Aphobius

First of all, it would be a good idea to learn at least the Newton's laws of motion and law of universal gravitation, before trying to understand orbital mechanics effects. But to solve that great dilemma that you have. If you are near (in low orbit) a planet and you have 10000m/s delta-v available. If you make a 2000m/s prograde burn and after a few hours you realize that wasn't enough for what you want to achieve and you actually have to burn all the fuel, so you make another 8000m/s prograde burn. In that few hours you've got away from the planet slowly (starting from 2000m/s) and gravitation slowed you down, maybe you even lost all that 2000m/s and your speed is now 0m/s and after the 8000m/s burn your speed is going to be ... 8000m/s. But if you burn all the 10000m/s from the beginning, while you are in low orbit. You'll get away from the planet much faster, so you'll spend less time near the planet (where the gravity is higher) so the gravitation of the planet is not going to slow you down too much, you might lose like 100m/s, so your final speed is going to be 9900m/s instead of 8000m/s. So with the same amount of delta-v (10000m/s) in the first case your final speed is 8000m/s and in the second case it's 9900m/s. This is not an accurate explanation, but it explains the Oberth effect pretty well to people with poor physics education. EDIT: The Oberth effect is not about the general idea of this effect, the Oberth effect is about the equations that help you to calculate this things exactly. The idea is pretty simple if you have very little common sense, the hard part was finding the equations to calculate this thing exactly, not understanding the idea. EDIT 2: I omit the initial speed on purpose, to make the explanation simpler. But I have to add this, this is the interesting part about the Oberth effect, that gravitational slowing down affects not only the speed that you've got from the burn, but also the speed that you initially had. So let's assume in my example above you had 2000m/s initial speed when you were in low orbit. In the first case you, after the 2000m/s burn, your speed is going to be 4000m/s and after a few hours let's say it dropped to 500m/s, if burn the other 8000m/s that you still have, you'll have 8500m/s. But in the second case, if you burn 10000m/s from low orbit, after the burn your speed is going to be 12000m/s, but since you go so fast and you spend so little time near the planet (where gravitational acceleration is very high), after the same amount of hours from the first case, your speed can be 11800m/s. So with 10000m/s burn, you've got a speed of 11800m/s (considering you are so far away, the planet is not going to slow you down anymore), because you've carried with you a part of the initial speed that you had in low orbit. The values are random and exaggerated but the general "patterns" are correct.

You must define better what "stage" means, because people can put everything in one stage and just use actions groups or right click things and activate them manually. It's pretty obvious separating a part of the rocket would constitute a "stage". But what about using action groups to activate something later? For example if you have a SSTO aircraft and you use the jets first and you activate the rocket later using action groups or even stages .... it's still a Single Stage to Orbit aircraft. You can have 10 groups of sepatrons and use action groups to activate them one by one, without ever separating any of them, each activation would constitute a stage? You have to clarify this. Not allowing action groups or activating things later by right clicking them (so people don't do that sepatron thing I've mentioned above) would make this challenge much more challenging. But you have to state it exactly in the rules. I don't want to waste time with this just to have some unskilled, "inventive" person come and abuse the rules.

Thank you. Unfortunately I don't think anyone else is going to try it. But would be nice to have some competition. My time is pretty far from being competitive, that rocket can be optimized much more. So the ... competition should have just started.

No, we don't.

Here is my entry. I had to use quick load a few times so I've separated the videos. Launch Landing Return 2 Hours, 12 Minutes, 15 Seconds I can do it much faster, but I'll wait for competition. PS: Sorry for the intellectually disabled voice.

This would be much better with a save file that got a station in orbit and we would have to dock to that. That would clear all the confusion.

Nice challenge, but you shouldn't put stock and FAR in the same leaderboard.

If they would try DCS, they would be like "Take-off is too hard, in FSX I've always got it, but in DCS it just doesn't work".

I modified your quote a little, to add numbers to the questions. 1 - It works if you are under 250m from the target (not sure if it's exactly 250m, but if i remember right it's not working at 500m) 2 - They are default parts. 3 - There are few struts, but placed in the proper places. 4 - As I've said, I don't know how FAR is working, if airplanes are slowing down too much when you maneuver that is also a problem.

Video It's too easy.

No cheats I don't refuel it, but I could have done it. EDIT: To be honest "be a better pilot" is the best tip. Kerbal is not really something serious xD. But air refueling is usually hard to do anywhere. Other than that, I don't know how that FAR thing is working, but I had to remove the control surfaces from the aircraft that I'm controlling while docking, so it doesn't accelerate anymore when I control it. (because of that infini-glide crap)

There are very few situations where you have to change your inclination, if you are on the equator (as KSC is) you can launch into any possible inclination. Also when you arrive at a new planet or moon, you can get in any possible inclination (a little harder to control the longitude of the ascending node, but it's possible). EDIT: What you say about not launching into equatorial orbit ..... you just have to launch towards East, just be more precise.

Burn in a direction that is perpendicular to your orbital plane. If you want to match other plane, you have to make this burn at their intersection. But inclination changes are rarely needed if you do everything else properly.

They must be beaten with a stick and sent to school.

Considering what people are discussing here, it seems it still is a serious thing.

What the hell are you talking about? "The classic argument"? In kindergarten or where? xD The current physics don't work with such simple "arguments" anymore. You have the Newton's law of universal gravitation (F = (G*m1*m2)/r^2), you have the second law of motion (F = ma). That puerile "argument" is really necessary? Newton's laws can be considered as puerile as your "classic argument" compared to quantum gravity, but in the context of KSP they are good enough.

I'll not write it's specifications because I don't want to show off.

This picture makes me angry. Because I know some people here might actually believe that Kerbal Space Program can improve the knowledge about orbital mechanics of a person that got a job that requires a physics degree at NASA. (assuming that NASA is not going to hire someone with a physics degree as the janitor) I know the picture is a joke, but I'm sure a lot of people from here are going to believe that it's not.

If you know the laws of motion (simple things like F=ma) and you know how to solve simple mathematical operations (addition, subtraction, multiplication, division). You can easily calculate the motion of a body that is in orbit. I don't say it's going to be accurate. It's not like I want a 12yo to do a Runge-Kutta numerical integration, but he could do a simple Euler integration and he could still observe the patterns in the motion of the bodies. EDIT: Also, saying that NASA didn't knew simple things like this in 1965 is not very smart (some wikipedia link earlier), but whatever makes you feel better about yourself.

How stuff in space worked? There are just bodies that move under the action of a force (gravity), these are no "orbital mechanics", these are simple physics. Even a 12 yo can do some simple numerical integration to observe some patterns in the motion of bodies that are in orbit.

I was honestly feeling like beating the OP with a long stick (literally). But I thought, what the hell is wrong with most of the people on this forum, my head always hurts when I read it. So I've made a little research and found this: Physics education Really? What I wanted to find was that they teach you the laws of motion in the forth grade or so. But a whole nation (I assume that most people here are from the US) that never heard at least about the laws of motion. What the hell? Anyway, now everything that happens here makes sense.

I usually post videos, so I've made a video since it's kinda easy to cheat (by using RCS after the bounce or by just walking xD). I've got only 70.8km in the video, but since it's kinda luck based and a little boring, I'll not give it more tries if no one beats it. Anyway it's pretty close to the other entry and I still had some fuel left.

Video You have to spawn both of them and be under 250m when you press [ or ].

I didn't looked at the flag until I stopped. But I'll be honest, there is a bug that makes you bounce up after you hit the ground pretty hard, you might even use RCS after that (I didn't). If you gave this challenge a few tries, I'm sure you've seen it at least once. Anyway, I suspect Kevin used it too (EDIT: the bug I mean). EDIT: The main problem with the bug is that you can continue using RCS after hitting the ground (which I didn't), but I'm not sure if it allows you to hit the ground faster then what without the bug would have killed you.

72.0km 9*5'17"N, 59*44'50"E Flag Map