Wanderfound Posted March 8, 2017 Share Posted March 8, 2017 Kerbotruck (AKA "you don't need that much wing") Takes off with no fuss and room to spare: Easy through transsonic in a 10 degree climb: Tough enough to cope with a low altitude zoom-climb ascent: Keep the jets breathing until their altitude ceiling: Fully fueled to a 150km orbit: Superb heat tolerance permits an aggressive reentry: Tough airframe allows you to wash off speed with G's: Very stable and controllable at low speed: Easy lander: Craft file at https://www.dropbox.com/s/pfq60n0yfspeihe/Kerbotruck.craft?dl=0 Quote Link to comment Share on other sites More sharing options...
Wanderfound Posted March 8, 2017 Share Posted March 8, 2017 (edited) On 5 March 2017 at 2:35 PM, Camaron said: So, ages ago before my Kerbal playtime came to a near-standstill due to heavy college work and life in general, I found a craft built and presented by Rune that caught my attention for some reason, and I vowed to make a larger edition based on similar design concepts. Now, 14 months later (I know because of screenshot file dates), I came back to that idea and rebuilt a version that actually accomplishes all it was meant to do. This craft carries 12 Kerbals and a full set of drilling hardware as well as a polar scanning probe on board, to space in one stage with enough D/V to happily land on minmus to refuel. Theoretically it should reach anything in the solar system after that refuel. I wonder if anyone can point out significant improvements to the design? Also I will admit there are a few things clipped into the body, like some SAS and a single generator. Meet the Diamondback IV Where's the ISRU converter stashed? I don't know if it's possible to be very efficient while maintaining the aesthetics of that design, but as first impressions: 1) A ship of similar range and capability can be built with much fewer engines and much less complication in general. E.g.: 2) Balancing dihedral against anhedral like that on your wings is very inefficient from a lift point of view (the dihedral of one wing neutralises the anhedral of the other, but both wings have reduced lift relative to a level surface). You'd be much better off with a single-plane wing without anhedral or dihedral. 3) Large spaceplanes benefit hugely if you build in a bit of wing incidence. You want to be able to keep the nose pointed prograde while still climbing once you're up to speed. Lift with the wings, not the fuselage. 4) Drag matters. Drag matters a lot. You want to minimise the number of stacks in the design (i.e. reduce frontal area) and put into a cargo bay anything that doesn't absolutely need to be exposed during ascent. And, as mentioned above, make use of wing incidence to minimise fuselage drag at speed. 5) It's possible to build without clipping if you want. The design shown above has a very well-stuffed cargo bay, but the only clipping is incidental and marginal. The scanners are set up so they can open and operate without ever clipping through neighbouring parts. 6) Your plane looks as if it may be difficult to land on rough fields. Bigger landing gear and a more conventional tricycle setup with a wide wheelbase would help. A bit of low-G VTOL is helpful (belly Vernors etc), and drag chutes are essential for post-touchdown braking if you're planning on a Duna or Laythe landing. 7) Don't expect airbrakes to help much with reentry. They'll melt. 8) Where's your centre of mass? Your vertical stabilisers and rudders appear to be quite a long way forwards, and their effectiveness is in part a function of their distance behind CoM. You may get yaw stability problems, especially during reentry. 9) Do you have sufficient power generating capacity to run those drills and the ISRU? Edited March 8, 2017 by Wanderfound Quote Link to comment Share on other sites More sharing options...
AeroGav Posted March 8, 2017 Share Posted March 8, 2017 @Wanderfound all correct points, but I stopped at the "stage 1 mods", you're taking it stage 2, stage 3 unlimited class ! Yesterday I made a new version of my "Voodoo Ray" craft. What's significant is that it's a new method of controlling the ship , which might be the easiest way yet off getting something to orbit without sacrificing efficiency. The wings are angled to make lift with the craft set to prograde hold on SAS, but there's a deployable trim flap bound to the RCS action group. In one setting, the craft maintains very close to zero body AoA when prograde hold is set , with the wing's 3 degrees of built in incidence providing lift. The other trim flap setting gives you about 2.3 degrees of body AoA when prograde hold is set (more like 7.5 degrees when SAS is off) giving you a bit more lift for the phases of flight that need it. Other than making occasional heading corrections and staging the engines, the only control inputs you need to make are toggling between the two trim settings https://kerbalx.com/AeroGav/Auto-Ray Instructions - Spoiler Fly the aircraft to orbit with SAS set to Prograde hold. Use RCS action group to toggle between nose up trim and neutral trim. The aircraft starts off with nose up trim set. When the climb angle threatens to become excessive, with airspeed decreasing, switch to neutral trim. If you feel the nose is dropping too far, or if airspeed is encroaching upon the transonic region (240m/s), switch back to nose up trim. Initial climb angles of 10-15 degrees are "about right", but this will decrease as the air gets thinner. At some point, the plane will start levelling off and airspeed will start heading over 240 m/s even though you're in nose up trim. This means it's time to cross the sound barrier. Switch to neutral trim and use the abort action group to toggle the nukes on briefly. At 440m/s, press Abort again to cancel the nukes. Use nose up trim to bring the plane out of the dive but switch back to neutral to stop the climb angle getting excessive. Ideally, we want to maintain 440-480 m/s in the initial supersonic climb. After this, use the trim to try and level off at 12-14km for the speedrun. When airspeed exceeds 750 m/s, start using nose up trim to get into a climb and stop it rising any further. At 16km or whenever the speed looks like decreasing, press Space Bar to start the nukes. At 36km the Navball will switch to Orbit mode. Click it to put it back in Surface, otherwise it can lead to the plane trying to fly nose-down. Quote Link to comment Share on other sites More sharing options...
Camaron Posted March 8, 2017 Share Posted March 8, 2017 9 hours ago, Wanderfound said: Where's the ISRU converter stashed? I don't know if it's possible to be very efficient while maintaining the aesthetics of that design, but as first impressions: 1) A ship of similar range and capability can be built with much fewer engines and much less complication in general. E.g.: 2) Balancing dihedral against anhedral like that on your wings is very inefficient from a lift point of view (the dihedral of one wing neutralises the anhedral of the other, but both wings have reduced lift relative to a level surface). You'd be much better off with a single-plane wing without anhedral or dihedral. 3) Large spaceplanes benefit hugely if you build in a bit of wing incidence. You want to be able to keep the nose pointed prograde while still climbing once you're up to speed. Lift with the wings, not the fuselage. 4) Drag matters. Drag matters a lot. You want to minimise the number of stacks in the design (i.e. reduce frontal area) and put into a cargo bay anything that doesn't absolutely need to be exposed during ascent. And, as mentioned above, make use of wing incidence to minimise fuselage drag at speed. 5) It's possible to build without clipping if you want. The design shown above has a very well-stuffed cargo bay, but the only clipping is incidental and marginal. The scanners are set up so they can open and operate without ever clipping through neighbouring parts. 6) Your plane looks as if it may be difficult to land on rough fields. Bigger landing gear and a more conventional tricycle setup with a wide wheelbase would help. A bit of low-G VTOL is helpful (belly Vernors etc), and drag chutes are essential for post-touchdown braking if you're planning on a Duna or Laythe landing. 7) Don't expect airbrakes to help much with reentry. They'll melt. 8) Where's your centre of mass? Your vertical stabilisers and rudders appear to be quite a long way forwards, and their effectiveness is in part a function of their distance behind CoM. You may get yaw stability problems, especially during reentry. 9) Do you have sufficient power generating capacity to run those drills and the ISRU? Thank you. 1) ISRU is is chilling on the nose Also, the plane is as big as it is for maximum range AFTER a refuel at minumus, so a lot of the tank capacity is just empty cargo weight on the way up.I am well aware of the diminishing returns deal, but that's why these lessons on efficiency are so important to me. It's also why I use way too many wings to ramp up lift and reduce AOA - because they're also Liquid tanks so their mass isn't particularly wasted after leaving an atmosphere. 2) I know but it should be minor loss at a shallow angle and sometimes looks get in the way of function 3) It will be tricky to line up rows of wings at a slight custom angle but I will give it a try sometime 5) I got over clipping hangups a long time ago. My reasoning is basically that any sane aerospace engineer would have put things like the RTG internal to the ship, for example. 6) (Empty), this plane lands so easily i probably could do it blindfolded. The newer landing gears are surprisingly rugged. 7) I have found in several spaceplane designs now (Including this one) that the airbrakes survive fine and slow down the plane just enough to not blow to bits on the way down, in any case where the standard flat-belly approach isn't available. 8) Center of mass is roughly at the midline of the central liguid tank. With AeroGrav's help on the ingame drag simulation quirks, that may change significantly. 9) Simultaneously? Maybe not. Are two giants and some roof panels enough for a drill and converter? Quote Link to comment Share on other sites More sharing options...
AeroGav Posted March 8, 2017 Share Posted March 8, 2017 1 hour ago, Camaron said: 3) It will be tricky to line up rows of wings at a slight custom angle but I will give it a try sometime You got three choices Eyeball it in fine rotation moe (exact angle doesn't matter that much i find) Install editor extensions redux, allows you to create custom angle snap angles Hold down the shift key while tapping the rotate up or down keys when attaching wing to fuselage, this gives you 5 degrees. Not so easy to adjust after attachment though. Problem with your overlapping wings is that they'll end up looking like roof shingles. After doing an aero cleanup, my version of your ship makes about 2:1 lift drag ratio supersonic. My Space shuttle lookalike has angled wings and doesn't do much better, 2.5 to 1, because l/d ratio depends on the ratio of wing (low drag, high lift) to fuselage (high drag, low lift) as well. The space shuttle doesn't have anything like as much wing as your craft. Best I ever see supersonic is about 4.3 to one (big wings with incidence, skinny fuselage). One thing i must stress about adding incidence, angle your canard up by at least as much as the main wing so it stalls first. In fact if you want really stable, then have each wing have a tiny amount more incidence (fine rotation, smallest step possible) than the one behind it. The wings that start at the lowest aoa gain the most lift when the craft pitches up, since they are lower on diminishing returns curve, which makes it resist further pitch up and become increasingly stable. Quote Link to comment Share on other sites More sharing options...
AeroGav Posted March 8, 2017 Share Posted March 8, 2017 1 hour ago, Camaron said: 7) I have found in several spaceplane designs now (Including this one) that the airbrakes survive fine and slow down the plane just enough to not blow to bits on the way down, in any case where the standard flat-belly approach isn't available. The Diamondback has so much lift, it should re-enter very easy anyway. Lowering landing gear does a similar thing to airbrakes, but they don't overheat. Must be some special rubber compound in the tyres. The only reason it becomes a problem is because the cockpit is up front , exposed to heat. Mk1 cockpit , Max Skin Temp 2000K, Max Internal Temp 1100K - no heat bar appeared in my above video Mk3 cockpit , Skin limit 2700K, Max Internal 1500K - heat bar 75% full Options for a mk3? Well you could ditch the cockpit altogether, and the mk2 cabins. Control with a probe core, and fit a mk3 passenger cabin. 16 Kerbals for 6.5 Tons, instead of 12 Kerbals for 8 Tons, and much less drag (mk2 parts are horrible). 2.5m parts actually have the best drag/volume ratio by far, that includes the 2.5m resource converter, which is extremely slick provided both end attach nodes are covered. However, the 2.5m habitat is extremely squishy, the slightest scrape against terrain and you got 4 dead kerbals. Quote Link to comment Share on other sites More sharing options...
Wanderfound Posted March 9, 2017 Share Posted March 9, 2017 9 hours ago, Camaron said: 9) Simultaneously? Maybe not. Are two giants and some roof panels enough for a drill and converter? The large ISRU requires 30EC/sec, the large drills require 15EC/sec. The ISRU can outpace the drills, so the more drills the better (within reason; one is adequate, two is better, four is better still, six is getting a bit silly...). I normally use a pair of fuel cell arrays to provide the bulk of the power (deactivate them when not mining) plus a few of the small folding panels to supplement the fuel cells and provide power during normal operations. The roof panels may be creating a significant amount of drag. Quote Link to comment Share on other sites More sharing options...
Vanamonde Posted March 9, 2017 Share Posted March 9, 2017 We encourage you folks to give each other design advice, but please do so in other threads, since this one is for showing off your craft. Quote Link to comment Share on other sites More sharing options...
Wanderfound Posted March 9, 2017 Share Posted March 9, 2017 (edited) Kerbocrew Easy up. 11 Plenty of speed. Run the jets to their ceiling. Able to deliver 32 passengers up to a 500km orbit. Cobra reentry. Plenty of atmospheric cruising range. Spoilers keep the nose up during landing. Perfect for all your mass crew transfer needs. Craft file at https://www.dropbox.com/s/2sg6ph88bu55qqw/Kerbocrew.craft?dl=0 Edited March 9, 2017 by Wanderfound Quote Link to comment Share on other sites More sharing options...
Andetch Posted March 9, 2017 Share Posted March 9, 2017 On 08/03/2017 at 7:03 AM, Wanderfound said: Kerbotruck (AKA "you don't need that much wing") Andetch has always believed wings are only an optional extra on a Spaceplane, as the Widowmaker series demonstrates quite well! It must be said we like the weight/wing ratio on Kerbotruck! Due to someone in the R&D department taking the dangerous line of thought that maybe a plane that is easier to fly and land might be a good seller we are proud to give you the Widowmaker 2. However, it must be said that the consensus here is it has too much wing! Ship file at: https://drive.google.com/open?id=0BxP5XMEnEjPiQjVXLUo5NnV6NnMhttp://imgur.com/a/EtKii Quote Link to comment Share on other sites More sharing options...
Rune Posted March 9, 2017 Share Posted March 9, 2017 (edited) 1 hour ago, Wanderfound said: Kerbocrew (snip) Hey, another person using control surfaces as temperature-resistant airbrakes! Nifty trick, right? Oh, and if you deploy two on opposing directions, fiddling with the control authority can get you a pitch-neutral brake. Rune. Then again, the best airbrake is the main wing. Edited March 9, 2017 by Rune Quote Link to comment Share on other sites More sharing options...
Wanderfound Posted March 10, 2017 Share Posted March 10, 2017 Kerbotourist AKA "you don't need that much engine" Easy up 15 degree climbout Level off for the speed run Add the nuke at 20km Switchover at the jet ceiling Shut down the RAPIERs after lifting the apoapsis. Save a bit of oxidiser for the belly Vernors. Circularise on the nuke 2km/s unrefuelled 5km/s if you refuel Craft file at https://www.dropbox.com/s/mj1v83bvwho5ylv/Kerbotourist.craft?dl=0 Quote Link to comment Share on other sites More sharing options...
Andetch Posted March 10, 2017 Share Posted March 10, 2017 New from Andetch Spaceplanes - The Wingless Wonder - because wings are over rated! Caution, may result in crashing into the runway on takeoff. Okay, there are little tiny wings, so isn't 100% wingless, but I think you will have trouble making an SSTO with less wing! I dare thee to try and get a horzontal launch with less wing into orbit! Quote Link to comment Share on other sites More sharing options...
AeroGav Posted March 10, 2017 Share Posted March 10, 2017 AKA "You really don't need that much engine" 19 Kerbals. Over 50 tons takeoff weight. No oxidizer. One Rapier. Two Nukes. Not only does it make orbit, it did so with over 2600dV remaining. On it's maiden flight. Quote Link to comment Share on other sites More sharing options...
hurdurdur Posted March 15, 2017 Share Posted March 15, 2017 50% trolling , 50% on the money - ssto with 4 parts: Parachute makes landing easier even after wasting a lot of fuel to get up there (due to bad flying). Quote Link to comment Share on other sites More sharing options...
9t3ndo Posted March 15, 2017 Share Posted March 15, 2017 (edited) Nothing Special use for it, just an two seater SSTO. Has 6 Rapiers, 2 Nervas and plenty of fuel. Download Edited March 15, 2017 by 9t3ndo Quote Link to comment Share on other sites More sharing options...
Andetch Posted March 16, 2017 Share Posted March 16, 2017 (edited) 4 hours ago, hurdurdur said: 50% trolling , 50% on the money - ssto with 4 parts: Parachute makes landing easier even after wasting a lot of fuel to get up there (due to bad flying). Best SSTO ever.... Although using a planned exit from the vehicle over water you could do away with the parachute Edited March 16, 2017 by Andetch Quote Link to comment Share on other sites More sharing options...
Wanderfound Posted March 17, 2017 Share Posted March 17, 2017 (edited) Not quite SSTO, but close enough. Testing how much range I can get unrefuelled while still being fully equipped and pleasant to fly: Munjet Science bay equipped; swap for a passenger cabin for a tourist ship. Easy takeoff. Climb out on the first set of drop tanks. Dump the first droptanks after going supersonic. And the second set around Mach 3. Level off for the speed run. Zoom climb before you cook. Add the nukes at 20km. Fifteen seconds of oxidising rocketry to get the gravity lift going. Finish on the nukes, nose down to minimise drag. More than enough for a Munar landing and return. Excellent heat tolerance allows aggressive aerobraking on the return. Craft file at https://www.dropbox.com/s/c286hizhfh6repv/Munjet.craft?dl=0 Edited March 17, 2017 by Wanderfound Quote Link to comment Share on other sites More sharing options...
*MajorTom* Posted March 18, 2017 Share Posted March 18, 2017 (edited) My "2 Strange" early and low-sci parts Mun stock mission, 7panter engine. This is a 10tonn of payload SSTO-freighter. Sorry i lost pics somethere... so today - only video. The Mun-ship is also interesting - i put this ship inside 2x*mk2 cargobays (without clipping parts inside each other). ps; sorry, please, for my poor English Edited March 18, 2017 by *MajorTom* Quote Link to comment Share on other sites More sharing options...
Planetace Posted March 18, 2017 Share Posted March 18, 2017 Why do planes? GO BIG! Quote Link to comment Share on other sites More sharing options...
hurdurdur Posted March 18, 2017 Share Posted March 18, 2017 For a while i wondered if aerospikes are good enough on their to make a space plane... In this configuration it certainly is: The flat profile and wings make aerobraking back a breeze, can easily do from 200x75 orbit landings without even showing any overheat signs. On takeoff the throttle has to be let back a lot since there is no point to burn fuel for speed at lower altitudes, over 2.5km the aerospikes go over 300isp and just keeps on getting better from there, there's plenty of fuel for maneuvering once you reach orbit. In the storage are at the nose i hid batteries, backup control unit and a small reaction wheel, plus solar batteries to charge up electricity on orbit if necessary. As seen from the picture this is robust enough to even land on fields when coming back down. Can briefly spin out of control when doing a rapid aerobrake but mass balance is just right so you regain control with ease. Might be a useful design for planets without oxygen but having a thick enough atmosphere. Playing with fuel mass may even make it possible to land this guy reverse on Duna ? Quote Link to comment Share on other sites More sharing options...
Andetch Posted March 18, 2017 Share Posted March 18, 2017 @*MajorTom*, your machine has real nice graphics there! My KSP looks like it is ran on a C64 in comparison! Also, loving the low tech aspects! I must say I prefer the challenge of low tech craft - getting to mun with very limited science is the biggest challenge, harder than getting to Eeloo on Sandbox. Quote Link to comment Share on other sites More sharing options...
Wanderfound Posted March 19, 2017 Share Posted March 19, 2017 (edited) Kerbotruck Compact Lander √ 110,000 for the truck, √ 70,000 for the cargo. Make sure to set the control to the cockpit before takeoff. Easy up. 10 degree climbout. Easily through transonic while climbing. Level off below 20,000m to build speed. Pull up before you cook. Switchover at the jet ceiling. A quick tap to circularise. Well-stuffed cargo bay. Around 8,000m/s from the nuke transfer ship while pushing the lander. 4,700m/s ΔV in the lander. Full science kit and probe autopilot, capsule equipped for interplanetary reentry speeds. Very easy to redock. Fuel cost on the fully-recoverable launcher is about √6,000 after recovery, plus √ 70,000 for the non-recoverable spacecraft. Moho on the cheap, or as many Joolian moons as you care to visit. Craft file at https://www.dropbox.com/s/ebs86yg1vt2qgxk/Kerbotruck Compact Lander.craft?dl=0 Edited March 19, 2017 by Wanderfound Quote Link to comment Share on other sites More sharing options...
eagle92lightning Posted March 20, 2017 Share Posted March 20, 2017 On 3/3/2017 at 1:23 PM, Jett_Quasar said: OSIRIS Download on Kerbal-X: https://kerbalx.com/Jett_Quasar/craft - Jett Okay I downloaded this craft and every time I go to use it tilts backwards. Is there anyway I can fix it? Quote Link to comment Share on other sites More sharing options...
eagle92lightning Posted March 20, 2017 Share Posted March 20, 2017 On 1/20/2017 at 4:03 PM, Jens Lyn IV said: Derp derp herp* derp, derp hurr herp (durr) derp derp; durr hurr derp. Herp, herp derp herp hurr, derp-derp derp. Derp. Herp derp. Hurr durr. Derp derp derp. *Derp. Derp Quote Link to comment Share on other sites More sharing options...
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