been kinda fun. A manned program tends to be a bit quicker with the science return if you're planning career vice sandbox.

Yes, when you reset experiments you are resetting them. Good to point out though. There is some layer of warnings when trying to take new readings. Hopefully they will implement some sort of "resetting this will lose the data" message with a "don't show me this again." It would get very annoying when in high orbit trying to nail those little biomes to repeatedly warn me about dumping data. Each experiment has locations where it can be done. Some can only be done in atmosphere, some on the ground. When you're storing those experiments in the capsules, you can only store one unique experiment at a time. So you can't store two Mystery Goo samples that were obtained in high orbit around Kerbin (nor do you need to). If you try to enter with an experiment that is already in the capsule (or your EVA kerbal is carrying two), it will tell you it can't hold any more samples. This doesn't mean your science is gone, it means you already have it stored. Just to clarify, only Goo and Science Jr need to be scrubbed. Other science experiments can be reused after collection or transmission. As Dispatcher pointed out, repeating science experiments under the same conditions gives you nearly zero science, assuming you've already returned the experiment to Kerbin via EVA or returning the device. Goo containers and Science Jr containers can only be used once. You can reset them as many times as you like, but once you collect on EVA or transmit, they are done. Also realize that if you take them to the Mun, do the science, transmit, then return them you will only receive the science for transmitting. And any science that you transmit during the trip will not be reflected in the end of flight summary. Transmitting science does not prevent you from performing a subsequent mission to collect and return it later. EVA & Crew reports: You can only store 1 of each. Transmit it before you take another report. EVA and crew reports get 100% science when transmitting. Make sure you have sufficient battery power and recharge ability. Goo containers and Science Jr: If you do the experiment then reset, your last experiment is gone. If you do an experiment and collect on EVA or transmit the data, the device is no longer usable for that trip unless you clean it with a lab. You can look at this thread to see my short discussion of how transmission impacts science. Have a look at the wiki KSP science page that someone linked to above. If you're like me, it didn't make any sense the first time I read through it. Focus on the "Possible activities in different locations" matrix. It shows where you can do each experiment so you aren't bringing the wrong equipment for your mission. Then look at the "Celestial body multipliers" matrix. On this one, don't worry about all the multipliers. But on the last column it shows you what the altitude is to be considered "low orbit." This is useful to keep from repeating the same experiment in the same location. Now you can plan your orbits and such to reach for and obtain science. As for only recovering 1.5 or 3 points per landing, you are probably repeating experiments in the same biomes (if you're doing them at all). Someone earlier posted the biome maps. Once you can mentally map those onto the surfaces in-game, your science will greatly increase. Different biomes at different altitudes (low/high atmosphere, low/high orbit) can net you more science. And finally, if you've lost total track of what science you have done up to this point, go to the "Research and Development Center" and click the yellow "Science Archives" button. You can select and filter down to each type of experiment, situation, planet/moon, or whatever.

When saying "destroys the experiment," I feel I should clarify that it resets whatever science you had in that instrument. It does not destroy the device, except in the case of the Science Jr or the Mystery Goo containers. But the essence is correct. If you are planning on returning to Kerbin, keep the data from your last experiment in the device (or pick it up via EVA) rather than transmitting it. (Again, doesn't apply to one-way probes.)

There are two main ways to get the science after you do an experiment. Either transmitting or recovery. Recovery can be done by delivering the sensor back to Kerbin's surface, or recovering via EVA (then process or returning to Kerbin). You can process via science lab, but none of that applies to one-way probes. Science recovered by transmission varies by type. For example, the gravity scan transmits for 40% of the recovery science value. So if a recovered scan is worth 100 points, you will receive 40 points for transmitting the data. You can often transmit a second time for some small value (in the range of 1 science or less), but further transmissions get you none. To answer your second question, it does not "destroy" follow on science. So if you go back and scan that 100 point science area, then recover the gravity scanner (back to Kerbin surface or via EVA as described), you get the remaining 60 points. Some science (such as the goo canister) are single use, and once you transmit (or recover via EVA) you can't use that canister again. You can bring more than one canister though. Sci Jr is the same way. Those one-use experiments can be scrubbed and reused in a science lab (again, doesn't apply for one-way probes). Most of the other sensors can be reused, but you are still limited by the transmission percentage. Also note, if you are recovering the sensor, then it can only store one reading but you get the full science. EDIT: Yes, this changed in 0.23.

It doesn't always work as expected, and it sometimes leaves spare parts lying around. I find that if I pull off something by mistake, it's easier to delete that piece and undo, than to set it loose in the VAB before undoing. I have also had it attach a second copy if I was slightly moving something but didn't align it quite right, then tried to undo. Sorry, felt like I had to warn. I have messed up many craft trying to "undo".

Also, I think orbiting and intercepting retrograde can shorten your flight time. My first landings on the Mun were retrograde, because it is pretty easy to literally line up and crash onto the surface. The orbital alignment felt much less complex than trying to "meet up and orbit" when I was first learning how.

I usually do the camera clip. It is also handy in the VAB/SPH. Just know that if you are zoomed way in, you might have to zoom out after selecting the tank. Sometimes the little fuel window (or any tweakable window for that matter) that pops up will be off screen, but you can zoom out and click on it.