AeroGav

Can also happen if you rotate the control surface 180 degrees when attaching it - for example, if you attach the elevon to the leading edge of a wing instead of the trailing edge, it will almost certainly move the wrong way. Easiest fix, if you don't want to change your design, is just set the "control authority" slider to a negative number, for example if it was 100%, set it to -100%. Often have to do this with leading edge slats, for example (they don't work like in real life!)

Can anyone help me make an engine config file ? I know you should probably learn to walk before trying to run, but if I just needed a simple Kerolox or Hydrolox engine i wouldn't be trying to do my own. I am trying to create a bimodal NTR with two modes : Mass 1.75 T Mode 1 - NTR mode. Fuel is 100% LqdAmmonia. Thrust 400kn. Vac ISP 520 seconds, Atm ISP 312 Mode 2 - Afterburner. Fuel is Hydrolox, with a ratio of 3KG Oxygen per 1KG Hydrogen burned, Thrust 600kn, Vac ISP 642 Atm ISP 480 Yes, this is meant to be for a near future Shuttle 2.0 The NTR mode with storable, dense Ammonia is an upgrade on the hypergolic OMS, while the afterburner mode is used on launch, running off the external tank and thus can use cryogenic propellants, since boiloff is not a concern. I tried modding the BiModal NTR (which comes with stockalike) by hand, but I keep getting error unkown RESOURCE {LqdAmmonia Ratio 1.00 } when selecting this engine, and it has a thrust and an ISP of zero when not in afterburner mode. I suppose i could just use two sets of engines instead of a bimodal, since that ups the difficulty , but apart from the wastefulness of this approach, i am not aware of any ready made engines for NTR with Ammonia anyway

I think it's an immovable force vs irresistible object problem. If a huge , fast wave strikes something that is able to float and move, the maximum amount of kinetic energy the structure has to absorb is equal to the amount needed for the airplane, or car, to match velocity with the incoming wave. The problem with being in a car or a plane is that you might then get dashed against a cliff (or a building that is still standing, but if we're really talking about a wall of water going 100mph there won't be any of those). On the other hand, a building fixed to the ground has to absorb a quantity of energy several orders of magnitude greater - it must bring the wall of water to a stop across a front equal to the width of the building , or break. To put it another way, would you rather be in your car as it gets dropped from a crane, nose first into the ground, impacting at 30 mph, or in a concrete building being dropped from the same height. The steel skin of your car is only 1mm thick (though there are some sturdy girders and frames at points) and the walls of the building are much stronger. But , the car will obviously do better (modern crash test standards are much more severe) because the impact force is proportional to the weight of the object being dropped, and your car has a much better strength/weight ratio, before we even get into crumple zones and airbags. I guess from what people have said , 100 foot walls of water moving at 100 mph are something that only happens in hollywood disaster films with bad science. The main danger seems to be getting caught in the open, getting swept away inside a car, or being in a building that collapses when the wave hits. https://www.ntsb.gov/investigations/AccidentReports/Reports/AAR1003.pdf Re: the Hudson Ditching, the Airbus entered the water in the following condition 125 knot airspeed 12.5 feet per second descent rate nose pitched up at 10 degrees This tore off one engine, tore off the fuselage skins under the last dozen row of seats causing it to submerge almost to roof level by nightfall. However, a building being catapulted into the Hudson at the same angle and velocity would disintegrate immediately, if we're still considering the Hollywood Tsunami scenario.

Blocking thrust is an "all or nothing" phenomenon. So if you think the front engines are being blocked, activate only those engines on the runway and see if the craft moves. the inboard engines appear to be blocked by the rear wing cluster. btw i'd change those mk2 fuselage pieces for 2.5m, which have less drag and hold more fuel

One for career mode ? Tier 7 tech space plane that can launch from Tier 2 Runway and Hanger, can be researched with Tier 2 R&D facility. In fact, I have deliberately excluded any items that are not on a prerequisite tech node for the Panther or NERV engines. https://kerbalx.com/AeroGav/Kranker Flight envelope here, as reported by Kerbal Wind Tunnel. Note, KWT does not at the time of writing take account of orbital free fall effect, so at mach 4 and upwards it cruises a lot higher than indicated. It is useful for showing best way to beat sound barrier however and it indicates that the craft would probably make orbit in fully re usable mode, even if you don't activate the final stage and punch off the jets. Chart on left is for jet power only. Middle chart is performance with NERVs active, right picture is with jet stage separated. Flight tips The airplane's wings are angled up and will make lift even if the nose is on prograde. It also flies a degree or two above prograde even when prograde hold is set, and the nose rises a few degrees further if SAS is taken off completely. You can more aggressively force the nose down by activating Orbit mode on the Navball while in Prograde Hold mode, since this makes the airplane attempt to point its nose at the horizon, rather than the prograde marker, which is likely climbing. Abort action group toggles nukes. Jettison the jet engines once their tanks empty. Once you've lit the nukes, stay on Prograde Hold mode and keep Navball in Surface mode until passing over 70km.

You don't want the nose getting more than 5 degrees above prograde as the drag gets to be horrendous. When you are no longer producing enough lift with nose 5 degrees above prograde and the climb starts levelling off, is when you will hopefully transition to supersonic flight. If it is unable to do so, you either have not enough power, too much drag, or not enough lift, because if you had more lift you could have done the supersonic transition at a higher altitude. Too much wing causes problems for your air breathing engines. You will either have to run a lower angle of attack than optimal, or find yourself getting up to altitudes where the engines can't make good power before they've maxed out mach number wise. A space plane that climbs to orbit with chemical engine power also has a TWR well above 1 in rocket mode, so lift to drag ratio in rocket mode doesn't matter as much as getting dry mass down. NERV powered space planes have much less power in rocket mode and very heavy engines, they need a lot more wing and a good lift to drag ratio in hypersonic flight. @Arugela I strongly recommend you install Kerbal Wind Tunnel It gives you a nice graph showing excess thrust at every speed and altitude, showing you when you can get supersonic note - it only takes account of engines on the first stage - it takes account of landing gear drag so you need to raise them before running the analysis - does not take account centrifugal effect from very high speed flight that reduces your apparent weight as you get up near orbital speeds - it works in 1.5 just with the odd hang, like it did in 1.4x

Only these screenshots. It's not very stable in yaw (not long fuselage, tail too small) and knowing what i know oow, I'd use Bg S strakes instead - more capacityy of fuel per mass and drag. airbreathers still attached getting on my nervs... a bit hot at mach 13. lost the small nose cone.. had to throttle back slightly at this point to avoid losing any more parts, but not too much or you don't make orbit. procedural faring for mk2 i think

Yeah a lot of work goes into making something in FAR. A high speed airplane that can land at speeds the small retractable gears can survive ends up looking like my plane, lots and lots of wing parts, and sophisticated high lift systems. No way in hell of getting it under 30 parts nor of getting landing speed below 60m/s , which the fixed landing spats probably cant handle

Can changes in the hardware of the pc running the game cause differences in behaviour like this ? If you're getting into rounding errors, then surely FPS differences will influence those ? Does the Unity physics engine take advantage of different code paths on different processors (AVX etc) which might cause differences in the way floating points get rounded up or down, different precision levels?

Might be easier if the carrier is moving, since that means less speed difference between the carrier and the airplane.

Damn, after rewatching that video i realised i took off with the parking brake set. Thought it was sluggish :-/

Mk3 cabins seem quite rigid. I think if you attach one pair of big S to every mk3 fuselage you'll be ok, but as you say there is a limit to how much force you can put through each wing/fuselage joint before it snaps. I have a non-nuke version of that long plane that is 30% heavier and has half as many wings, the force per wing is higher and when you pitch up to take off, it is very easy to snap the wing.

I;ve been busy the past two weeks https://kerbalx.com/AeroGav/Monstrosity-225L https://kerbalx.com/AeroGav/vagabond-ssto https://kerbalx.com/AeroGav/Sparrow Anyone need a 43 seater shuttle ? Probably not..https://kerbalx.com/AeroGav/Hammerhead5 https://kerbalx.com/AeroGav/SX-60L Of them all, the one that earned the most downloads and likes by far is the one below, a mod of someone else's bird. This is despite the fact it's probably the hardest craft to fly that i've posted on KerbalX in years. It seems looks really are everything, not handling, not capability, and even niche seem to affect that much. Finally , I'd like to showcase this Panther NERV Tier 7 career plane. Only needs the Tier 2 Research building. every component other than the nuke engines are the lowest tech items available https://kerbalx.com/AeroGav/Foxbat Kind of reminds me of a Flanker, except for the canards and lack of tailplane. The base version will reach 4million km ap and is easy to fly. Here's an example outfitted with drop tanks, which can explore cis-munar space https://kerbalx.com/AeroGav/Foxbat-with-drop-tanks https://i.imgur.com/qiq9vgr.jpg

Another Tier 7 for you all, apart from the nuke i've tried to keep everything else as low tech as possible https://kerbalx.com/AeroGav/Foxbat It can be outfitted with drop tanks like so https://kerbalx.com/AeroGav/Foxbat-with-drop-tanks

Preamble Most people building Space Planes use RAPIER engines, however you are unlikely to see those till the very end of career mode, being Tier 9 (1000 Science points). While not as popular as RAPIER designs, Whiplash Space Planes aren't uncommon, but as Tier 8 engines, they have a Science cost of 550, which means you aren't getting them without a max level R&D building. And that's a hugely expensive upgrade, given that funds tend to be harder to acquire than science points. So, for 90% of our career game, the only realistic engine option is the Panther. It's a fine engine, but it's thrust output peaks at mach 2.5 and goes to zero by mach 3. Realistically, your space plane is not getting much above mach 2.5 on jet power, and that means your rockets need to add another 4.5 mach's worth of velocity to reach orbit. On chemical engines, this requires a very large fuel fraction that leaves little room for payload, and that payload fraction soon disappears altogether if you attempt to go beyond low orbit. However, you can get NERV engines with a Tier 2 science building, and with over twice the ISP you don't need to turn your craft into one big fuel tank just to reach orbit. These engines do have a miserable TWR of course - the measly LV-909 Terrier has the same thrust, but weighs just 0.5 tons instead of 3. Your vessel is never going to have a TWR > 1 or even close to it. For a rocket, this is a major problem. However , you have to remember that your spaceplane is an airplane and it does not need a TWR over 1 to fly. The engines will be thrusting horizontally to accelerate you to orbital velocity, the wings take care of gravity, to stop you plummeting to the ground. So long as your thrust exceeds drag, and the wings are making sufficient lift to counteract gravity, you will go to space today. Lift to Drag Ratio Angle of attack is the difference between where the nose is pointing and where the airplane is actually going. For wing and control surface parts, lift and drag are both zero, at zero angle of attack. As AoA goes above zero, lift increases rapidly, but is subject to diminishing returns. After 30 degrees , lift starts decreasing with further increases of AoA because you've stalled. Drag increases steadily with angle of attack, all the way to 90 degrees. Non wing parts also produce more drag with increasing AoA, however they still produce considerable drag even at zero AoA. They also produce little or no lift. The important things to remember from this - In supersonic flight, best lift to drag ratio happens at about 5 degrees ApA. Unlike real airplanes in KSP, the wing generates less than 20% of the drag your craft is producing. Some parts are very draggy. Solar panels, even deployable ones, need to be in a service bay. 1.25m bicouplers are meant for use on rocket stacks, and are very draggy on an airplane. Mk2 fuselage parts should be avoided, they make 250% of the drag of a mk1 part of the same length and fuel capacity. Mismatched attach nodes create massive drag. A 1.25m attach node should only ever join to another 1.25m node. If your fuselage is tapering down to 0.625m, use an NCS adapter to smooth the transition. If it's flaring out to a mk2 cargo bay, use a mk1 to mk2 adapter short. That second point is counterintuitive - people often reduce wing area thinking it will reduce drag, but you end up needing a higher angle of attack to get the same lift, or flying at a lower altitude where the air is thicker. When on jet power, a smaller wing can improve performance, because at lower altitudes your engine can make more power. Once you've staged in the nukes however, you are burning fuel rapidly and it's all about getting the best exchange rate possible when converting your precious forward velocity into lift. This means, angle the nose for 5 degrees above prograde. It doesn't matter whether prograde is showing a climb or a dive -- just point 5 degrees above where it is pointing. NERV in practice - Building an Airplane The basics aren't all that demanding One NERV for every 12 tons or so of airplane One Panther for every 2 NERVs About 30% of the craft's weight should be fuel. 2 MK1 liquid fuel tanks are enough to get a basic 2 nerv design into orbit. A lift rating of 7 to 10 per 20 tons is about right. There is a lot of wiggle room here, but in general more wing makes the NERV powered part of the climb easier, at the expense of the jet powered part. Avoid using mk2 parts due to their high drag, only if you must have a cargo bay. Mk1 parts are not as heat tolerant, so use an inline cockpit as it will be protected by the nose cone, intake or service bay in front. The majority of your effort should be in making sure the airplane is stable and easy to fly with precision. This will make the flight more enjoyable and allow you to maintain the angle of attack values where lift to drag is good. The major issue is balancing the heavy engines with non fuel parts, and keeping the fuel amidships, so there is no centre of mass shift between full and empty. For example, this works - Cockpit, Passenger Cabin, Engine Nacelle intake, 2 fuel tanks, then our Panther. The nukes are either side. RCS build aid is on , but you can't see the red ball because the dry CoM is in the exact same place as the wet one. We have 6T liquid fuel for a total mass of 17T. About 30% fuel so that's good, the engine to mass ratio is good too, leaning slightly on the overpowered side. Now we just add wings. Canard or Tailplane design is totally up to you, just make sure your wings don't get in the way of the exhaust plume. Since the first pic is of a canard version of this airplane, let's go with a tailplane this time. And there we go . As you can see, Kerbal Wind tunnel shows if your design has enough power to go supersonic, and what its top speed will be at every altitude. Note, it takes account of drag from landing gear, so you need to raise the gear before running this analysis, or just do it before fitting any like i did here. Note also that you can bind your nukes to an action group so you can turn them on between 300-400m/s if your design has trouble busting mach 1 on jet power alone. Note how the blue arrow is towards the back of the yellow ball. Centre of lft must be behind centre of mass, but excessively aft CoL will suffer excessive drag, because you need to generate a lot of force with the control surfaces to get the nose up to make lift. Large deflection angles on your control surfaces are draggy. That is why it is better to fit generously sized ones and use the "limit authority" slider than use tiny ones that are maxed out. Because we used RCS Build Aid to ensure that our centre of mass does not change as fuel burns off, we can get away with having CoL fairly close behind our Centre of Mass. Test Flight A complaint I often hear about spaceplanes is that you waste 20 minutes getting to altitude on every failed attempt. However, there is a lot you can learn without getting above 500m. Take SAS off, and attempt to stall the plane, how controllable is it? Throttle up and down, does the nose rise and fall, have you got a centre of thrust problem? Does it break mach 1 with one panther per 20 tons? If it can do so, without being ridiculously overpowered, then its not got any drag problems that will stop it from flying under NERV power. Of course , Kerbal Wind Tunnel will tell you this without even needing to leave the hangar. If all of the above is true, and you are flying a sensible profile, and have stuck to my recommendations regarding engines per ton and fuel mass percentage, it should make orbit !

I 'm rubbish at gravity assists. Had about 880dv left coming into jool system. a combo of aerobraking and grav assists should be possible, but i spent 4 hours bouncing back and forward. https://www.dropbox.com/s/tj0lq19a0njhyjv/POCKET BILLIARDS.sfs?dl=0 That's the save file if anyone can do better. Eventually did a laythe-tylo-laythe braking manoeuvre that drops my PE about 10km inside jool atmosphere and has my AP halfway out to Vall, used the cheezy technique of going to the reacking station when i didn't want more aerobraking off jool, and riding the plane when i did, gradually dropping my orbit bit by bit till finally got a laythe encounter at a speed i could aerorake into the atmosphere from. When it came to landing, i discovered this craft isn't really robust enough to land on uneven terrain with 60 tons of ore aboard. My designs usually have no problem setting down on laythe, but this took a dozen attempts and a bit of luck. I used hyperedit to bring a rover with a resource converter onboard to our airplane so as to unload the ore and refill the fuel, and set off for home. Without ore aboard, takeoff was easy and we still had 4800dv left after getting into orbit around Laythe. A simple direct burn back to Kerbin was done, upon entering Kerbin SOI we had over 2000 remaining. We were too fast to aerobrake all that off, and could only drop to 57km without damage, so i could have used a resonant orbit to get a second nibble at aerobraking at a more reasonable speed - but that would have added 20 years to the mission ! So I just retro burned shortly before dropping into KErbin's atmosphere, about 1000 m/s worth, which in turn let us drop deeper and aerobrake more without blowing up. 3 or 4 passes later, we get down. Will ad vids, but feel burned out by this . Edit - video Well, did the Krebin to Laythe leg in under 3 years and that was 60t of ore, (departed day 226 of year 2) but not really so practical, i should have used a mk3 airplane for this payload, and it wasn't all that much fun beyond constructing the aircraft ! Better luck for the rest of you!

Because I think the OP does not want the cargo to be transferred. It stays in same vehicle from surface of kerbin to surface of laythe. Also my spaceplane doesn't have that much extra dry mass compared with a dedicated transport - 2 rapiers, 3 panthers, and a bunch of wings - but you'll need to add mass to the interplanetary ship to make it landable.

I'm not sure they are OMNI, I have had problems when inadvertently mounting them backwards on a plane before (engine starts coughing once speed gets up). Intake air is based on two values, a static one and a ram air rating. The ram air rating goes up with increasing speed , though some of the low speed ones (radial supersonic intake , i'm looking at you!) start heading back down to zero again once you go past their peak. The static rating is fixed, and the pre cooler has the highest static rating of any intake, so it will work mounted backwards up to about 50m/s, then the negative ram air number overcomes the static rating and causes insufficient air.

Boeing is a private company. What NASA have been perfecting, for the past 30 years, is an arrangement that combines the very worst aspects of government institutions (conservatism, bureaucracy, make-work g) with and private greed (profiteering, doing the absolute bare minimum) on monopolistic, open ended cost plus contracts that reward failure. NASA should either do thing in house, "in source" like SpaceX is doing, or tender them out on dollars per ton contracts. I wonder where we'd be right now if the SLS and Constellation money had gone to SpaceX and Blueorigin instead.

I just reread this. Up until the the bit about drag, the basics of centre of mass, centre of lift and thrust torque still stand. The drag stuff is now wildly incorrect. The stock aero model does not care about wing shape, Hypersonic wing vs subsonic wing can be the same shape. Just get your centre of mass / centre of lift right and avoid the part attachment mistakes that cause abnormally high drag.

I'm struggling to stay focussed on this mission because at the end of the day it's just a flight to Laythe, but anyway. Here is footage of the NERV engine ascent to orbit. This thing is pretty underpowered, only 6 nervs pushing us. Fortunately , our lift to drag ratio is pretty damn good, over 3.5 to 1, which makes it all possible. The 2.5m crewed bits and ore tanks have surprisingly low drag, and wing parts tend to bring up the average too - and we got a few of those (!) After reaching orbit, we dock with my orbital fuel depot, which is resupplied from a Minmus ISRU operation. The place is called Gus' Gas, and like most truck stops they offer a few extra amenities besides fuel. Haldorf purchases one of the giant Terry's Chocolate Orange's and the 4 x 2L K-Kola Value Pack. Tramal takes the other Orange as well as a paperback called "50 shades of green", while Padorf uses his jetpack to obtain a series of periodicals from the top shelf of the magazine rack. Sadly for me the actual pumping gas part was no fun at all. I usually build self refuelling spaceplanes with their own mining gear, having to manually transfer to every damn strake on this airplane was a miserable job - and i've got to do it all again when i reach Laythe..

Ah sorry I didn't realise the discussion had moved on to Ferram Aerospace. IT is much more realistic, and avoids the drawback mk2 parts suffer in stock aero

About a year ago I started a Ferram career game. Everything takes so much longer to design , looking it the craft files it appears i lost interest in the middle of designing a two stage to orbit panther/terrier spaceplane (panther gets dumped) Anyway this appears to be my Juno terrier ssto, i can't remember how it flies because i don't have a ferram install to hand... can't remember if its supersonic or not on jet power. If not I assume the highly swept planform was just to lower drag when running on Terrier power. TWR with the Terrier is only 0.49 to 1, so it needs to have good lift drag ratio in supersonic flight https://www.dropbox.com/s/fsnx3rcm6ikxcr6/Junovator.craft?dl=0 Obviously, high tech stuff like retracting gears and inline cockpits would disqualify it for the challenge.

It's all there in the F12 menu The Big S Delta Wing is generating 15 times as much lift as the MK2 fuel tank, for half the drag. It is holding 75% of the fuel too, for half the drag. The MK1 fuel tank is about 40% of the drag for the same fuel capacity. Cylindrical tanks are best at holding fuel as far as weight is concerned. But, the thing which holds most fuel for a given amount of drag is the big S wing strake

Then what do you think about Phobos and Deimos ? Better ?