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Okay, so in pursuit of orbital tourism contracts in my first career game, I designed my first spaceplane. Not a HOTOL SSTO, just a fancy-looking Dynasoar equivalent -- boosted vertically, maneuvers in orbit with a rocket motor on the aft end, reenters and lands more or less like a Space Shuttle (except parachute recovery at the very end, because my R&D hasn't produced retractable landing gear yet -- hey, give me a minute!). A little "simulation" testing (launch and revert) verified that the orbiter handles well enough in both boost and glide, and even reentry -- and a little tweaking on the booster got it under control during the early parts of boost, when there's a lot of aero force available on those wings (swivel engines and fins on the boosters FTW). Everything was great until I'd been reentering for five minutes or so -- starting from a 75 km orbit, I set up a periapsis of 48 km. I held approximately 30 degrees above prograde through reentry, though that tended to drift in a pitch-positive direction (because I was using heading hold while flying around Kerbin). When I was getting down a bit, I started to run low on battery, and since I had way too much fuel on board anyway, I ran the main (Swivel) engine at low throttle to get some power from the alternator, but I don't think the thrust was enough to contribute to the heating issue (well below what was needed for level flight in earlier atmospheric testing) -- but by the time I was down to 39 km, both the Mk. 1 Cockpit and the RCS sphere in the chin position were very close to their temperature limit (but the Crew Cabin, main wing, canard, and 800 fuel tank weren't even showing thermometers). That's the point at which I reverted the flight, hoping the problem was simply one of reentry profile. I'm aware that reentering too high will burn away an ablator with little braking effect, while going too low will overheat things and/or kill Kerbals due to excessive G loads; I'm sure there's a similar tradeoff in reentering a spaceplane. I just don't know what it is. Here's a VAB image of the vessel as flown. I've since pulled half the Lf/O out of the 800 tank (might replace it with a 400 tank, if that proves helpful, though I really need the length to keep the COM from moving too much as main fuel burns off), moved the monopropellant sphere inside a service bay (between the crew cabin and reaction wheel) and mounted a pair of batteries inside the service bay as well -- but I doubt that'll have much effect, other than improving my ability to make a couple orbits and still have electricity to operate the SAS and reaction wheels. Booster has Swivels on the core and the two boosters that also have fins, Reliants on the other boosters. Asparagus staging dumps the Reliants first, keeping the Swivel boosters until atmosphere is thin enough the wing doesn't want to make the stack flip end over end. The 10+ T orbiter reaches orbit with a full tank, if flown optimally, which means if I can lick the reentry this Taxicab generation could also fly tourists on Munar flyby missions. Would I be ahead to reenter higher, lower, or at a higher or lower angle of attack, or am I just approaching the whole spaceplane thing wrong?

Sorry for the lack of screenshots: I'm not home a/t/m, but this has been bugging me. With sufficiently advanced tech and a bit of trial-and-error, I've been happy to find that landing capsules is pretty "easy button.": Enter a low (<100km) orbit Drop periapsis to 40km Turn on SAS Set SAS to keep the nose pointed retrograde Watch the lightshow pop the 'chutes. This is pretty much the same regardless of what other stuff I have hanging off the back of the capsule - cargo bays, empty fuel tanks, science containers, etc. With a heat shield, enough radial-mount parachutes, and a reentry speed <2600m/s, it's pretty safe. The problem is specifically when I have a "tourist box" consisting of a Mk1-2 command module on top of a hitchhiker container and a heat shield. Very simple, right? Except it wants to tumble - even with SAS on, it'll spend a good chunk of the reentry stuck about 20 degrees off-axis. I've got plenty of electricity. They're surviving reentry, and I know that any landing you can walk away from is a good landing, but I won't lie - it makes me nervous. Is there something inherently off-balance about the hitchhiker container? Is there a way to balance it better? Or maybe change the aerodynamics of it so it's more stable? (I could put on some reversed tail fins... or would that interfere with takeoff?) TIA

I just lost an expedition (six tourists, one pilot) because the Hitchhiker exploded during reentry on the way back from the Mun, despite having a 2.5m heatshild directly attacked to it. Why did this happen?

I’m currently designing an Eve spaceplane mission. I’m very excited for this mission and so far quite pleased with my craft. The mission profile looks like this: 1. SSTO from Kerbin 2. Refuel in LKO with fuel tanker (capable of Minmus refuel with ISRU if you’re not lazy like me) 3. Fly to Eve and land 4. Refuel on Eve with ISRU 5. Staged ascent from Eve, with only the cockpit eventually making it back to Kerbin. Anyway, I digress, none of this is too relevant to the question. My issue is that I cannot for the life of me reenter the plane on Eve. I will burn up every time seemingly regardless of my entry profile (shallow vs steep and several in-betweens). Are heat shields a must now? And how to put heat shields on a plane that’s supposed to SSTO from Kerbin without totally ruining the areo? Any help is appreciated. I will say I’ve had lots of fun looking at the firework show each time I’ve blown up the 150-part plane during my tests!

So I remember atmospheric heating being a bit of a joke back when it was introduced in 1.0 - even with difficulty set to max and Deadly Reentry installed, it was child's play to survive reentry. However, I'm really struggling with the current version, and most of the threads I can find are either out-dated, unclear, or actually contradictory, so I have some questions. FWIW I currently have re-entry heat set to 100% and the latest version of Deadly Re-entry installed (although I'm not clear on how much difference that makes!) and am playing in the stock Kerbol system. How exactly does your trajectory relate to re-entry heating? The 'common sense' assumption seems to be that a shallower trajectory is safer, but I've also seen people argue that it exposes you to heating for longer, therefore total re-entry heating is greater. Is it basically the case that a steep trajectory minimises heating, while a shallow trajectory minimises speed and g-forces? How is re-entry heat determined? Presumably the higher the speed and the denser the atmosphere are the key variables. How exactly do angle of attack and your vessel's aerodynamics affect heating? What about mass/weight? Does having radiators affect re-entry heating at all? How exactly do heatshields work? Is there a certain temperature threshold at which they stop increasing in temperature and start burning ablator instead? What determines the rate of ablation? Why is it that once the ablator is used up, the part seems to explode instantaneously, rather than only when it reaches its temperature limit? What's the deal with spaceplanes? If I ever get above about Mach 3.5, I start exploding. Is this a simple function of velocity vs altitude/pressure? If so, is there a guide somewhere as to what speeds are safe at which altitudes? Does angle of attack make a difference, and if so how? What about the shape of your plane? Any tips for surviving EVE reentry? Do people generally consider reentry balanced at 100% reentry heat setting with Deadly Reentry installed? Should I just give up and turn it down? Or should I uninstall Deadly Reentry? Does anyone have any recommended thermal settings?. Really appreciate any help people can give, so thanks! Have a feeling there were some other questions I've forgotten as well... EDIT: Forgot to ask, are there other decent strategies for plausible re-entry vehicles besides heatshielded capsules and shuttle-style spaceplanes?

It happened to Scott Manly and it happened to me a lot: The mk1 and mk2 cockpits burn up during reentry. Nothing seems to help. Maybe you can help by analyzing Scotts accident. It happened at 7:20

So here is a question I have been trying to find an answer to but have had no luck. How does heat on the ship during re entry work? In the instance of heat shields or just standard non heat shielded parts, is it the lead point that takes 100% of the heat or is it heating any point at all that is not parallel to entry angle. Basically here is the back story that leads to my question. I am using stage recovery mod because I like the realism of being able to recover stages. Because of this each stage has parachutes and other things designed to slow down my stages. On my main stage (4 nerv's a orange fuel tank and some struts) I put 1.25s on top of the mark1 liquids and a 2.5 on top of the orange. during aero breaking with my pod attached the 1.25s that are set back a few meters from my pod but open to the elements were taking no heat (no ablator loss) but my lead point on the pod was. Is this how it works? To simplify I have a new stage I'm making (screen shot attached) will the engine take all of the heat and not the shields, or will the shields take the heat since they are also at a perpendicular angle to entry? Thanks in advance.

HI I have a problem with my space shuttle when I going pack to the space center. When I enter a point around 40km to 30 km. I lose ful control of the shuttle and it is spinning and hurling. I have been using this shuttle for a very long time and never had a problem whit reentry. What are wrong and how do I fix it??

I was playing ksp coming from minmus, but on re-entry, something wired happened. It refused to simulate drag. The spacecraft was at 900 m/s and accelerating at 2 km. Therefore, I couldn't deploy the parachutes.. Anybody else have this problem?

Hello guys, how are you doing? I have started playing KSP two days ago and I can't express how much I am enjoying the game, not only the successful missions but the unsucessful ones aswell, in which I learn the most. At the moment I have put 2 rockets into orbit. Everything went fine with the first one, it landed perfectly (didn't explode lol). However, I am having a problem with reentering my second mission. The thing that differs the 2nd from the 1st is that the second one has a MK1 Crew Cabin for tourists. In the screenshots i've taken is possible to see my current orbit, fuel situation and the rocket itself. Problem: Once I lower the Periapsis to ~37km, I use the decoupler and wait for the reentry, always aiming retrograde. During the first moments everything runs ok. Though, in the middle of the process, the rocket starts to aim prograde, even with SAS on, pointing the aerodynamic part to the planet, screwing the braking which cause me to hardland and blow everything up. As you can see in the screenshots, I installed some wings in the rocket predicting unstable condictions during reentry due to the lenght of the last stage. However, I didnt expect it to be so tough and the wings to overheat during the process. I have already tried to not decouple and instead try to burn retrograde during the entry, but the engines tend to overheat. What do you people suggest me to try? Thanks for the help! SCREENSHOTS: (I don't know why, but the "Insert other media" isn't working.) http://imgur.com/Uf2VhLh http://imgur.com/CG83mem http://imgur.com/FoXZ4yN [Edited by Snark to provide inline images]

A quick demo of how to hit KSC every time in a spaceplane. When you hold the angle of the nose about 7 degrees above prograde, you get the best gliding angle and your impact point will steadily move downrange of the initially plotted ballistic arc. The further you point your nose away from "best glide", the less this effect till, at large angles, it actually causes the impact point to move closer. Whilst you can pitch down, left or right to acheive this effect, i recommend UP because it takes you away from the thicker atmosphere and gives you a respite from re-entry heat. As you can see, this mk1 doesn't have much problem with re-entry heat. Possible reasons for this 1. Inline cockpit is quite far back. The fly by wire unit has a pointy antenna thing on the nose, that moves the bow wave well forward of the cockpit. 2. large wing area means it stays high until it has lost a lot of speed. 3. engine pre-cooler makes a good radiator. As do the jet nozzles on the rapier. these parts surround the cockpit.

Hi, i have this SSTO that can go anywhere near Kerbin, but when i try to return and land, its almost impossible to control and land safely. As you can see, both CoM and Dry CoM are ahead of CoL, but upon reentry at some time the plane losses stability. Do you find what is wrong with the design? How could i solve it? Thanks And one more thing: The cockpit is always burning or almost at reentry, even having only heat setup at 70%

I have a lander on return from Mun. The game is saved on the final approach. There is not enough dV left to abort the landing. It's an aerobreaking maneuver directly from Munar ejection. Peri is 27km, I can bring that up to 32 or so. Apo before atmo is 8M or something like that. This is by far not the most aggressive aerobreaking I've ever done. I've flown this mission before, and came in on basically this return trajectory from Mun once before. I've taken this lander to minmus and come back home in a similar, more aggressive fashion. Two things are different this time: 1) I'm using a nose-mounted basic chute instead of a pair of radial mounted chutes. 2) This rocket inexplicably decided to become unstable during liftoff and lean towards 270 (it did not do this on prior launches). There are no additional asymmetries introduced, so I have no idea why that was other than, FNAR, the command capsule's reaction wheels toggled themselves off. (I discovered this after successfully wrestling the thing into orbit.) On re-entry, however, around 20km altitude, well before I ever let my hand NEAR the spacebar, the parachute is mysteriously 'destroyed by aero forces and/or heat.' At NO POINT does the part give me a heat bar. The housing for the parachute is still there, there is no explosion or anything, but the chute chamber vanishes. This has never happened to me before EXCEPT if I were to deploy the chute while the indicator was red (which it is). Why is my chute suddenly destroyed? The vehicle is just the pod, chute, and heat shield. SAS is off, the vehicle is stable and the heat shield is pointed in the right direction. I see no visual heat effect on the chute, nor is there any discoloration of the chute housing suggesting overheating is taking place. Valentina needs y'all's brains.

Problem 1. RSS & Realism Overhaul (at least FAR+ deadly reentry) installed - game version 1.0+ (tested in 1.1.3) 2. You got an airplane (anything landing horizontally) into low earth orbit 3. You want to get it back down without burning up. Usual outcome: Let's assume, you finally got a craft flying in FAR at both subsonic and high Mach speeds and even have thing not spinning out of control during reentry attempt. As soon as you try to reenter at LEO entry speeds (~8000m/s ish) stuff simply overheats and explodes :-( Howto do it anyway: a) Procedure: You can't use ablative heat shields, so you'll want a very shallow lifted reentry with as low an initial speed as possible, so the heat load can dissipate. You really need to fly the craft all the way down from orbit using a steep AoA to get a detached bow shock and limit overheating. 1. Get Apogee of your orbit to under 200 km above earth (propulsively or with very careful >100 km perigee atmospheric breaking if you dare) Otherwise your reentry speed will be too high and you will overheat before you even get enough lift to fly. 2. Get your perigee at 70 km or below (very shallow reentry) 3. Make sure the reentry shock front is detached. If your plane is pointy in flight direction (MK2 cockpit - good for supersonic performance on ascent but too pointy for nose first reentry) then you need to fly with high angle of attack to form the shock front on the bottom of your plane (20°-30° AoA or even more!) 4. At 80-90 km altitude you will start to get significant lift (at speeds exceeding Mach 20) keep pitched up to control vertical speed. Try to sink as slowly as possible, don't exceed 100 m/s vertical. 5. Keep flying with high AoA (blunt shockfront, high drag, lots of lift) and low vertical speed. If you can force a shallow climb, do it. It will bleed speed even faster. You will likely end up between 60km and 70km for seemingly ever. The reentry corridor might span 1/3 of a whole orbit from initial reentry until you are slow enough to fly circles or change direction. 6. Once you are below 3000 m/s you basically made it. You can trim down the AoA and descent more aggressively and maneuver around. b) Craft Design: 1. All "exposed" components should be able to sustain 2500K surface heating. WARNING: Most RCS thruster pods are not, might have to be placed in the back of the craft, above wings or similar to be shielded from reentry bowshock. Most engines also can't survive that much heat and need shielding from front and bottom (like the Shuttle's SSME) -- Hint: Small Landing gear pods can only sustain 1500 K, you'l likely need medium or large unless you reenter bottom up to shield them. 2. The plane must be aerodynamically stable at subsonic (for landing), supersonic, and hypersonic speeds in rarified atmosphere. You can test that with suborbital flights not exceeding 3000 m/s going up to 60-80 km. Many MK-2 fuselage planes tend to enter a flat-spin in thin upper atmosphere even though they are stable further down. I solved that with "SpaceShip 1" style tail-booms, with SR-71 style tail fins on them ... even though they aren't foldable, they gave me both enough tail stability and enough control authority for #3: 3. You need to find a way to trim the plane for extreme AoA flight aerodynamically, so you need quite a lot of control authority. If the airstream at Mach 20 wants to bring the nose down, you can't fight it with RCS for long. Even in this configuration the plane needs to be semi stable (stable enough that SAS can keep it from spinning out of control) - in a nutshell that means you need forgiving stall behaviour (since you basically reenter high-speed-stalled) Example: Flight with large AoA (22°) and level flight - at this point already descended to 65km and 6100 m/s: (At this point also my bow and mid section RCS thrusters had all but vaporised, only the three at the tail remained. FAR and deadly reentry have a habit of overriding your decision where to place RCS thrusters in a very convincing way ) This shuttle can sustain flight at +20° AoA thanks to setting of max control deflection (40°) and AoA setting -200 on the tail boom rudders. SAS is only used to keep roll and yaw centered. Tail rudder trim reset to zero AoA and 15° max deflection once speed below 2000 m/s, SAS no longer needed (self stable) In this flight I overshot my landing site by more than half a continent and ended up in the middle of the Indian ocean. I managed to ditch the craft with onlyminor damage (ripped one of the tail fins off, but the fuselage and wings held, Jeb was fine )

Okay - I'm finally getting to Eve and Jool, and I'm hitting a wall with aerocapture. I'm having ships simply explode. I've resorted to having ships just use lots of fuel, but that's making them large and unwieldy. Would be nice to have some ideas on how to best accomplish aerocapture, as well as good altitudes - is the KSP wiki still accurate on this? Thanks for any help you can give.

So when I activate the decoupler my command pod and science lab seperate but camera and control stays with Rocket engine and fuel tanks. This happened after I restored a quicksave. It has also happened in the past after I reverted to the launch pad. I am sure there is a simple fix (I hope) but not seeing any key commands that transfer controls from one unit while in flight. Please help and thank you.

I'm devoloping an Eve launcher from sea level, and while testing it on a Kerbin reentry, it always flips at 15,000 m aprox, and gets destroyed. It has 5 heat shields (1 big, 4 medium) and 4 AV-T1 Winglets. Also has 4 Advanced Inline Stabilizers. And it's perfectly symmetric. What I'm doing wrong? Here are two pics, one before the flip and other after: http://imgur.com/a/r0kJI Thank you very much for your answers!

So I was reentering a Minmus lander into Kerbin when I noticed the atmosphere seemed to be accelerating my craft. Note this was not a case of my speed increasing during descent due to gravity. The acceleration was much more significant than that. When I finally blew up at around 8 km altitude, I was on a Kerbin escape trajectory and going well over 4,000 m/s. The effect seemed to get worse the further down I fell into the atmo. Luckily I had a quicksave before reentering so I was able to try again several times, doing this and that differently, but still experiencing the issue. I even tried firing my engines retrograde but that actually seemed to make the problem worse (i.e. craft would speed up even more despite burning retro). Curiously enough, the problem seemed to fix itself by extending my landing gear (medium sized landing struts) before reentering, so I suspect this was some phantom force caused by the gear clipping slightly into the body of the lander (the “butt” of the lander to which the legs were attached was a Mk2-Mk1 adapter, which is slanted, so the legs had to clip slightly into it in order to deploy with the “feet” parallel to the ground; I don’t have a screenshot at the moment, sorry). Anyway, the problem was solved in this instance and I was able to land safely but I still wanted to post here in case others or I have this problem again (or in case someone wants to explore this as a Kraken Drive possibility!). Any input is greatly appreciated.

I have the feeling that managing the reentry heat is now much, much more difficult than it was in 1.0.5. In 1.0.5 I've been playing with a normal difficulty, for the 1.1 I've started a new career (because I *knew* there would be bugs, I wanted to see all the new stuff, and - just a very, very little - I hoped for the "barn-style" level 1 base), but this time with "moderate" difficulty. Where previously I would just make sure that I have enough parachutes, and I'm not diving down from the LKO at 90 deg angle, now I seem to need to consider adding a heat shield even for the Mk1 Command Pod, and really stress my fingers managing the ship orientation so none of the stuff attached to it (like that flat thermometer) burns in the atmosphere. I see that the difficulty setting for the heat is the same as it is for a "normal" difficulty game, so it should not matter. Is there so much changes in 1.1, is that some bug or imbalance, or my pilot skills got rusty sending yet another Kerbal with a rescue-to-a-rescue-of-a-rescue mission, and not really having time to bring them back?

HELLO! I am making a space shuttle. I pretty cool one in my opinion. I've spent a week working out on the stability. But for some reason it just wants to tick me off and flip out chaotically I've used the center of life and center of mass to make it stable. It is stable in normal flight, but when I come in from reentry, it loosed control. I am going to post a craft file so you guys can test if you want. Any advice with space shuttles and reentry will greatly help me. Also, the mods that I have that are with the ship is TAC life, and mech jeb, for the information. Stubborn Shuttle That will not cooperate craft file. Thanks a lot you guys!!

So, today, I made a Apollo-style Mun mission in Sandbox, just for fun. The mission went flawless but that's not the interesting part. On reentry, I noticed an orange temperature gauge pointing to the heat shield. Here's a pic of that: (sorry for the large size) I used KER to check wich part has critical temperature, and apparently, it was the heat shield This is just too funny. A heat shield overheating. Think about it. Oh, and apparently there's another heat shield floating in a eccentric solar orbit

Hello good Kerbal folk! I made a rather nice Mk2-based space shuttle in 1.1.2 (goo.gl/oP0Wt2). On Kerbin reentry the cockpit (Mk2 Standard) heats up way faster than anything else and explodes every time. I tested a shallow reentry profile with PE ~40km from a near-circular 87km orbit and it still cooks off at 33.5km (goo.gl/msjzfL). I'm using MechJeb just to keep AoA very close to zero for this test; my understanding is that an AoA of zero minimizes the stress on the craft (but does it minimize the heating?). After the cockpit explodes the centers of lift and mass are backwards, and the craft whips around violently, but it stays together and no other parts explode (I've run this test several times). You'd think that the cockpit - with poor Jeb and Bill inside - would be more resilient, or at least as resilient as the Mk2 storage and fuel parts, plus wings and landing gear etc. To me it's a bit unrealistic like this. Am I expecting too much of the Mk2 cockpit? Am I making an error I hadn't thought of? Or is there maybe a case to make the Mk2 cockpit a little less reentry-sensitive? Cheers, all. (goo.gl/c1LHLW)

I'm wondering what the best method is to return an SSTO safely given an orbit of 350 KM. You can alter the periapsis of the SSTO to 45 KM at once from the 350 KM orbit or you could alter the orbit to 75 km and then alter the periapsis to 45 KM. I have the impression that the second way is better. Is that nonsense or is that true? (If so, why?)

So, I'm back after a long hiatus and v1.0 and all that good stuff. I'm trying career mode and I am getting burned (pun intended) on the new aerodynamic and heat effects. I am trying to do a test contract for the RT-10 booster firing between 40km and 45km and a certain speed window, I did this by stacking three RT-10s with tweaked thrust limiters so the third one ignites while coasting in the target window. Contract satisfied, but then I can't get the capsule safely to splash down because the chutes keep failing. I've tried deploying them as early as possible but it seems like nothing I do will get them to open until 5km altitude and by the time my capsule + heatshield is that low, it's screaming along at nearly 1km/sec and the chutes tear right off. I'm not sure how to slow my capsule down enough to use the chutes safely without being able to deploy them earlier. Thoughts? Thanks!

Hi, so since 1.1 came out I decided to build a space shuttle mostly based on NASA's space shuttle. The whole thing launches great and it can get into orbit just fine, however problems arise when I go to reenter the atmosphere. Reentry goes smoothly til im about 20-15km in the air. At that point my shuttle spins out and begins to point engine first at the ground. Any ideas on why this might be happening? I've attached a picture of my shuttle's COM and COL with the ammount of fuel it has during reentry: I'd greatly appreciate any help, thank you!