SSTOs! Post your pictures here~

[Rune]

6 hours ago, Angel-125 said:

This might explain a few things. I've always been lousy at spaceplane design, and gave up on it entirely until this evening. The Mk2 designs I come up with just don't have the oomph to reach orbit, and I'm about ready to go back to flying rockets. I'll have to give this a try though. Also, if you know of a good SSTO tutorial for KSP 1.2, I'm all ears.

Actually, SSTOing in 1.2 is so easy once you know a couple of rules, I'm pretty sure I can cover anything important in a single post:

The key is to hit the right TWR and drag. Once you do that, the ascent profile is as easy as going in a straight line and switching the RAPIERs to closed cycle when appropriate! Basically, you go flat-ish at sea level until the RAPIERs hit the magic 400m/s (the point when their thrust curve gets to its sweet spot, and the RAPIERs continue increasing thrust as you climb), then just watch as your vertical speed increases as the planet curves down under you and you keep going in your straight line, until the air is thin enough that the RAPIERs start giving out. Can't be any simpler! You just have to make sure that your ship is able to hit those magic 400m/s at level flight at sea level, and the rest will take care of itself. And I seriously mean that, I need many more manual control inputs when grav-turning a rocket, than flying a SSTO to orbit, where I just have to take off and set the initial "climb".

Since rocketry is all about ratios, here are a few for you: the optimum TWR at takeoff should be around 0.5-0.7. About 33% of your takeoff mass must be fuel (at least), and I usually budget about 400-500 LF units for the airbreathing climb, per RAPIER, with the rest being LFO mix. I only use RAPIERs, of course (they are the best by far, so why use anything else). And always remember that your upper limit of payload to LKO is up to ~50%, but 25% is much more doable with some aesthetics flair, or inefficiencies, or just plain margin. Small or big your design might be, those ratios will hold, so make sure to check the final numbers in your design, make a few divisions and multiplications if need be, and change things accordingly. You can't cheat physics! (I mean, you can, but it is cheating, and it's done with the cheat menu )

And the other half of the equation are aerodynamics. This is more of a "how the game engine likes things" kind of thing, in order to be able to hit those 400m/s, with a TWR as low as 0.4 (but normally a bit more), to have that nice >25% payload ratio. But some simple rules will help a lot:

-Leave no open nodes. Front or back, that's important: no matter how it looks, if you have an open node somewhere, the game thinks that is a flat surface against the wind. The drag will be horrible.

-Also avoid unshielded surface-mounted stuff. These days, it pays to put everything inside cargo bays and/or fairings. You can check if a part is being shielded or not (and how much drag it gives) with the debug menu, by enabling the aerodynamic values to be displayed int he right-click menu. The arrow visualization tool is crappy, and will mislead you. This will teach you a lot, if you use it.

-Use just the intakes you need. Frontal surface is the main thing that will limit your drag, having more intakes than absolutely necessary will increase your drag without giving anything in return. One shock cone per two RAPIERs, or a single precooler per RAPIER, is more than enough. Yeah, the ideal designs usually turn out very, very long and skinny that way. That is why we end up going to Mk3, for the added diameter with the same frontal surface (after a few adapters).

-Mk2 fuselages are crappy. If you want to build Mk2, make sure your TWR is above 0.6, and that will hit your maximum payload, since you still have to be >25% fuel at takeoff, and you need proportionately more engine weight. The best drag/tankage ratios are the rocket parts, with Mk3 a close second. But Mk2 is still perfectly doable, of course, just with a lower payload fraction.

-Wings are necessary for flight, but dead weight in the climb to orbit. Less is more, but you have to have enough to take off when full and get to that level speed run at sea level. BigS wings are cool, because they double as LF reservoirs, and thus their mass hit is smaller (even though as fuel tank only, they are rather crappy).

 

Rune. Yup, that's pretty much it, the rest is just making it stable and capable of taking off, but that's airplane-building.

Edited April 20, 2017 by Rune

[Laughing Man]

5 minutes ago, Rune said:

-Mk2 fuselages are crappy. If you want to build Mk2, make sure your TWR is above 0.6, and that will hit your maximum payload, since you still have to be >25% fuel at takeoff, and you need proportionately more engine weight. The best drag/tankage ratios are the rocket parts, with Mk3 a close second. But Mk2 is still perfectly doable, of course, just with a lower payload fraction.

Why are they crappy? Do you mean in terms of the amount of fuel they hold relative to size? They do provide a bit of body lift too if I'm not mistaken.

[Rune]

12 minutes ago, Laughing Man said:

Why are they crappy? Do you mean in terms of the amount of fuel they hold relative to size? They do provide a bit of body lift too if I'm not mistaken.

As I said in the post @Angel-125 quoted, not only do they have one of the worst tankage ratios in the game (full weight/empty weight), they have horrible drag values. The short Mk1-Mk2 adapter, in particular, is murder. It has around... ¿four times? ¿more? Can't remember off the top of my head, but something horrendous... anyhow, several times the amount of drag of a similarly-sized Mk1 tank. And their lift values are nothing to write home about.

 

Rune. Check the thing I said about aerodynamic data in context menus, it's very informative.

Edited April 20, 2017 by Rune

[Tyr Anasazi]

39 minutes ago, Rune said:

Actually, SSTOing in 1.2 is so easy once you know a couple of rules, I'm pretty sure I can cover anything important in a single post:

The key is to hit the right TWR and drag. Once you do that, the ascent profile is as easy as going in a straight line and switching the RAPIERs to closed cycle when appropriate! Basically, you go flat-ish at sea level until the RAPIERs hit the magic 400m/s (the point when their thrust curve gets to its sweet spot, and the RAPIERs continue increasing thrust as you climb), then just watch as your vertical speed increases as the planet curves down under you and you keep going in your straight line, until the air is thin enough that the RAPIERs start giving out. Can't be any simpler! You just have to make sure that your ship is able to hit those magic 400m/s at level flight at sea level, and the rest will take care of itself. And I seriously mean that, I need many more manual control inputs when grav-turning a rocket, than flying a SSTO to orbit, where I just have to take off and set the initial "climb".

Since rocketry is all about ratios, here are a few for you: the optimum TWR at takeoff should be around 0.5-0.7. About 33% of your takeoff mass must be fuel (at least), and I usually budget about 400-500 LF units for the airbreathing climb, per RAPIER, with the rest being LFO mix. I only use RAPIERs, of course (they are the best by far, so why use anything else). And always remember that your upper limit of payload to LKO is up to ~50%, but 25% is much more doable with some aesthetics flair, or inefficiencies, or just plain margin. Small or big your design might be, those ratios will hold, so make sure to check the final numbers in your design, make a few divisions and multiplications if need be, and change things accordingly. You can't cheat physics! (I mean, you can, but it is cheating, and it's done with the cheat menu )

And the other half of the equation are aerodynamics. This is more of a "how the game engine likes things" kind of thing, in order to be able to hit those 400m/s, with a TWR as low as 0.4 (but normally a bit more), to have that nice >25% payload ratio. But some simple rules will help a lot:

-Leave no open nodes. Front or back, that's important: no matter how it looks, if you have an open node somewhere, the game thinks that is a flat surface against the wind. The drag will be horrible.

-Also avoid unshielded surface-mounted stuff. These days, it pays to put everything inside cargo bays and/or fairings. You can check if a part is being shielded or not (and how much drag it gives) with the debug menu, by enabling the aerodynamic values to be displayed int he right-click menu. The arrow visualization tool is crappy, and will mislead you. This will teach you a lot, if you use it.

-Use just the intakes you need. Frontal surface is the main thing that will limit your drag, having more intakes than absolutely necessary will increase your drag without giving anything in return. One shock cone per two RAPIERs, or a single precooler per RAPIER, is more than enough. Yeah, the ideal designs usually turn out very, very long and skinny that way. That is why we end up going to Mk3, for the added diameter with the same frontal surface (after a few adapters).

-Mk2 fuselages are crappy. If you want to build Mk2, make sure your TWR is above 0.6, and that will hit your maximum payload, since you still have to be >25% fuel at takeoff, and you need proportionately more engine weight. The best drag/tankage ratios are the rocket parts, with Mk3 a close second. But Mk2 is still perfectly doable, of course, just with a lower payload fraction.

-Wings are necessary for flight, but dead weight in the climb to orbit. Less is more, but you have to have enough to take off when full and get to that level speed run at sea level. BigS wings are cool, because they double as LF reservoirs, and thus their mass hit is smaller (even though as fuel tank only, they are rather crappy).

 

Rune. Yup, that's pretty much it, the rest is just making it stable and capable of taking off, but that's airplane-building.

Excellent summary, thanks

[Angelo Kerman]

3 hours ago, Rune said:

Actually, SSTOing in 1.2 is so easy once you know a couple of rules, I'm pretty sure I can cover anything important in a single post:

Rune. Yup, that's pretty much it, the rest is just making it stable and capable of taking off, but that's airplane-building.

This really helps, thanks! I will definitely bookmark your post and see what I come up with. I also didn't realize that open nodes slows down your craft! Gives me an idea for Wild Blue Tools...

Thanks again for your help!

[Rune]

2 hours ago, Angel-125 said:

This really helps, thanks! I will definitely bookmark your post and see what I come up with. I also didn't realize that open nodes slows down your craft! Gives me an idea for Wild Blue Tools...

Thanks again for your help!

You are welcome! I had a feeling it was something like the node thing that was thwarting your efforts. One of those non-intuitive KSP things where it's not how you see it, it's how the aerodynamics model sees it.

 

Rune. Always glad to be of help.

[UnidentifiedObject]

 

"SLIGHT" SSTO

 

 

 

 

PARTS

250

 

MODIFICATIONS

E4 P-Wing Texture switch v0.2
E4 P-Glass v0.1
ProceduralWings
TweakScale

Edited April 20, 2017 by UnidentifiedObject

[System Error Message]

a lot of what you guys say about building SSTOs arent true. I built a massive SSTO that isnt really efficient in the first place in terms of aerodynamics, has unbalanced thrust so it will spin without SAS and you need to use the RCS just to keep the heading on full thrust. The thrust to weight ratio also isnt good either. If you're wondering why i built such a thing, well i believe that if you want to make a massive spaceship that can land anywhere it must be able to land and take off anywhere without needing a launch pad, hence the use of a run way and single stage not to mention it uses liquid fuel engines from ground to space than the nuclear engines to orbit kerbin, only 2 thirds of the weight is fuel.

There are a few very simple rules really to building SSTOs efficiently and a lot of it is less to do about aerodynamics, more to do about rockets and structural. First i picked the most efficient part for fuel/weight. You have the weight of the fuel which is constant, and the weight of the body. The mk2 body is not the most efficient fuel to weight but offers some lift which is useful but not as the main body. I just think of them as wings with fuel or that has better structure than wings alone. 2nd is to pick an engine with the best fuel to weight ratio but you have to consider the engine you use in the atmosphere and space. This means you have 2 or 3 sets of engines. You'll want engines that are the best in the atmosphere for take off (thrust/fuel and thrust/weight). If you use jets you must take into account the fact that jet engines require intakes and engine precooler (extra weight to factor in), engines with the best thrust/weight to go between atmosphere and space, and the most efficient engines for use in space (ideally, as it would take too many ion engines to push my massive SSTO in space).

If you carry a convert-a-tron 250 you may want to factor in ore's potential fuel per tonne ratio as well.

make your craft structurally sound. Clippings will cause it to move about meaning you lose energy to friction or other weird glitch causing forces. Shakes and things that are loose will only slow you down so make more use of struts as sometimes you may need multiple struts per part.

Bias your RCS for lit in an unbalanced thrust. If like my massive ship your thrust is off COM you can use RCS to help stabilise and lift your craft up. It may seem insignificant but it can help gain some meters of orbital altitude while you're thrusting forwards (usually between a few to 100 meters but you dont want to lose altitude though). So just place some RCs on one side of the craft, and more on the other side.

Aerodynamics dont matter, speed is king. If you can gain a significant speed at launch and just go near vertical you will have spent less fuel on the most expensive part of the journey. The more velocity you gain early on the more fuel you save despite drag (this is with liquid fuel engines from take off) as gravity is more significant than drag so getting less gravity early on means less fuel wasted. On my massive SSTO that uses liquid fuel engines from take off i pitch up to 80 degrees right after take off and after 10KM altitude i start to pitch down slowly very much like what a space shuttle does.

 

My massive SSTO is on the previous page, It defies the way people usually design SSTOs. It does take a while to get to orbit though.

[TedwinKnockman66]

5 hours ago, UnidentifiedObject said:

 

"SLIGHT" SSTO

 

 

 

 

PARTS

250

 

MODIFICATIONS

E4 P-Wing Texture switch v0.2
E4 P-Glass v0.1
ProceduralWings
TweakScale

If this custom made cockpit, how you did him without annoying helmet?

[Wanderfound]

https://www.dropbox.com/s/eqreh7jzae53mln/Minmus Panther D.craft?dl=0

[steve_v]

From the one short-lived period where I didn't have FAR installed, and therefore probably the only one suitable for this thread:

Only ~300m/s in LKO, but it was designed for Laythe, so as long as it makes orbit...

My current (modded) workhorse is a little bigger:

This thing began life as a quick muck-around with M2X/M3X parts, and despite being both ugly and inefficient, it's capable of lifting anything that fits in the cargo bay - even when flown by a drunk chimpanzee. As such, it's somehow remained in service.
4KM/s + in LKO probably helps too. There's life support stuff and an inline clamp-o-tron hidden in the mk3 service bay up front.

[Laughing Man]

On 20/04/2017 at 1:18 PM, Rune said:

As I said in the post @Angel-125 quoted, not only do they have one of the worst tankage ratios in the game (full weight/empty weight), they have horrible drag values. The short Mk1-Mk2 adapter, in particular, is murder. It has around... ¿four times? ¿more? Can't remember off the top of my head, but something horrendous... anyhow, several times the amount of drag of a similarly-sized Mk1 tank. And their lift values are nothing to write home about.

 

Rune. Check the thing I said about aerodynamic data in context menus, it's very informative.

Hmm, this makes me feel a lot better about my Mk.2 spaceplane's performance! I'll check out context menus as suggested.

Oh and they may be crappy, but the Rule of Cool must always come first!

EDIT: Just checked the Mk2 parts relative to the Mk1 parts on my plane. Holy excrement that drag! Query:- do you avoid Mk2 parts specifically because of this issue? I'd still like to use them where possible.

Edited April 22, 2017 by Laughing Man

[Aerospacer]

Some old stuff - november's design.

Singlepantheric career ssto (tech lvl=sc160) Pantherinity-2A, dV on LKO = 2077 m/s.

Was made for max dV and flight to... see below.

 

Edited April 22, 2017 by Aerospacer
typo

[TeeGee]

Tested: 44 tons to LKO with over 1,000 m/s delta v remaining.

Tested: 120 tons to LKO with ~1,000 m/s delta v remaining.

 

Edited April 22, 2017 by TeeGee

[Wanderfound]

Craft file at https://www.dropbox.com/s/mkniu3tnpnzd9qc/Kerbodyne Pathfinder.craft?dl=0

[VICTORBILL]

Duna SSTO Refueling

Duna and back without nuclear engine.

► Album

► Specifications:

Parts: 94

Mass:164.5t	Width: 20.5m
Height: 6.4m	Length:26.1m

► Craft:

Duna SSTO Refueling

► Video:

youtube.com/c/victorbill

 Thanks for viewing

 

Edited April 23, 2017 by VICTORBILL

[Numerlor]

It's not much but the wheels are nice addition to it (see spoiler). To take off you need to be going around 100m/s or kraken will attack. Craft file
It is also pretty easy to handle at normal flying but lacks speed

 

Spoiler

 

Edited April 23, 2017 by Numerlor

[AeroGav]

On 23/04/2017 at 10:21 PM, Numerlor said:

It's not much but the wheels are nice addition to it (see spoiler). To take off you need to be going around 100m/s or kraken will attack

  Hide contents

 

That's awesome.   I usually smash up the facilities on the way back,   but you'd found a way to do it on departure !

 

[Tyr Anasazi]

I want to thank Stratzenblitz75 for his amazing videos, which gave me inspiration to install mods which have made my KSP experience a hundred times better than before!

My original design for an SSTO spaceplane has matured and I feel it's ready to share now. Craft file uploaded.

Amadeus is a 100% Stock, easy to fly, stable and reliable heavy lifter. My flight testing hasn't gone beyond LKO but my guess is it can go quite a bit further. Having the cargo on the outside rather than in a bay means that within the constraints of TWR and drag, your imagination is the limit.

Wait till you see what Rocco can do (coming soon). Here is the video of the flight of Amadeus, enjoy:
 

 

Get the AMADEUS craft file here

The link includes Action Group info, flight profile info and more.

Edited April 26, 2017 by Tyr Anasazi

[hurdurdur]

This bird is dead easy to fly (initial takeoff to 10km can be done at 50 degree angle, in orbit there is still lots of fuel left, big wing area makes aerobraking easy), seats 5. Pretty good for taking 5 kerbals to space stations etc.

[mystik]

On 4/20/2017 at 2:58 PM, Rune said:

And the other half of the equation are aerodynamics. This is more of a "how the game engine likes things" kind of thing, in order to be able to hit those 400m/s, with a TWR as low as 0.4 (but normally a bit more), to have that nice >25% payload ratio.

This is good for local SSTO, but if you want to go build a SSTA you cannot use RAPIERS as they are a lot of weight to carry around. I found that a ship can go to space using a combination of RAPIERS and a single Vector engine. My ship is about 300t and I can fly it with 6 rapiers and 1 Vector. It can successfully land on Tylo. Tested. It can reach Moho. It is part of a two stage ship. The lander (which is a space plane) and a space tug, that it docks to and travels to places.

It could not do the distance with rapiers alone. They are heavy and not that efficient if you want to go far. So, I kept them to a minimum, then burn the Vector until it reaches 400m/s then shut it down and so I get past the 400m/s barrier without needing to use all exclusive rapier setup. The reason why my ship uses no nukes is that you cannot rely on nukes to land on Tylo. It just does not work. The tug uses nukes because it only needs to land on low gravity objects to refuel, but the real workhorse is the lander spaceplane, and the hardest place to land on is Tylo. It is very stressful to not overdo it and get the landing right with only a few hundred m/s left before touchdown.

I have been lazy recently but I am looking to post my ship and thus enable full exploration of the KSP solar system. Rapiers are great for local travel. Long distance they kinda add weight and reduce the DV you can store without ending up with a gigantic ship. I have made a SSTO that weighs very little with one rapier and it works. But as you can tell, it is for one crew transfer to the space station and back, or for returning astronauts from rescue missions.

Edited April 27, 2017 by mystik

[Rune]

2 hours ago, mystik said:

This is good for local SSTO, but if you want to go build a SSTA you cannot use RAPIERS as they are a lot of weight to carry around. I found that a ship can go to space using a combination of RAPIERS and a single Vector engine. My ship is about 300t and I can fly it with 6 rapiers and 1 Vector. It can successfully land on Tylo. Tested. It can reach Moho. It is part of a two stage ship. The lander (which is a space plane) and a space tug, that it docks to and travels to places.

It could not do the distance with rapiers alone. They are heavy and not that efficient if you want to go far. So, I kept them to a minimum, then burn the Vector until it reaches 400m/s then shut it down and so I get past the 400m/s barrier without needing to use all exclusive rapier setup. The reason why my ship uses no nukes is that you cannot rely on nukes to land on Tylo. It just does not work. The tug uses nukes because it only needs to land on low gravity objects to refuel, but the real workhorse is the lander spaceplane, and the hardest place to land on is Tylo. It is very stressful to not overdo it and get the landing right with only a few hundred m/s left before touchdown.

I have been lazy recently but I am looking to post my ship and thus enable full exploration of the KSP solar system. Rapiers are great for local travel. Long distance they kinda add weight and reduce the DV you can store without ending up with a gigantic ship. I have made a SSTO that weighs very little with one rapier and it works. But as you can tell, it is for one crew transfer to the space station and back, or for returning astronauts from rescue missions.

A lot of people bring this up when I talk about the RAPIER being the only sensible solution for SSTO... and it's completely irrelevant. We are talking about Single Stage To Orbit. Not Tylo, not Layhte, not Minmus, and not Duna. Obviously the RAPIER is not the best engine for in-space travel. The nukes are. So count your nuke as part of the payload fraction of your mostly-rapier-powered plane-thing, and you have yourself the longest-range single stages in the game (I am intentionally ignoring ions, because that is not the point I'm making).

And if we are talking about SSTAnywhere and Vectors... well, I have this. No intakes.

 

Rune. And I have an even better one without wings. But that's untested.

Edited April 27, 2017 by Rune

[Joseph Kerman]

This is actually the first orbital return test of the craft, so the autostrut on the T-tail and the landing photos (I crashed it in a hill side, then a desert dune) are missing.

[Soda Popinski]

I took some advice, and moved the cockpit back...way back.  This is the Bonnie Ship The Diamond.  What you're seeing is a fully automated (kOS) take-off.  It can also do a fully automated de-orbit and landing (twice so far), landing...runway adjacent.  I'll post that when I get good light on its next mission.  Part of my inspiration was to make an SSTO that doesn't look like an SR-71, like most of my SSTOs.  Someone pointed out, instead it looks like a Skylon.

Edit: I think I need to work on the automated EDL, or at least check my fuel balance better.  This was the first "real mission" for The Bonnie Ship The Diamond.  The 2 previous successful landings were launch to orbit and de-orbit tests.  This time, I captured a capsule to re-use as a re-entry pod, and "rescued" and object for a contract.  I also had a tourist in the cockpit, and ferried down Bill and Bob from my space station.

 

Edited May 3, 2017 by Vanamonde
Weird blank spaces removed.

[Numerlor]

I'm finally sahring my first Mk3 SSTO that is also Mun capable, much can be improved on it as suggested by AeroGav but hell, who cares.

During reentry it can recover from pretty bad spin and has high AoA ( I managed to keep pointing at 65° vector without flipping at 20000m after that I flipped because I forgot to stabilize it) 
Landing should be done back wheels first, ofcourse. On my first inteact landing on Mun it had excess oxidizer so use raipers more or remove around 1k of oxodizer

Craftfile download

Edited April 27, 2017 by Numerlor