Right

At least they give us the jist of the curves. Besides, I currently know of no way to plot multiple hermite splines on top of each other and be able to manipulate the data (zoom, scale, run a lookup at a specific point, divide or multiple one curve by another variable). Sadly, I have to use excel or something like that to do that crap.

If its too easy, try to beat the leaderboard.

Yeah...the Vector is an extremely good engine. Its TWR, ISP ASL & vac, gimbal, and crash tolerance all blow the LV-T30 and LV-T45 out of the water. The Mammoth is the only engine that can match its performance for atmospheric pushing. While the mammoth has slightly better TWR, the vector potentially has like 1/9th the drag while only at 1/4th performance.

So I think you need FAR installed to get underwater speeds over 100 m/s. Which I believe is how WH40krules got 400m/s underwater.

Perhaps I miss understand, but doesn't the route in the OP represent ~2 circumnavigations?

That an interesting problem. Try going into the cfg file of the circular intake and dialing up the intakeSpeed from 15 to maybe 50. Hey Slashy, is occlusion range and centers new?

I think group 4 should be recoverable under its own power - thus recovery through sending up an additional vessel for retrieval would not be acceptable.

Its a suction speed. In ensures that you have some air while stationary. It adds to your current velocity, so its benefit falls off extremely fast once your moving.

Yeah, its more than 4x heavier (.0295 vs .13). We'll probably start seeing more of the stubby aerodynamic nose cone and advanced nose cones thanks to their lower mass. (In rocket booster stages for example)

Air intake scales with air pressure. If air pressure is 1/10th, then air intake is 1/10th. This applies to all intakes. Drag, mass, and cost are all concerns. Shock cones represent a very good optimization of drag and mass but with high cost. Those alternatives which have a better drag (like the tail connector A) tend to have a higher mass. This makes them good for SSTO applications, but often not for rockets. Decreasing thrust does not always indicate a lack of air (in fact, I'm not sure if it ever does). You can spam dozens of intakes and you will still see the thrust decrease at certain speeds and altitudes.

@Paul I've plotted the actual float curve for mach on unity3 and they are smooth in this case...so smoothed curves are more accurate for this. It is the best for raw intake air. Most intakes outperform it at mach 0 though due to its low suction rate though. If I included the Goliath engine's intake on this graph, it would probably do better than everything up to Mach 1.5-ish. @LaytheDragon Thats true. I thought about it but it was going to make my test have problems so I left it out. It will perform just like a normal circular intake just with a larger intake area/more flow. @GoSlash I agree, that will be important to know for single engine set ups. Knowing what produces the most output to drag ratio will give us a good window for starting points. I agree about the shock cone, its going to be overkill when your engines are forced to spool down at high altitudes/speeds.

So intakes are behaving differently. I set up a test rig with all the intakes to map out their performance. Here are my findings: All measurements taken at sea level, 0° AoA +/-0.02°, all intakes simultaneously. We can see four type of curves: 1. Maximum at mach 1.5 (Engine Nacelle, Circular Intake, Small Circular Intake, XM-G50 Radial Air Intake) 2. Maximum at mach 2.5 (Mk1 Diverterless Supersonic Intake) 3. Maximum at mach 3 (Adjustable Ramp Intake, Adjustable Ramp Intake (Radial), Engine-precooler) 4. No maximum (Shock Cone) Next step will be to divide each intake by its drag values to see what has the best performance for the least drag. https://drive.google.com/file/d/0BwgWaXQEa1uwb0lQYV9HSkZTQjA/view?usp=sharing /Discuss

Nice. Loving the new textures too.

Could someone do an example drag calculation for me? I'm close... I can taste it. I've read through the Overhauls for 1.0 thread a few times. Using this example: http://i.imgur.com/DBQUGvH.png Which is a lone FL-T800 Fuel Tank. PART { name = fuelTank_long module = Part author = NovaSilisko mesh = model.mu scale = 0.1 node_stack_top = 0.0, 15, 0.0, 0.0, 1.0, 0.0 node_stack_bottom = 0.0, -15.1, 0.0, 0.0, -1.0, 0.0 node_attach = 5.01, 0.0, 0.0, 1.0, 0.0, 0.0, 1 TechRequired = fuelSystems entryCost = 4800 cost = 800 category = FuelTank subcategory = 0 title = FL-T800 Fuel Tank manufacturer = Jebediah Kerman's Junkyard and Spacecraft Parts Co description = A stretched variant of the FL-T400, the FL-T800 holds twice the fuel in a slightly stronger container. The black stripes along the side make the rocket go faster, our engineers tell us. attachRules = 1,1,1,1,0 mass = 0.5 dragModelType = default maximum_drag = 0.2 minimum_drag = 0.3 angularDrag = 2 crashTolerance = 6 breakingForce = 50 breakingTorque = 50 maxTemp = 2000 // = 2900 bulkheadProfiles = size1, srf RESOURCE { name = LiquidFuel amount = 360 maxAmount = 360 } RESOURCE { name = Oxidizer amount = 440 maxAmount = 440 } } url = Squad/Parts/FuelTank/fuelTankT800/fuelTankT800/fuelTank_long DRAG_CUBE { cube = Default, 4.421483,0.7854716,0.6937256, 4.421483,0.7857229,0.6937256, 1.213026,0.9634836,0.1404351, 1.213026,0.9634838,0.1716429, 4.421483,0.7849605,0.6937259, 4.421483,0.7850149,0.6937259, -1.376047E-16,-0.01320377,-3.882692E-08, 1.25,3.778993,1.250001 DRAG_TIP { key = 0 1 0 0 key = 25 1 0 0 } DRAG_SURFACE { key = 0 0.02 0 0 key = 0.85 0.02 0 0 key = 0.9 0.0152439 -0.07942077 -0.07942077 key = 1.1 0.0025 -0.005279571 -0.001936768 key = 2 0.002083333 -2.314833E-05 -2.314833E-05 key = 5 0.003333333 -0.000180556 -0.000180556 key = 25 0.001428571 -7.14286E-05 0 } DRAG_TAIL { key = 0 1 0 0 key = 0.85 1 0 0 key = 1.1 0.25 -0.02215106 -0.02487721 key = 1.4 0.22 -0.03391732 -0.03391732 key = 5 0.15 -0.001198566 -0.001198566 key = 25 0.14 0 0 } DRAG_MULTIPLIER { key = 0 0.5 0 0 key = 0.85 0.5 0 0 key = 1.1 1.3 0 -0.008100224 key = 2 0.7 -0.1104858 -0.1104858 key = 5 0.6 0 0 key = 10 0.85 0.02198264 0.02198264 key = 14 0.9 0.007694946 0.007694946 key = 25 0.95 0 0 } DRAG_CD { key = 0.05 0.0025 0.15 0.15 key = 0.15 0.0225 0.3 0.3 key = 0.25 0.0625 0.5 0.5 key = 0.35 0.1225 0.7 0.7 key = 0.45 0.2025 0.9 0.9 key = 0.55 0.3025 1.1 1.1 key = 0.65 0.4225 1.3 1.3 key = 0.75 0.5625 1.5 1.5 key = 0.8 0.66 2.3775 2.3775 key = 0.85 0.8 2.733777 2.733777 key = 0.9 0.89 1.1 1.1 key = 1 1 1 1 } So.. Lets assume AoA = 0° Coefficient = 0.9634836 Density = 1.117653 kg/m3 Velocity = 100.025 m/s Area = 1.213026 m2 Running these figures through the drag equation, we get 5.847 kN. However, our reported drag (By AeroGUI) is 5.714 kN. I'm wondering what the game's calculation is, including tail drag, surface drag, and anything else I'm missing. And if anyone is feeling more ambitious, I'd also be curious to see the calculation for this: http://i.imgur.com/blRA6QT.png AoA is 30°, sideslip is 0° Denisty = 1.12298 kg/m3 Velocity = 100 m/s EDIT: Okay its probably a little different in 1.05 now... there is another drag coefficient multiplier - pseudo-Reynolds number. Loving the new descriptions in the Physics.cfg.

I'm happy with one entry per category per person. One cheatery thing I've had success with is using aerodynamically shielded struts in the payload. The rules don't prohibit that, but probably should. I think you summed it up nicely in an earlier post... I see the merit of taking this to the extreme and disqualifying payloads with cockpits, nose cones, or structure... but in reality 90%+ of payloads will have these things, so I think there is also merit to not going that far. (This also leaves room for some fun creativity) Whatever you decide, I'll be happy with, since there are pros and cons to both.

Thats interesting. I haven't looked too much into this yet, but I've seen a variety of opinions on this. Some prefer to go at slower speeds to avoid unnecessary drag. Other seem to operate as if the losses of accelerating to Mach 1.1+ are made up for by being able to ascend steeper and with higher TWR. Not to mention rear drag (Sideflow drag/laminar flow stand in) falls off fast at Mach 1. X axis is Mach, Y Axis is rear drag factor

Wow nice work Val and Nefrums! Would you stop raising the bar so I can get on the airbreathing leaderboard? LOL So the best entries have a TWR of 0.43 on the runway right now, good to know. Sounds pretty creative Johould, its too bad creativity and lag are proportional in this game haha

These reports correspond to wings only. Because they don't include the body, the results don't really recommend any particular methodology during piloting, rather they recommend a methodology for wing inclination placement during construction. Did your AoA drag tests include the body? These figures only recommend high AoAs (30°, first graph) if you're in an emergency. Otherwise, they recommend shallow AoAs for efficiency (2° to 5° depending on speed and altitude). Of course you don't always need the extra lift, but then you're typically better served cutting out a bit of wing and saving the mass and drag. Hmm, wouldn't a decrease in AoA (say from 3° to 1°) decrease your body drag? Also, a refined and efficient ascent profile will deviate from 0° AoA as little as possible (in both amount and frequency). Some planes can deviate as little as 2° throughout their ascent. The idea is that these figures be universally applicable. Thats why the data was sadly limited to just wings (rather than the whole plane, which would be more practical but much more variable).

@RedDwarf I think thats true for most people, and thats the bummer I think. Many suckered into the cool, probably never realize the performance loss. @Jovus Yeah, I mentioned it in the OP. In stock, Mk1 and Mk2 are both 9, and Mk3 is 14% worse. @Kagame True that, can't write off sturdy

Actually, I have to retract my concession about mk2/3 mass efficiency for crew taxiing. Its not very stylish, but its practical.

More efficient is rarely easier, so I'm happy to concede that it may not be easier. Believe it or not, you wouldn't need any RCS, and the mass of the docking ports/fairing is about equal to the cargobay they replace. Yeah I'm all for it! I'd need a baseline. If anyone has a favorite mk3 payloader, I'll try to rebuilt it more efficiently without mk3 parts. Otherwise, I'll do my own later on.

@Obsessed As you probably already guessed, I'm interested in the most efficient and most effective designs. Good points, I'll grant you kerbal storage, and cargo bays for looking cool. But theres nothing about fairings that necessarily hurt your spaceplane's post payload functionality. You just put your payload at the center of the craft with docking ports, and re-dock your plane for re-entry. Not only do you retain you're spaceplane's maneuverability, but you've reduced its drag profile, which can't happen with cargobays. Mk3 fuel tanks did have the best ratio once upon a time, but they are among the worst now. @GoSlash The Mk.2 cockpit has a great Cd, but it comes at a huge cost. First and foremost, it has twice the area, which causes it to fall behind the Mk1 even if we're talking 0 AoA (0.344 vs 0.506 thanks to a handy PM!). As soon as you start pitching up or down, Mk2 starts to really get bad. Second, it comes at a high mass expenditure. Longer sections don't increase its drag? In other words, a single Mk3 Long Fuselage has the same X & Z drag as a stack of 2 of them do? Edit: Oh are you talking about sideflow drag?

Not sure I follow. I make them all the time, they look fine, no clipping. There are twice as many 1.25 crewed pods than Mk2. You have fairings that can often do the job cargo bays can. Heating isn't a matter of length of time in atmo (E.g.; doesn't add up past 1-2 seconds), but speed and air density. Besides, only the leading part is exposed to significant heat, which is typically a high max temp nose cone or intake. Even if not, I've used the FAT wings on spaceplanes (40% less max temp than a regular tank) without too much trouble. Engines have nothing to do with it, there are no mk2/3 configured engines (which is actually yet another disadvantage). In terms of aero losses, its more than a small difference.

So I am having a hard time seeing the point to Mk2 & Mk3 parts. Heres a breakdown. Mk2 parts compared to size 1 AKA 1.25m parts, Mk3 parts compared to size 3 AKA 3.75m parts. Mk2 Disadvantages: The lift from Mk2 body parts is offset by mass proportional to any fixed wing - not a disadvantage technically, just a wash. The Z+/Z- area is twice as bad as a size 1 equivalent part. To make matters worse, its Z+/Z- drag coefficient is horrible. This causes much more parasitic drag (not the good kind) when pitching. One test I did showed twice the drag at only 5 degrees AoA! The Y+/Y- area is twice as bad, and is harder to fully occlude with low mass, low drag-coefficient alternatives. Mk2 Advantages: The X+/X- area is a little worse, but its drag coefficient is pretty decent so makes up for it. But personally, my spaceplanes rarely need to yaw, so this advantage is lost on me. These parts have a higher crash tolerance, overall more sturdy. 25% better max temperature. Mk3 Disadvantages: Both the Z+/Z- and the X+/X- area is almost twice as bad (for an equivalent mass of fuel), On top of this, the drag coefficients are worse. Both pitching and yawing cause considerably more drag than a size 3. The Y+/Y- area is, again, harder to fully occlude with low mass, low drag-coefficient alternatives. Dry mass per fuel point is 14% higher. Mk3 Advantages: Y+/Y- area is like 8% smaller, if the stack remains Mk3 throughout the stack (which I don't often see). Higher crash tolerance 35% better max temperature So, considering how much time spaceplanes spend in the atmosphere, it seems like the aerodynamic penalties are pretty damning. I can't help but feel like its backwards... rockets blunder straight up through the atmosphere with high TWR while spaceplanes carefully navigate through it, shouldn't spaceplane parts be more aerodynamic and rocket parts be sturdier?

So I made some detailed experimental ones for lift. http://forum.kerbalspaceprogram.com/threads/138291-Wing-Lift-Wing-Lift-to-Drag-Ratio-Charts?p=2274518#post2274518 I might do mach later if anyone is interested.