No more SSTO's

[A_name]

Very impressive KerikBalm!

[Levelord]

I agree that the aero model for some reason doesn't take into consideration the overall layout of the wings. If the aero model can't see that I've made an aerodynamic shape/shell out of the wings on the ship then the aero model in itself is inherently unrealistic.

Then there's the weird issue where unless a part is connected to an attachment point, it will accumulate drag and overheat regardless of an ablative shield placed on top of it.

From what I'm currently seeing is that the new aero is somewhat an improvement over the old one, but SQUAD hasn't given us any new tools or parts that can handle it. As far as I'm concerned we are still using 0.9 parts that are not optimized to fly in 1.0 aero. None of the parts are able to deal with the new aero and this is comparing a Skylon airframe running RAPIER engines barely able to cruise 1000m/s in KSP with it's real life counterpart that can easily cruise at mach 5.5 (1,823m/s). Ive considered that perhaps this is a scaling thing with Kerbin being smaller, but it isn't the case. It's also likely that the engine pre-coolers does diddly squat at improving an engine's operating altitude (due to increasing heat at high altitudes) while the Skylon SABRE has an in built engine pre-cooler that works as intended.

All in all, I don't think SQUAD has given us the tools to build (at least practical) SSTOs. Building real life counterparts of SSTOs doesn't seem to work and I still have weird fantastical designs fly in the new aero, so it is still hardly that much realistic even though people claim it is. It's a step in the right direction though, but I think it still needs a lot of work.

[Aanker]

If the aero model can't see that I've made an aerodynamic shape/shell out of the wings on the ship then the aero model in itself is inherently unrealistic.

Exactly what I'm going for. Currently (and ironically) my most aerodynamic looking designs are also the most useless. As broken as the previous aero physics were (and no, I wouldn't want to go back to that), they did allow the builder to shape into being spaceplanes that looked as if they could fly in real life, as opposed to large flying oil drilling rigs.

[Wanderfound]

As before, if you want your aero to be realistic-ish, you need FAR. In particular see http://forum.kerbalspaceprogram.com/threads/20451-0-90-Ferram-Aerospace-Research-v0-14-7-4-2-15?p=1870281&viewfull=1#post1870281 for what's planned in the new version.

NuStock Aero is no longer dreadful, but it's still nowhere near an accurate simulation.

[musicpenguin]

Can't do it? Try harder.

Although I agree it is much harder since 1.0.

[LordFjord]

Indeed, it is much harder. Managed to get my first 1.0 SSTO into orbit. It was close but it got up there. The journey down again - well, that was a mess.

Javascript is disabled. View full album

[EnDSchultz]

It sure IS possible. I've managed with Tech 5 parts. It's ugly, heavy, overbuilt, carries no payload whatsoever and it pretty much requires a perfect ascent profile... but it goes up and can even come down again if you're super careful and employ airbrakes copiously:

[ak8]

This is my new SSTO design. It carry so much useless weight for beautifying, so it can only do a round-trip to LKO.

We cannot depend the overpowered jet engines in 0.9 anymore. Bring more oxidizer is very important now.

Javascript is disabled. View full album

Btw, I love the new fuel tank. It look like fighters' drop tanks.

[stardog573]

SSTOs are not dead, they are actually more useful than ever. In previous versions, we spent a lot of time for ascending and gaining speed at high altitude but now it's just one shot and really practical to use.

I uploaded my tutorial on youtube. Takeoff, getting into orbit with cargo, reentry and landing - all without problem.

[KerikBalm]

This is my new SSTO design. It carry so much useless weight for beautifying, so it can only do a round-trip to LKO.

We cannot depend the overpowered jet engines in 0.9 anymore. Bring more oxidizer is very important now.

Actually, I think the jet engines are still OP'd (I'm saying that as the one posting a design with a 41% payload fraction to a 79x79 km orbit, and I think I can improve upon that by a few percent).

The TWR on the Rapers is ridonculous... basically, I'm finding if your design can break mach 1, then it can get to 1,300 m/s (on Rapiers, lower on turboramjets), which means it can get to orbit with only about 1,100 m/s in tanks for the rockets. A rocket that only needs 1,100 vacuum dV can have a pretty darn good payload fraction.

Its not as ridiculous as before... but its close...

BTW, somehow I think having a large payload helps... that monster I posted on the last page was actually the fastest spaceplane I managed to make (or rather, it got the fastest on jet power), despite not being able to accelerate past mach 1 in a climb/level flight (a dive was needed to get past mach 1, and into the good part of the engine/s power curve)... normally my planes would fry up at that point... but I think it was so large, with so much payload acting as a heat sink, that it didn't overheat because of that.

It clearly had absorbed a lot of heat, because OX-stats in the utility bay behind the cockpit started cooking off when coasting at 64 km prior to the final orbital insertion burn.

So the parts had to be pretty darn hot to be able to transfer enough heat to adjacent parts, into the utlity bay, through 3 large reaction wheels, and onto the ox-stats on those reaction wheels.

I attribute its survival at those speeds to a large heat-sink.

[qromodynmc]

I think sstos are more realistic than they were in 0.90.

I mean look at to real life,Who stays in the atmosphere to get enough speed?

My recommendation; instead of jets,use rockets more,build bigger planes.

[White Owl]

My initial experiments suggest that 75 m/s equivalent airspeed is the magic number for reliably surviving reentry. Faster than 75 m/s EAS and you risk exploding various internal bits, like batteries. So the trick to designing a spaceplane that can reenter safely is to give it enough lift and pitch authority to maintain altitude at that airspeed. Realistically, it should glide a good deal slower if you want some margin of error.

I'm having trouble getting an authentic-ish looking space shuttle to glide and maintain altitude that slow. Needs further research. But more conventional airplane shapes with more wing shouldn't have any problem with reentry so long as you know what EAS to aim for.

[iVG]

I've found out that airbrakes do pretty good job as attitude control surfaces in the higher atmosphere. Check the one in my signature. I took my time to put a decent ascent/decent profile description for those struggling with spaceplanes.

[Siltuz]

I don't know why anyone has a problem with the new SSTO's... Sure they are less fuel efficient than before but it is still fairly simple to make them (bearing in mind my first 0.9 SSTO was a week before 1.0), but on career I have just unlocked mk2 parts and made an SSTO that reaches 150k orbit and back fine, and I am not a good pilot yet in this version, so it should be easier with better parts right? I was also constrained by the 30part limit so I couldn't take as much fuel as I would like. I think SSTO's are still perfect for getting small satellites into orbit, and maybe with some refueling they can be more.

[WhirlwindMonk]

For a thread claiming that SSTOs are no more, it sure has inspired me to try to make some of my own. I'm also encouraged by the people saying they had trouble pre-1.0 but can do it now, since I've always been terrible at planes in general and don't think I have ever managed to successfully take a spaceplane to orbit. Just need to spam a few Minimum missions now to unlock enough of the tech tree.

[regex]

I don't know why anyone has a problem with the new SSTO's...

Because they've been reigned in by the new aerodynamics. People are now faced with a taste, however small, of why we humans have never built an SSTO that takes off from a runway. New ascent profiles require much more rocket fuel than before, meaning the craft have to change shape.

People don't like change, especially when the change results in a tougher time getting what they want. Pre-1.0 you could build purely for aesthetics and do silly things like stack tens of wings. Now you have to at least try for an aerodynamic shape. Is it perfect? No. Go talk to ferram4 about compromises in oldFAR for the purpose of trying to figure out the shape of whatever crazy contraption the user made because KSP let them. KSP uses some of those same techniques, as I understand it. And if you're still mad about it, check out nuFAR, which voxelizes the vessel into a single shape. Then you'll get a real taste of "limited creativity"; KSP is at least kind enough to treat your wing shape differently based on speed, which gives you much more leeway in design.

[Siltuz]

Because they've been reigned in by the new aerodynamics...

Wasn't there a whole uproar just before release about mining and how it would make the game too easy? So, it seems like squad have the impossible task on their hand of people being outraged by both a challenge and a perceived lack of challenge simultaniously! There's no winning really

[etheoma]

Basically things got more realistic. If SSTOs were as easy IRL as they were pre-1.0 we'd probably have a Mars colony by now.

Try igniting your rockets lower in the atmosphere.

ERRR... no non plane SSTO's are unrealistic because you would need a ultra high ISP thrusting method which also provides enough thrust. Also jet engines can't deliver enough thrust at even medium altitudes to lift a rocket.

And considering the RAPIER engine is basically a SABRE Engine yes you should be able to relatively easily get up a payload or low kerbin orbit. And how the new heating works is super stupid, Oh look I can go 800m/s at 1km with an unshielded vessel but at 18 - 20km where there is less than 1/4 the air I can only go 900 - 1000ms with an unshielded vessel.

That makes absolutely no sense 1/4 the air mean roughly 1/4 the shock heating because there is 1/4 the air bombarding your ship at any given speed.

And no my problem isn't the trust of the engines its about the scaling of the shock heating which is extremely arbitrary.

And I'm someone who uses FAR and Deadly Reentry so I don't have a problem with a challenge but I have a problem with arbitrary mechanics which make no sense.

Edited April 30, 2015 by etheoma

[WafflesToo]

The only thing that surprises me is that there aren't more posts like this one, everyone (who wasn't already flying FAR) just got too comfortable with the broken flight model. I guess the pixie-dust powered blimps just aren't going to work anymore

...And if you're still mad about it, check out nuFAR, which voxelizes the vessel into a single shape...

This does intrigue me, I'll have to go check that out later.

[etheoma]

The only thing that surprises me is that there aren't more posts like this one, everyone (who wasn't already flying FAR) just got too comfortable with the broken flight model. I guess the pixie-dust powered blimps just aren't going to work anymore

This does intrigue me, I'll have to go check that out later.

I flew with FAR and Deadly Reentry, the Aerodynamic are not terrible but the heating is stupid, and I'm comparing that with Deadly Reentry, the stock heating is extremely arbitrary when your trying to make a plane SSTO.

I was like Oh I'm getting destroyed by shock heating at 12km at 900ms ok lets go up to 22km Oh no I only gained another 100 maybe 200ms before my ship explodes even though there is MUCH less air at 22km.

Edited April 30, 2015 by etheoma

[Radam]

Even before 1.0, my sstos had a cargo fraction of about 30% and were cutting their air engines at about 1300ms. Same is here...

[panzer1b]

SSTOs are still going to be a major part of the game, but i feel the whole SSTLaB (single stage to laythe and back) are mostly dead (without abusing exploits).

The MAIN reason SSTOs were so attractive back in the day is that you could get rather great payload fractions into orbit without dumping a single part (nice during career), and that jets were in general overpowered and could get you to a 400km AP suborbital trajectory ALONE! They also have a appearance factor, certain people (such as myself) find aircraft like things much more pleasing to look at then giant cylinders with a nose cone atop. The last one is a personal preference but the 1st 2, especially how overpowered and overly efficient jet engines were (i could SSTO a 12t craft to laythe and bakc using 150 LF ONLY), made them very very popular, and it wasnt exactly difficult to make one fly provided you had the CoG and CoL properly alligned, that was the only real requirement for SSTOing.

Now, you get a MUCH tougher engineering challenge, rapiers die completely around 30km, and above that it is just IMPOSSIBLE to use them in jet mode. The other 2 jet engines are inferior to the rapiers for high altitude and speed so im not even gonna talk about those. Point is, that to get a SSTO to orbit, you need WAY more fuel, and you also actually need some dedicated space engines too, which arent exactly very fuel efficient unless you stuck ions into the thing (and somehow have enough TWR to get yourself up to 2000m/s before dropping back down). This usually means that you simply do not have enough fuel to go interplanetary on just rapiers+whatever rocket engines you chose to use (even the nuke).

SSTOs are far from dead, but i actually believe that 100% legit non-exploity SSTOs to other planets for the most part are done. There is no way to get large enough fuel quantities up there, and with the nerfs to every single rocket engine ISP wise, and ions only being feaseable through exploits (such as what i did when i crammed 15 ion engines and 27 xenon fuel tanks and 300 massless batteries all into a service bay 1.25m). I just dont see hwo you are going to make a SSTO to the farther reaches of space 100% legit.

[Exclipse]

My only problem with SSTOs right now is how broken the heating system is right now. Aside from how unpredictable it already is, I finally managed to get my SSTO to orbit and then it just randomly exploded, I am guessing due to some stupid heat calculations.

It makes not sense that I can reenter just about any craft going 2000m/s + without shielding, but when I try to take off and go kerbin to space going 900m/s everything explodes.

[Blaster]

I spent a whole evening on this, and I already namaged LKO and reentry without explosion.

Tips: One Ram-Air Intake per Engine

Multiple intakes impart far more drag than they provide extra air.

Use AIRBRAKES during reentry to prevent burning up.

Learn to ascent profile. Bad ascent meaans no gas left in orbit.

[TK421d]

Because sacrificing fun for realism is not always a good thing.

i have the opposite experience as you,

1) i hate spaceplanes and have 99% exclusively built rockets.

2) the new aero is death for rockets, its like balancing a bowling ball atop a baseball bat, all supported on your finger by a needle.

the "realism" for rockets has 100% dissapeared with the new aero. so planes may be more fun for you, but i am having very little fun at the moment.