AeroGav

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About AeroGav

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  1. Closest I ever got to an interplanetary "space shuttle lookalike" was this https://kerbalx.com/AeroGav/Columbia-IV, since I clipped Xenons into the Terriers and Sparks to make the exhaust plumes blue. It would still need refuelling to get to Laythe though, and wouldn't take off again. This would serve you much better though, https://kerbalx.com/AeroGav/SSTL-gavd Over 4k delta V once in orbit, and it has mining equipment
  2. Science labs do require a lot of power, a continuous draw while processing data (which it will be constant in career mode) with heavy bursts when transmitting the processed stuff back to Kerbin. So all those batteries scattered around will help with that. The probe cores are pretty light compared with the lab and hab modules they attach to, and provide a bit of reaction wheel torque for the station. All those docking adapters are an overhead compared with doing fewer, larger launches but of course there are limits to how much you can easily launch in one go. Most of my spacecraft don't have a full rcs system (since most are spaceplanes/tech not researched in career mode) and can't translate up/down/left right, they just have a main engine and reaction wheels. So to dock, i bring the two vessels close together, set the other vessel's docking port as target, point myself at it with RW, then switch to the other vessel and do the same. Then i just use a tiny nudge from the main engine to go forward, and the two things will meet nose to nose.
  3. One thing that may be hindering us is that the Vector is actually nothing like the real RS-25 (SSME). It is much heavier and more powerful than the real shuttle engine ; the real shuttle actually had 80% of takeoff thrust from the SRB. I did try building a stock shuttle with 3 swivels on the orbiter (if you offset them forward so only the bell protrudes from the mk3 engine mount, they look a lot more like shuttle engines) and 2 kickback SRBs. This gave us a CG that was further forward and it would have been aerodynamically stable during re-entry and landing. Unfortunately it would still have taken a lot of work to make it fly properly on the way up and I couldn't be bothered to stay on it. On liftoff, CoM is well below the Orbiter, over time this moves upwards as the tank and SRBs get lighter, which increases the pitch up moment from the SRB thrust as their distance from CoM increases. At the same time, CoM is moving aft as the tank empties, which reduces the aerodynamic ability to fight the pitch up, as does increasing altitude. In my sig. is a link to my KerbalX craft - I've a few "nearly shuttles" in there, they all have four SRBs mounted symmetrically around the Orbiter and internal fuel instead of ET, and have much lighter main engines than the Vector - these are much easier to design and fly, if you're willing to stomach the compromise. (smaller cargo bay as a result of the internal fuel)
  4. for 400km an airplane would be better, but i won't accept these contracts at all if they require me to fly beyond my own continent - not time efficient. An engineer kerbal can mend broken wheels, but the basic one is very fragile. Hardest thing is not having them tip over, getting CG low enough usually means abandoning cockpits for structural panels and command chairs. I had some success with one built like a Tesla, with batteries and RTGs under the floor but protected by a metal plate (keeps cg low). Still had to turn wheel friction down to guarantee not tipping over. Also, reaction wheels should be fitted but set to SAS only - that way they try to keep the craft upright, but wont try to torque it onto its nose when you accelerate forwards. They can be put back in normal mode when you do tip over and need torque to roll it upright. Lastly, giving it a "sloping roof" like a house, stops it settling on its roof (makes it easier to right again) and protects the kerbals in the event certainty of a rollover accident.
  5. Current plan - mother ship lands on Laythe. The drill of the lander angles down at 45 degrees and will poke through floor of cargo bay to mine the soil if i retract the airplane's gear. Then hop out to Val, shed airbreathers. Mother ship can probably also land here in the low grav. For tylo, detach the 2.5m lander, it goes down alone. Margins are tightest on this part. Refuel on surface. Jettison irsu gear, burn back to orbit, shed propulsion stage, re-dock with mothership using rcs. Then mothership lands on bop and pol before heading back to Kerbin.
  6. It still has 2 way symmetry. Whiplash top left and bottom right, rapier top right and bottom left, or was it the other way round? The cargo bay must actually be pressurised. It's just Val's got some really strange ideas about hygiene or the bay is pressurised but not man-rated, the Kerbals have to stay suited in case of explosive decompression More to the point, Jeb's going to be very disappointed when he picks up a slice of that pizza. I'll play this some more on monday, atm i am in the jool system with 1100dv and can't figure out all the gravity assists. I either get shot out past Eeloo or end up on a terminal plunge into the depths of Jool, to be crushed by the intense pressure.
  7. One more thing - the OP has met his aims, but it's worth talking about the Breguet Range Equation for aircraft - depends on % of takeoff weight as fuel, lift:drag ratio and engine efficiency (ISP). Lift:Drag ratio is highest subsonic, i've seen over 10 to 1 at 120 m/s, falling to 6:1 at 240. Then it really takes a dive. Between 0.9 and 1.2 mach, you'll have a hard time getting even 2:1. Then it recovers somewhat, basically from mach 1.3 up to orbital speed, l/d ratios are about the same , and i've managed 4.3:1 with some aircraft. So, if time is no object, go subsonic. Avoid transonic like the plague, but most likely we're talking about a mach 1.3+ design. If you're happy with less than mach 2, you can make something that runs on panthers in non-afterburner mode, with 9000 ISP these supercruising designs can be very economic. However, Panther (dry) thrust falls off a clifff above mach 1.9. And if you want to go faster than that, there's not much difference in the engines (afterburning panther - 4500isp, whiplash 4000, rapier 3200). Bearing in mind that l/d ratios are about the same at mach 1.5 vs mach 6, there is no reason to go slow. In fact, a new factor starts to take over above mach 4, which makes things more economical the faster you go. >>Orbital freefall. Above mach 4, orbital freefall effect supports an increasing proportion of your plane's weight, so you need less lift. Given the same lift:drag ratio, that means lower drag is possible. To realisise this theoretical advantage, you of course have to be holding nose at 5 degrees above prograde, and be at very high altitude. Somewhere between 22km and flameout height (the higher the better). TLDR - build a mach 1.6, 15km supercruiser using dry panthers - if that's not fast enough, then build a rapier bird to fly at mach 5.5 at 25km.
  8. Something else you need to do for minimum drag is put cones on the back of any engines that have rear attach nodes, because all empty attach nodes have high drag. For example, if you got whiplash or panther engines on the 1.25m nodes, they are low drag. But if you are using rapier or terrier, any kind of stackable engine, you need to put a 1.25m nose cone on it , then offset that cone forwards so it doesn't block the exhaust. The Poodle has a 2.5m node on the back of it so is even more draggy unless coned. Also - the cones have to be the same size as the node they are covering or most of the benefit is lost. As for stability/control - it should be possible to have both. You'd need to give us pictures or a craft file to diagnose that however.
  9. To have low drag with that engine mount you need to have all 3 1.25 m nodes occupied and the centre 2.5m one. If no engine on one of the nodes, it needs to have a cone of the same diameter as the attach node instead. if you're putting a 1.25m engine on the centre mount, then you need a 2.5 to 1.25 adapter drag might provide some stability but lift is much better. Horizontal and vertical stabilizer area at the back, =win
  10. It's a self launching spaceplane that takes off from the runway.. it takes off with a whiplash engine that is jettisoned at flameout height, then uses the lv-n after that. Not really for career though - the big S wings it uses are 1000 tech cost parts deep in the aviation tree Surprisd about your duna mission struggling. You do realise the lvn doesn't use oxidizer, so an orange tank to fuel it would be carrying loads of useless oxidizer? Also did you use a launch window planner to get a good launch date? I used to just eyeball it and would end up using 2 or 3 times as much delta v
  11. https://www.dropbox.com/s/8mqztewnygsh6em/alleged tylo-laythe assist.sfs?dl=0 you'll have to install Kerbal Furniture mod though, because the craft has a "lounge" area :-/ Beware i might have turned some of the engines off or limited thrust at this point to fine tune the manuvers, can't remember exactly
  12. You can "limit authority" on the item used as a flap so that when "deployed" the total of it's angle and the wing it attaches to + airplane body aoa does not exceed 30 degrees. You can put flaps ahead of cg to balance the ones behind and get around trim problems , eg. put some on the canards as well as main wing. Note that flaps put on the leading edge of the wing can't hinge down like real life slats - they have to deploy upwards if you want them making lift! Which brings us onto the main problem - they don't work like real flaps do, which are only a small percent of total wing area, but increase lift across the whole wing by increasing the apparent curvature. In KSP the act of deflecting only affects the lift produced by the flap itself, so the overall effect on landing speed is not worth the trouble. What might be better - on a Duna airplane, with v large wings, you have the problem of making too much lift during the speedrun at 22km. Lowering the nose to suppress this, if the wings have incidence, creates negative body aoa and high drag. Some kind of spoiler might help here? But, what happens when the main wing stalls and creates retro torque on a tailed design? The main wing is ahead of cg, not by as much as a canard, but it is larger. The test i did, with two otherwise identical planes on re-entry,, with same relative cg + col, the canard and tailplane were able to hold the nose up radial out to the exact same altitude before aero forces forced them unstalled. These were both very stable aircaft, not able to pitch much more than 10 aoa however. You can try out my little "ghoul" jet , it is so small, the cockpit reaction wheels can force the nose to 45 degrees aoa at low speed. The main wing is at 5 degree incidence so will be stalled by 25. https://kerbalx.com/AeroGav/Ghoul
  13. My tip - start with an inline cockpit and some crew cabins, then put engine nacelles either side of the crew area. Now add fuel tanks ahead of and behind the crewed bits. That way you got fuel tanks ahead of the cockpit, to absorb heat (and any landing crashes). One engine at the back forces you to put the crew areas up front to balance the empty mass of the ship (with fuel going in the middle), and the cockpit gets heated. If you put crew in the middle and engine at the back, with fuel up front, then the plane becomes tail heavy and unstable as fuel burns off.
  14. Yeah my Galaxian has engines well forward , especially the heavy nukes. Rather a homely bird though (the SSTO, not Val). Doesn't help that i keep sticking strakes on to balance CoL, but hey it makes loads of lift and has lots of LF for interplanetary stuff. Why do you need a rover again when you've got a plane? Well, I suppose they're fun. And the plane can come and collect the Kerbals after you crash it.
  15. Since we're talking ramp birds, i built one not so long ago in case i ever needed to put a rover on another world. https://kerbalx.com/AeroGav/C7-Galaxian From the front in particular it looks like it's been glued together from scraps and offcuts, but it does actually fly pretty nicely, and packs a serious amount of interplanetary dV. @Rune Oh yeah, going back to our earlier discussion, my min-maxed designs do in fact use a 1:1 ratio of rapiers to nervs and 200-300m/s worth of oxidizer. It was more about the dilemmas of building a smaller 3 engine craft, when you're forced to choose which engine to have two of and which for one. I was just building 2 nuke ships to show that they work better than people think (common wisdom seems to be they'd be really hard to fly or not fly at all). Also if you got 2 nukes in something well streamlined under 30 tons, oxidizer is a waste because you already got plenty closed cycle mode power. This week I also built my largest spaceplane ever - 183 tons (not by some folks standards, but big for me). https://kerbalx.com/AeroGav/Liv-Tylo I'm currently testing it with a Jool 5 mission. The fuselage is entirely cargo bay and features IRSU, a 7 seat tylo lander, a 6 seat rover, and a recreation area (kerbal furniture mod). It's not fully SSTO, in that it has a drop tank and two whiplash boosters. Main propulsion is a panther, two rapier and four nervs.