ChevronTango

My protip is to get as much lift out of the wings as you can, by tilting them back to 25 degrees to horizontal (the optimal angle of attack in Kerbal... for now). It means the wings are more efficient, you can keep the plane pointing horizontal and not waste fuel by having the jet engines firing nicely prograde. Less wings means less drag too.

I've been studying this further. I did a quick experiment with a single rocket launched straight up, then again but with as many small landing gears strapped to it as I could get on it, both deployed and stowed, and each time I reached a max height of exactly 2353m. Draw your own conclusions about mass and drag.

So I'm hoping someone else can shed more light on this than I have done so far. Near as I can tell their are two classes within Kerbal that implement the Landing Gear Behaviour, "LandingGear" and "ModuleLandingGear", the latter of which is the one employed by the gear in question. From what little I can read into it, the "LandingGear" sets the drag values I stated before and implements them correctly, ie updating the values based on wether their stowed or deployed. It does this in the onPartFixedUpdate() method, and without testing it I can't be sure, but I'm fairly certain the behaviour is correct. The ModuleLandingGear, which is relevant as its the one we are actually using, does not assign any values to the stowed and deployed drag properties of the class object by default, and looking through the part.cfg for landing gear, can't see an ovveride, so my assumption is these are left as null, and thus the debate on wether drag comes into this in any way arises. ModuleLandingGear does in fact update the drag values with the relevant ones in its Update() method, but I don't know for certain if that method is Ever called, and even if it were, with null's representing those variables no doubt headache's would ensue. In Summary, I looked behind the curtain, and I'm amazed Kerbal works at all sometimes. if your feeling daring try updating the landing gear's module to what I think is the correct one (LandingGear) and see if that makes a difference. I didn't see anything wrong with the mass, I'm assuming that's all inherited nicely, but I'll need to look into that further and get back to you all to be absolutely sure. Edit: To Clarrify LandingGear extends the Part class directly, whilst ModuleLandingGear extends partModule, so you can't really swap them like I suggested, and they both have no relation to each other, other than being similarly named.

I made a complete fool out of myself with this one. The drag of the landing gear jumps from 0.1 to 0.7 when comparing stowed to deployed.

Having looked through the equations, there is no difference in drag in the slightest, its a fixed constant. Raising or lowering the gear does nothing to the flight in any way, so knowing this I always leave them down unless I'm taking photos. The change in gear only starts the animation.

I don't know of a way of holding your heading like that when in orbit, however for ease of docking, I always align my space station north-south when its on an equitorial orbit. That way I always know when trying to dock with it, that I should approach from south to north, though I'll need to rotate my alignment when I get nearer. The space station will continue rotate the way you described, but around the north south axis, so you might as well keep it pointing that way for ease of docking.

Near as I can make out, the wing area doesn't play a part in any way, only the lift value. The lift value is not calculated, its set by the part in its settings, so no doubt the Kerbal designers put in a higher lift value for larger parts. My advice for high lift to drag and weight ratios is to use delta wings. Angle them back 10 degrees and don't use two many, though for duna or some other atmosphere you'll probably want more. Some quick calculations of the equations suggests that the ideal angle of attack is 25.7381 degrees. As in that generates the maximum amount of lift for the velocity input.

DeflectionLiftCoeff is the lift value of the wing specified in the VAB and in the cfg file, yes. I'm aware of the differences between the up and forward vectors, the one's I've stated up there are the sensible interpretations of forward and up for a wing. (Forward is parrallel to the vector to the planets core when on the runway, not necissarily away from it. With the symmetry in the SPH, one wings' forward will be up and one will be down due to rotation, not reflection.) The only thing that changes when a control surface is adjusted is the velocity vector that's fed into that lift equation, though I'm still trying to work out the exact tranformations used to adjust it. I imagine if that can be fixed to be more sensible, we may see the infiniglide bug dissapear. It should be noted that the position on which lift acts on wings and control surfaces are different. With Wings and static lift surfaces the lift is aplied to the joint between the wing and the object its attached to, whilst with control surfaces the lift is applied to the center of the objects surface (read center of mass). The plugin I wrote demonstrates this.

You can cruise at about 28k easily with a few more intakes than you'd expect. The issue with ASAS is that it doesn't take into account curvature of kerbin, so after a while you may find your nose pitching up, as it tries to keep its heading. I only ever really notice this on atmospheric circumnavigations though.

My Pro Tip is to angle the wings back by about 10-20 degree's using shift+[WASD]. If the wings are parrallel to the ground occasionally angles and things conspire against you and you can end up creating lift into the runway (rather counter intuitively). Angling them back ensures you are generating the lift up, and means at higher altitude you don't have to point your nose up as high (and therefore not waste as much fuel with engines that you'd ideally like pointing prograde)

So after some research and digging in the kerbal source binaries, as well as some experimenting with plugins and custom lift equations, along with debugging the forces by drawing in the vectors, I've actually managed to translate the nonsense lift equation kerbal uses into plain english. CrossProduct(velocity, wingRight) * Cos(StupidAoA) * (1 - Abs(Cos(StupidAoA))) * Cos(AoA) * deflectionLiftCoeff * StaticAirPressure; where AoA is the angle between the velocity and the forward vector of the wing, and StupidAoA is the angle between the velocity and the upward vector of the wing, wingRight is the vector to the right of the wing as placed, or can be thought of as the cross product of the wings up and forward vectors The practical upshot of this I've found, noticeable when debugging in particular, is when rolling down the runway, quite often I'm producing a massive force downwards into the runway, explaining why I can't take off until I fall off the end of the runway and my angle of attack suddenly changes enough to snap my lift back upwards and I can take off. The Control surfaces use exactly the same equation, but the velocity fed in is transformed first to adjust the result of the lift equation. I can understand why that's done, and I'll try and post the simple english of that specific transformation in the coming days, but it shouldn't be too hard to guess that. I'm attaching some debug Plugins I've been using, if you change any control surface or winglet's module from "Winglet" or "ControlSurface" to "WingletDebug" or "ControlSurfaceDebug" respectively in their relevant part.cfg you should see the debug lines for lift and velocity drawn. http://www./download/3ad8dn5rrk71h78/KSPLiftMarker.dll

I didn't say she was a sensible/realistic design. She's just a space sculpture.

Quick Update, I'm now up to a staggering 1470 parts with the two new hangar/engine modules, replacing the one's with the engines backwards. Its quite a large amount of generators to power those engines, just adding to the rediculous nature of the whole venture. I know this is silly, you know this is silly, but its good fun regardless.

1066, 5 sections which are the main center, the front, the two sides, and the lookout on top. i'll be redoing the two side sections, with way more generators, a proper covering to the front to hide them, and the engines the right way round. Wasn't until it was in orbit that I noticed, but since its never going to leave orbit its a moot point now.

So I present the KSS Othello, based off the Daedelus off of the Stargate franchise. This is my first big design, having not logged many hours in kerbal yet. I have only successfully landed on the mun once but I found a bit of a passion for space building and docking. She's entirely decorative, though her two poodle engines are fueled and ready for use should the time come, as are the Ion Engines, but I doubt they'd do anything to be honest. She's entirely stock except for a few mechjeb's which I forgot to take off, so I'm hoping you purests can forgive me that. I only used it for the rendevous, the docking was all manual. She weighs 253 Tons and has a massive 1066 parts, and was assembled from 5 sections. Almost everything is for aestheitcs, I'm well aware things like the jet engines serve no practical purpose, but I was working off rule of cool. She was never going to break orbit anyway. Let me know what you guys think.

So I present the KSS Othello, based off the Daedelus off of the Stargate franchise. This is my first big design, having not logged many hours in kerbal yet. I have only successfully landed on the mun once but I found a bit of a passion for space building and docking. She's entirely decorative, though her two poodle engines are fueled and ready for use should the time come, as are the Ion Engines, but I doubt they'd do anything to be honest. She's entirely stock except for a few mechjeb's which I forgot to take off, so I'm hoping you purests can forgive me that. I only used it for the rendevous, the docking was all manual. She weighs 253 Tons and has a massive 1066 parts, and was assembled from 5 sections. Almost everything is for aestheitcs, I'm well aware things like the jet engines serve no practical purpose, but I was working off rule of cool. She was never going to break orbit anyway. Let me know what you guys think.

So I just finished building this and thought I'd share. No idea if anyone's built similar on here already, but taking my inspiration from the Daedelus on Stargate SG1 and Atlantis, I present the KSS Othello. She is entirely decorative, though she's fueld up, and has enough generators to fire all the ion engines, though not sure if they'd do any good. She weighs 253 Tons and has a staggering 1066 peices. I wasn't going for efficiency, I was going for aesthetics. Anyway, let me know what you guys think. My PC can barely cope with looking at her, so Lord knows how I ever got the last peice of 5 attached.