AeroGav

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About AeroGav

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  1. Get friend zoned by Soolin. Then try my luck with Jenna. If Cally looses that 80s poodle perm, maybe I'll even creep around her for a bit. Then teleport over to the next Liberator ship and see how it goes with the clones of the above crew members. Repeat 9999 times.
  2. The tank i used in my screenshot above was in the middle of a stack, it had the shock cone at the front and a cockpit behind it. You could reduce the drag of the tank by mounting the wings at 5 degrees incidence angle and flying the fuselage on prograde, but that's not a fair comparison as you wont fly on prograde hold for much of the airbreathing part of the flight, you'll probably be at some negative fuselage aoa. More wings = less drag during the nerv part of the flight, less wings = less drag & faster acceleration on airbreathers since nervs are so heavy and underpowered, the main driver of my designs is how it flies in the hypersonic part of the flight. Getting through mach 1 is the next most important part, and you can improve this by fitting less wings than i normally do, but i don't like to do that because it makes the nerv part so much worse. You can still easily break mach 1 even with a flying wing design. That said, my designs are criticised for taking a long time to reach 1500 m/s in the speedrun, with less wings and drag, and flying lower where there is more intake air and thrust, i imagine your ssto can get to 1500 quickly, even on a single jet engine.
  3. ??? 0.44 drag on a big S strake, lift rating of 1 Last time i checked, all wing parts have same lift to drag ratio, so a pair of big S wings (lift rating 10 for the pair ) would be 4.40 kn drag at the speed , altitude and angle of attack in that screenshot. Equivalent to 3.18 mk1 tanks, not 7. Given how heavy NERVs are, I'm inclined to make all my fuel tanks Big S parts to make this part of the ascent easier (get out of the lower atmosphere faster, once you pitch up from the speed run). This does slow down the air breathing part of the climb, when you can't just fly higher because your engines need air to breathe. On the other hand it makes landing speeds so slow you're guaranteed to survive no matter where where you land and enables some of the dumb stunts i've done (mountain lake to minmus challenge on the Puffin, or takeoff/land from the VAB roof while fully fuelled)
  4. Don't trust the red arrows, they are not to scale. Use ALT+f12 > physics > aerodynamics and tick the "show aero data in action menus" checkbox. I did a quick test - Those strakes on the back of the main wing have 0.44 drag, if you used 4 of them to have same capacity as the fuselage tank , you'd get 1.76 drag, which is slightly higher than the mk1 tank. To an extent, you can compensate for this by busting mach 1 at a higher altitude, since the larger wings enable you to fly at low angle of attack in thinner air, but beyond a certain point thinner air makes engine thrust fall away faster than drag, so yes, you get better airbreathing performance with small wings. However, when you are on NERV power, the lift from the larger wings quickly takes you up in to the thinner air above 30km, where fuselage drag and heat are greatly reduced. I find myself applying nose down input at 20km for the speedrun but once i've lit the nukes and pitch for optimum lift/drag, it zooms upstairs , levels off and starts to gain speed quickly.
  5. No, mk2 has about 2 and a half to three times of a mk1 part of the same length. This is terrible for fuel tanks as they contain no more fuel than a mk1 part of the same length. For passengers, they are not so bad as you get twice as many kerbals per module, but the kerbals to drag ratio is still worse, especially given that you'll now need mk2 to mk1 adapters at front and back of stack, which contain oxidizer tanks you are not using.
  6. probably because of the wing incidence angle allows flying on prograde lock, so the engine parts and the empty nodes are now at zero angle of attack, reducing their drag, allowing you to get away with not having them. I'd still keep them personally, it's not like you're going to notice the dry mass reduction with the weight of all those nervs on such a vessel
  7. Intakes don't work properly if facing backwards in fact - as you get faster, they normally bring in more air, but facing the wrong way, they intake less which is bad news as that's just when engine demand starts to go up. I do normally still put cones on the back of all my engines because busting mach 1 is the hardest part, the less jet engines you need for that, the more delta v or payload fraction you can bring as those things are heavy. However, the difference in drag between aerodynamic nose cone vs shock cone are very small compared with the drag the mk3 fuselage parts are creating. This is the area you should focus on in my opinion. Ways to get the fuselage drag down 1. add incidence to the lifting surfaces, as IronMaiden has done, so the craft will fly on prograde. 5 degrees is optimal angle of attack for lifting surfaces at supersonic/hypersonic speed - which coincidentally is what happens when you hold SHIFT-S during part attachment. 2. try not to use any fuselage fuel tanks. Seriously , liquid fuellers don't need them. If you swap all your wing parts over for big S ones (including your vertical stabilizer), you probably have enough capacity to get to orbit without them. Check out my Andromeda freighter, which can put an Orange tank in orbit. https://kerbalx.com/AeroGav/Andromeda In practice, you will probably still need some kind of fuselage "trim tank" to get the CoM where you want it to be, or to make sure it doesn't shift around as the fuel burns off. But , it might not need to be a full mk3 one. Maybe just a mk1 lf tank up front, behind the intake cone? 3. That mk3 "Space Shuttle" engine mounting plate can be very draggy if you don't use it right. Your craft notes say it was based off my "Lusitania" ship.. hopefully you copied the attachment method that thing used ? Remember folks, it has a center 2.5m part attachment node in the middle of the three "vector engine" mounts, and you get an eye watering flat plate drag penalty if you don't put something on this. I usually fit a 2.5m tri-adapter on there, for three more mk1 sized engines. I clip that adapter inside so it looks less like the airplane is suffering a prolapse, then offset the engines horizontally so it looks like they are attached to the sides of the rear fuselage. I can't download your ship as I don't have "making history" x-pac. Two other changes i'd probably make if it were mine - i'd swap half the rapier for panther, this arrangement gives slightly more thrust for busting mach 1, weighs 2 tons less, at the cost of a negligible decrease in top speed in level flight, airbreathing mode. There's not much in it though. I'd probably want some other cockpit arrangement, for "quality of life" if nothing else. That mk3 cockpit gets so hot as it is at the front. The nose cones etc on its front node don't shield much of it from heating as they are much smaller diameter part. You could fit some kind of mk1 or mk2 inline cockpit, via a series of mk3 to whatever size adapters (would do double duty as your trim tank). Or put a mk1 inline cockpit at the front of the cargo bay, and offset it upwards so only the bubble canopy pokes out the top. That way you can still fly it from the in cockpit view, but the cockpit is still shielded from the drag and heat. This is the method i used in "Monstrosity 225L"
  8. Also, the air mattress has a plastic skin. Plastic is made of carbon and hydrogen, both of which are very rare on the moon.
  9. I've often wondered what a lunar habitat might be like if it started growing itself with in situ harvested resources. Lunar soil and rock appears to consist mostly of metal oxides and silicates. So, probably one of the very first things a colony with aspirations of becoming self supporting can do, is start excavating additional habitable volume for itself, and constructing bricks and furniture items out of carved stone. In 16% gravity, they would not be particularly bothersome to handle. In terms of processed/man made materials, smelting the regolith to separate the metals from oxygen (which is also useful..) is centuries old tech. However, the moon appears to have very little in the way of lighter elements such as carbon, hydrogen or nitrogen, these only being found in ice deposits in permanently shaded craters. On such a base then, everything possible would be constructed of stone, metal , glass or porcelain, these being relatively cheap due to the materials being locally available. On the other hand, plastics, wood, and textiles, the cheapest available materials on Earth, would be luxury items on the moon, having to be imported at great expense. So your bed frame would be stone or metal. The mattress would be sprung, and the pillows stuffed with wire wool rather than foam or feathers. Only the outermost cover would be textile. Perhaps only wealthy colonists would use sheets or duvets. Your living room might be quite spacious, carved into a cliff face, with quite generous glass windows looking out over the moonscape. Again, if you're wealthy, you'll have an armchair with a textile outer cover.. otherwise make do with stone or metal. A kiln probably isn't difficult, so expect to have plenty of porcelain dining ware. The real big ticket luxury item is however your entertainment system. A PC can do the job of games console, tv, radio, and workstation, and the bulkiest , heaviest components like the case and heatsinks, cooling fans, could be made locally. PCBs are medium tech and can be refurbished on site with surprisingly modest equipment in case of most failures, but actual manufacture of the PCBs is harder, and the integrated circuits they contain would have to come from earth. Fortunately they are tiny and light. It is still likely that new motherboards/graphics cards would ship from Earth. PCs have an advantage in being modular, but perhaps small form factor (Mini ITX ?) would save shipping cost. All of this pales by comparison with whatever you've got to use for the display however. There seems no way around this - large LCD panels are hard to manufacture yet are also heavy, fragile and bulky. Your monitor or TV is probably worth more than the rest of your apartment put together !
  10. OPT parts have horrible drag, worse than mk2. I think the authors of the mod calculated drag based on volume of the fuselage section, so as they have more internal volume than mk2 drag is scaled up accordingly. This seems to be how squad calculated drag on the stock parts - mk2 parts have more volume than mk1, so they gave them more drag. Except that in real life, that wing body blending reduces drag at transonic/supersonic speed (at the cost of higher weight), and in real life, the wing/body blending can be used to store a lot of extra fuel, whereas in game, mk2 parts contain no more fuel than mk1 of the same length. There is a wonderful mod called Kerbal Wind Tunnel that will tell you if your design can break the sound barrier without even leaving the SPH. It also shows top speed at each altitude, so you can work out the optimal altitude to attempt to get supersonic at.
  11. I'd say its all about lift drag ratio. You want to get the best exchange rate possible, that means maintain the nose 5 degrees above wherever the prograde marker is pointing. When you deviate a couple of degrees off this 5 degree angle of attack your lift to drag ratio goes to hell. Looks like you're able to make this work by getting into a 30 degree zoom climb after reaching 1200m/s at 10km when the Whiplash is still making a lot of power - by the time your upward momentum has run out, you've gained enough horizontal orbital velocity. My designs are intended for a level flight speedrun at 17km, then start the nukes, and once the jet power is dying away about 1350 or so, ease the nose up so it's 5 degrees above prograde and keep it there. If your lift drag ratio is good enough it should work. To do that in the above craft i'd want 3 times the wing area and switch to an inline mk1 cockpit. Pointy cockpits get much hotter, and with smaller wings relative to your weight, your craft goes lower in the atmosphere for any given speed when means more friction heating.
  12. This craft of mine was built for the mountain lake landing challenge. https://kerbalx.com/AeroGav/Puffin Seaplanes are tricky, change one thing and there is no guarantee the craft will lift off the water again. It can comfortably land on Minmus starting from a standing start on Kerbin, and i used the cheat menu to put in orbit of Laythe and verify that after de-orbit burn, it can land on and take off from the ocean with nearly full tanks, and then fly to Laythe orbit with 2500 dV left once in orbit. So if you'd rather not mod this airplane, build something with a Claw that can refuel it in Kerbin orbit, for the trip to Jool, and then put another low grav IRSU lander in jool system to gas up for the return leg... the irsu lander could touchdown on a low grav world like pol or bop. The IRSU lander can be tiny because this thing doesn't take much gas. Something like 10T of liquid fuel to completely fill it. Doesn't use oxidizer, except for the ventral vernier thruster.
  13. I ended up overshooting and climbing too high on my initial burn, reaching an AP of 65km at 1900 m/s - this thing makes a lot of lift ! So i cut the engines and let it coast down on prograde. Restarted engines at 50km, things start getting hot below 40km, end up pulling several Gs from lift at 37km to level off. Overheat bars are shrinking again so i start pitching down, trying to delay my broaching 50km as long as i could. If going above 70km before the record attempt is against the spirit of the challenge, i feel like i could use some high thrust LFO engine for the final fling, when its no longer possible to stop the ship climbing and you just want to get as much velocity as you can before you bust 50k
  14. I don't have time tonight to design anything specifically for the challenge, but I wanted to see what a recent airplane of mine would do. I give you the Korten Fledermaus flying wing - https://kerbalx.com/AeroGav/korten-fledermaus Still had plenty of fuel left but those Type B nose cones like to melt. They are fairly important, they keep the NERVs attached to the wing. Doesn't accelerate much once these pop.