AeroGav

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About AeroGav

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  1. AeroGav

    Impossible Parts Ideas

    The way I'm reading this is practical joke type parts rather than OP ones, stuff that makes you sound like an idiot when you ask for one. Solid Fuel Line (so you can asparagus stage your SRBs) Zero point wings (generate lift from the quantum particles that spawn in the vacuum of space. Don't work in an atmosphere, but allow your space vessel to make banking turns. As a side effect, produces "swoosh" noises and a slight bobbing motion in flight, as if your craft is actually suspended on a piece of string) Space Turbine (very low mass part that produces a continuous engine sound and plume to keep the crew happy while coasting. Occasionally breaks down causing orbit to rapidly decay).
  2. AeroGav

    What did you do in KSP today?

    Reduced frequency of vomiting is worth almost any price. Sign me up.
  3. AeroGav

    Cool Spaceplane ideas

    With Kerbal aerodynamics, it is possible to make a conventional ssto (no lift engines) takeoff and land in its own length, so i've never felt the need to put something like that together. There would be a mass/drag penalty for the lift engines or engine swivelling pivot which i think is greater than that a STOL conventional plane would have. https://kerbalx.com/AeroGav/Puffin After doing this, it flew to Minmus.. And this one landed on the VAB roof helipad, took off again and could have gone to Duna.. https://kerbalx.com/AeroGav/stol Now that said, when there is no atmosphere and gravity is less, VTOL makes sense. I've been watching Season 1 of Space 1999 this week, and I really want to make an Eagle Transporter now, they look like they were based on this real Munar transport concept (though the RL design had bigger propellant tanks and only had the delta V for surface->LLO ops. Eagle Transporters, Barbra Bain, Ziona Morton, this show had so much hotness...
  4. AeroGav

    What did you do in KSP today?

    One thing that really drives me potty about this game is minor updates breaking your craft, mods that add parts just seem to make the picture even worse.
  5. AeroGav

    What did you do in KSP today?

    i didn't mention, but I have a MM patch to add fuel to the wings which gave me the extra range. I also use mod FTMN-80 NERVs which are a little lighter & higher thrust. I could probably drop the radiators, but 1.4.5 it didn't hurt too bad. Nothing else is on the sides, the solar is mounted in the service bay just like you described. I did get around to checking stock parts 1.5.1 vs 1.4.5, in the SPH the dV readout is about the same. I haven't tried a stock test flight in either yet though. The SPH delta V readout only takes account engine ISP and what % of your mass is fuel, put a Wheesly on the first stage if you really want to see some crazy numbers :-) I'd deffo get rid of the rads, i can only think drag losses are what's killing you. If you want lower temps on ascent and re-entry, add wing area, the extra lift means for any given airspeed, you will be at higher altitude so heat will be less. Drag from fuselage parts (which is the major source of drag in stock aero) will be lower for the same reason, so it is easier to fly on a lower TWR. Oh and you have wet wings? More fuel available too. Always chose wet wings over cylindrical tanks where you can (weight and balance, trim issues force your hand sometimes). Dry mass is not such a big deal with 6 tons of NERVs to lug around, a few extra wing parts gets lost in that. It's all about how much fuel you can bring without drag overwhelming your little nerv motors.
  6. AeroGav

    Cool Spaceplane ideas

    For partial re-usable designs, I am a big fan of detachable (jet engine) pods, I've built quite a few that way. The Space Shuttle Way, which your ideas are mostly variants of, I've never produced a satisfactory solution. Aerodynamics is my thing and dealing with off axis thrust/space plane on a stick launches (Centre of lift at the FRONT ?!) is way beyond my vertical launch expertise - the few rockets i build are nice straightforward symmetrical things and even then they mostly crash. Example of a low tech, tier 7 Pather/NERV 2 stage space plane is this - https://kerbalx.com/AeroGav/Kranker Despite having only Panther jet engines and NERV rocket engines, it manages 4000dv in low orbit. The panthers - with their intakes and fuel tanks - are right on the plane's centre of mass so when you punch them off, the airplane doesn't even twitch. Because they don't have to lift or fight the drag of these nacelles any more, then 3 nervs can haul this thing on to space without too much in the way of gravity loss despite the large fuel fraction. If you wanted to kick this up a notch, with more tech available 1. wet wings would make a BIG difference. Lift takes care of not falling down, when your velocity has not yet exceeded orbital (2200 m/s). The problem for these weak and heavy, but fuel efficient NERV engines, is drag. Unlike real life, the vast majority of drag in KSP comes from fuselage parts and cylindrical tanks in particular. Big S wing strakes have a much better capacity to drag ratio than any other tank part. So a wet wing Kranker i'd get rid of all the mk1 tanks i can (except for any i need for trim/balance) and get the rest of the capacity i require by spamming big S wing strakes. 2. Swap the Panthers for Whiplash. Panthers max out at 750 - 800, Whiplash give good power out to 1100-1200. They are heavier (1.8 vs 1.2 ton) but you're dropping them anyway , so who cares. And they are barely any more expensive. Rapiers have an even better top end, but cost 3x a Whiplash, not sure you can justify ditching those in the drink. 3. The main issue is that the airbreathing part of the flight simply doesn't use all that much fuel, so there isn't all that much empty tankage to stage off. You could perhaps replace several some 3 ton NERVs with a single 1 ton Aerospike, and have a bit of LFO tankage on the jet nacelles. This will reduce your dry mass once the empty LFO is gone. The LFO tanks will add a lot of aerodynamic drag, but once they're staged off, you're no longer paying that penalty, and you'll be doing a high percentage of orbital velocity, meaning the wings will not have much gravity left to fight, and will pull you way up into the atmosphere where drag is minimal, and the reduced number of NERVs can finish the job. Hmm, perhaps I should build this Kranker II airplane sometime....
  7. AeroGav

    What did you do in KSP today?

    Nice looking ship, a mixture of some variable geometry fighter bomber and executive jet. I haven't played in a couple of weeks but the 1.5 patch seriously messed with mk2 designs in particular and i also encountered a major issue with how drag is calculated on mk2 cargo bays. It looks like you are using only mk1 parts in this and haven't got any bicouplers on there. so should be good. If you kept to more or less the same fuselage as the example design in the tutorial thread, that ship has about a 30% fuel mass fraction and never could get beyond mid orbit - it simply didn't have all that much fuel - given that Panther engines can only take you to 1/3 of orbital velocity, much of that is used just reaching low orbit. I didn't bother adding more tanks because the goal was to show a simple design that steered the middle ground between running out of fuel before reaching orbit (fuel fraction too low) or being sluggish and hard to fly (fuel fraction too high). It has plenty of fuel to reach low orbit but just falls short - about 100m/s - of being able to do a Munar flyby. So, unless you added extra tanks, i don't see how you'd escape Kerbin SOI on that. I've just noticed there appear to be extra things stuck on the airplane though. Is that an airbrake atop the main fuselage ? Fair enough, it won't add much drag when stowed. However, on top of the nerv nacelles there appear to be radiators? They add a lot of drag, but don't actually cool you down below 70km. I suspect you've now got so much drag it fails to accelerate on the thrust of two nervs (120kn total). What else is stuck on the sides? Bear in mind solar panels add a lot of drag too, the deployable ones are protected from damage by the atmosphere when stowed, but they still make a lot of drag (more than the cockpit, if i recall) which is why i mount them radially on a small battery or reaction wheel in the service bay.
  8. Kerbals sitting on an airliner wing, awesome, reminds me of that film/novel "flight of the Phoenix"
  9. AeroGav

    Build a Submarine That Can Get To Orbit

    OK, I've had some measure of success with this design. https://www.dropbox.com/s/4dqyxyax6ee60qi/Batwing.craft?dl=0 (recently updated with rudder tabs and a slightly recessed nose cone, and some action groups - hopefully dropbox updates the link automatically) First off, going to space, it does easy It can also go under water . It's a bit squirrelly when flying under water, pitch down too much and yaw stability goes to hell. Shortly after this it started tumbling , so i set prograde hold and began climbing vertically to the surface at 35 m/s. Shot out of the water like a submarine launched nuke missile.. which i suppose it is. Plenty of fuel left for the flight to orbit - the first screenshot in this post is from later in the same flight. Actually landing it on the water without busting off the shock cone intake at the front is the hardest part. At first I was stalling into the water at the lowest possible speed, tail touching down first then the nose comes slamming down. I managed an intact landing by coming in more level, about 10 degrees pitch, just under 50 m/s , with a tiny bit of power on. Still this is by far the most marginal aspect of the craft and the hardest part to get right.
  10. Watching Bob push it back made me nervous, I was like "OK Bob, that's far enough, Val's in there!" , was expecting it to fall off the back at any minute.
  11. Stall is just over 40 m/s when full of fuel and ore. I could add more wing to reduce stall, but that might make it too floaty. Your mk2 design wins here because the cockpit has a 45m/s impact tolerance, the shock cone on the front of mine only handles 12m/s iirc. So you'd need floats or hydroplanes to keep it out the water until enough speed been lost. However , while a cockpit at the front of the ship is good for water impact, for the heat of the ascent/re-entry, it's not so great. TBH, one chute might be all you need. Just something to keep the nose pitched up for a half a secod more, by the time it goes into the water drag from the body flopping in has brought the speed down.
  12. OMG ! I've had some success ! Thanks to @Klapaucius for the ore hint. That was something i was missing. I threw this together in a hurry, and it succeeds on two counts : https://www.dropbox.com/s/4dqyxyax6ee60qi/Batwing.craft?dl=0 Sinks... Goes to space Main fuselage stack consists of shock cone, then a diverterless supersonic intake, then the ore tank (full), then inline cockpit, then a rapier. NERVs and Panthers held to wing with NCS adapters. What it cannot do is land in the water without damage. Always busts its nose cone off (unless you use unbreakable joints cheat). Then again, nothing in the challenge rules say it has to land in the water directly. Could use its wheels to land then taxy in for a dip. Launch from underwater is a wild ride... zooms up like a cork and immediately starts flying.
  13. The lift is absolutely negligible, if you press ALT F12 in game, go to Physics, Aero, and check the box "show aero data in action menus" and see how much drag and lift each part is making in flight, you'll be shocked at how badly they compare to wing parts. The hard part of this challenge is the sinking bit. How much ore does your craft carry to make it sink? What is the empty weight?
  14. On a design where you're getting rocket propulsion from chemical propellants, you have high thrust but low isp/limited fuel margins. There is less scope for flight profile to influence the result than with the NERV oxidizer free designs that i make. The main thing is to make sure you're getting maximum speed out of the airplane in airbreathing mode before switching. You should be able to get at least 1300 m/s, even with only a pair of rapiers. Do a level flight speed run at 17-21km for this. Upward velocity is not worth any extra. Once you switch to close cycle mode, remember orbital velocity is about horizontal speed not vertical, so on the one hand you want to keep the plane level and have the engines thrusting at the horizon. On the other hand, you want to get up to higher altitudes where heat and drag are less. However, you also don't want to pitch up too much because that also makes drag. l So, after switching to close cycle mode, i'd say just pitch up gently so the nose is pointing 5 degrees above prograde , 5 degrees is the best angle for lift/drag ratio in supersonic flight. Given that your screenshot shows you above the atmosphere at only 1800 m/s, (in surface mode, that's only 1600m/s true airspeed), you must have either climbed very steeply (and possibly not hit your true air breathing top speed) or you pitched up excessively after switching mode. However you are quite a long way short of orbital velocity so i don't think that would have got to space no matter how flown. 2200 m/s is orbital velocity, if you got 1400 air breathing that means a gain of 800 is needed in close cycle mode, you are only doing 1600, some 200 faster than air breathing velocity. I think you'd be better off with a mk1 inline cockpit design (less drag, less buoyancy). The RAPIER/Panther config i am a fan of, so stick with that. I don't know if a NERV SSTO like mine would work better in this scenario or not. On the plus side, the engines aren't buoyant. Also, since they are damn heavy anyway, the ballast tanks won't hurt delta V so much. But the feeble thrust means you need good lift/drag ratio to continue gaining speed and height after the jets quit. That means skinny mk1 fuselage, lots of big s wing parts (buoyancy!) and requires good control of pitch angle. Every 2 degrees the nose moves away from prograde doubles your drag. On RAPIER close cycle power (180kn per engine) you don't notice it so much, with NERVs (60kn per motor) you will. It would be easier to help if you share a craft file but i'd probably struggle with the "making it sink" part !
  15. AeroGav

    Mountain lake landing challenge

    Far too many buoyant parts, i think the only things on this airplane that sink after a crash are the NERVs - and often they break away from the airplane on a crash landing with the drag reducing nose cone and NCS adapter still attached - in which case those 3 ton slugs of Uranium and Lead defy logic by floating...