SSTOs! Post your pictures here~

[Jens Lyn IV]

31 minutes ago, Rune said:

If you put them in negative control values, they will work as intended flying tail-first.

But I'd still have to do it manually, and I'd rather keep my attention where it's needed. Airbreathers respond very sluggishly to throttle changes, and that can quickly get "interesting" when hovering...

[AeroGav]

Hmm,  how strictly is the SSTO rule applied in here?  I like building stageable boosters onto my spaceplanes, because you can get extra delta V and let's face it, decoupling is fun !  But it disqualifies my designs from a lot of threads, even though the re-usability factor is way, way higher than the space shuttle. I did put a lot of time into this 150 wing part beast,  it's a shame not to share it.    

https://kerbalx.com/AeroGav/Kerboliner-Stretch-36-Super

This is it taking off from Duna, Ike in the background.

Top profile over Kerbin.    Two passenger cabins give a total crew capacity of 36 Kerbals.  It has ISRU.     The resident engines are 3 NERVs and 2 RAPIER.   Not a lot to be pushing all that !   So, we have a Whiplash booster that couples to the centreline NERV, and two Terriers on the wingtips.   That's about 3000 cost worth of engine being thrown away, in return for giving 36 Kerbals a ticket to just about anywhere.    Launch mass is 110 Tons,  even with the Whiplash cooking TWR is only 0.3.  

It does fly a lot more like real aircraft.  Pull it off the runway too soon, it'll fly around for a bit but constantly loose speed and eventually flop back onto the deck.   You have to pay attention to angle of attack to accelerate.  On the other hand, it's very stable, which helps with precise control. When shooting for orbit, I control the vertical by making pitch trim adjustments on the keyboard to get the most efficient AoA,  and make occasional roll corrections with Q and E.   After circularising in LKO, it had around 3300 LF.     Boosting our AP to Minmus takes about half that, so this is probably good for a straight shot at Duna if you want to go direct.

It can take off from Duna and Laythe without these boosters however, due to the reduced gravity.

  Up in orbit, doing it's best impression of the Lockheed Martin "Blackswift"

The trickiest feat of engineering was not having it's 155 parts go their separate ways  on a crash landing when putting it down on Duna.

 

[Exothermos]

On 10/27/2016 at 5:10 AM, Rune said:

 Been wanting to use the cargo ramp that way for ages!

Yeah me too, but I couldn't crack it!  I'm trying to SSTA a cupola based rover.  

 

I get ungodly amounts of instability with any sort of Angle of Attack with the ramp part faced forward.  It creates huge lift (and drag) with anything more than 5 degrees AoA at speed, and the plane does backflips and rips apart.  Did you nullify that some how?

 

1) simple.  Unstable

2) move lift generating part closer to CoM.  Not much Better.

3) 5 degree pitch down on the part and push CoL further forward.  Same problem.

4) Go conventional to immediate success.

There were close to 10 other iterations before I gave up that I didn't bother to screenshot.  They would all SSTO easily, but if I messed up at all with the elevator it was instant disassembly. 

Edited November 1, 2016 by Exothermos

[stardog573]

4 hours ago, Exothermos said:

Yeah me too, but I couldn't crack it!  I'm trying to SSTA a cupola based rover.  

 

I get ungodly amounts of instability with any sort of Angle of Attack with the ramp part faced forward.  It creates huge lift (and drag) with anything more than 5 degrees AoA at speed, and the plane does backflips and rips apart.  Did you nullify that some how?

 

1) simple.  Unstable

2) move lift generating part closer to CoM.  Not much Better.

3) 5 degree pitch down on the part and push CoL further forward.  Same problem.

4) Go conventional to immediate success.

There were close to 10 other iterations before I gave up that I didn't bother to screenshot.  They would all SSTO easily, but if I messed up at all with the elevator it was instant disassembly. 

Rear-heavy planes tend to be unstable because of large lift/drag in front of CoM. That's why I distributed engines from front to rear to locate CoM at center position.(It also helps to prevent CoM shift by cargo load/unload) But even with that, it still needs rear airbrakes as stabilizer during reentry. 

[Rune]

6 hours ago, Exothermos said:

Yeah me too, but I couldn't crack it!  I'm trying to SSTA a cupola based rover. 

I get ungodly amounts of instability with any sort of Angle of Attack with the ramp part faced forward.  It creates huge lift (and drag) with anything more than 5 degrees AoA at speed, and the plane does backflips and rips apart.  Did you nullify that some how?

 

1) simple.  Unstable

2) move lift generating part closer to CoM.  Not much Better.

3) 5 degree pitch down on the part and push CoL further forward.  Same problem.

4) Go conventional to immediate success.

There were close to 10 other iterations before I gave up that I didn't bother to screenshot.  They would all SSTO easily, but if I messed up at all with the elevator it was instant disassembly. 

Ohh, the infamous CoM/CoL indicator is screwing you over. See, let me show in pics (BTW, notice how I did the completely opposite thing with the cuppola?):

That looks like a very far back CoL, right? Well, it isn't, really. The game isn't really showing the true center of pressure, just the center of pressure of all the parts with lift ratings. Want to see an even more dramatic effect of large body lift (relative to wing lift) screwing with stability? This is what I had to do to make my reusable boosters passively stable when dry:

And that is only barely stable.

 

Rune. Sadly, until they fix it, the only way to find the true center of pressure is trial and error.

Edited November 1, 2016 by Rune

[Val]

3 hours ago, Rune said:

Sadly, until they fix it, the only way to find the true center of pressure is trial and error.

Agreed. CoL is not the same as Center of Pressure. Using CoL as an indicator of stability only works when you have relatively big wings, compared to rest of craft.

As your crafts show, small wings don't affect the CoP much, so you have to compensate by moving them far back, thereby pulling CoL far back, too.

What we need is an indicator for CoP. 

[chrisb2244]

I think there's a mod for 'true CoL' or something like that. Has anyone used it (and want to give opinions?)

[kotysoft]

Hi everybody. I proudly presenting my new MK3 cargo SSTO, callsign KUMBO-03. Made by KSP 1.2 stock parts. I'm not a professional guy, just an enthusiastic player who loves to build things but noob in flying things.
 

It is very hard to control this spaceplane (for me at least), but it can transport 100tons of cargo into LKO and come back. Long time ago I didn't built a spaceplane, I don't know it is good or average in KSP v1.2?

 

[TheEpicSquared]

@kotysoft First off, 100 tons to LKO with an SSTO is incredible. Well done.

Second, since I'm not at all experienced with making SSTOs, take the following advice with a (large) grain of salt.

Here's the "advice": Maybe you could swap out the wings for the Big-S Delta wings? They hold fuel, so that might give you extra room for error. 

Remember that what I'm saying could be completely wrong - as I said, I know next to nothing about SSTOs .

[Val]

3 hours ago, chrisb2244 said:

I think there's a mod for 'true CoL' or something like that. Has anyone used it (and want to give opinions?)

It still only shows CoL. Not Center of Pressure, Center of Drag or Aerodynamic Center, which is what you need to know for stability.

 

[Rune]

On 1/11/2016 at 5:54 PM, chrisb2244 said:

I think there's a mod for 'true CoL' or something like that. Has anyone used it (and want to give opinions?)

I have the opinion that it is a mod I would have liked to have known about, a long time ago. Thanks for bringing it up!

23 hours ago, Val said:

It still only shows CoL. Not Center of Pressure, Center of Drag or Aerodynamic Center, which is what you need to know for stability.

 

CoP, CoL, CoD, we are getting a bit more philosophical/sciency here than KSP's aerodynamic model warrants. CoP would be the most useful if we only had one indicator, but a CoL that takes into account body lift is close enough for government work (only drag would be missing, and it easy to keep draggy parts on the back). After all, if you really wanted to get fancy about it, you would need the stability derivatives graphed, FAR-style. Then, and only then, you could see the influence of all the fancy stability-inducing tricks without test flights (high wings, dihedral, the various tail configurations...). Me, I kinda like the need to test-fly my creations a bit to find their characteristics.

 

Rune. BTW, awesomely informative post you have linked there at the end of your sig, Val.

[Val]

11 hours ago, Rune said:

BTW, awesomely informative post you have linked there at the end of your sig, Val.

Thank you

And to keep on topic, here are some pictures of my 100 t payload SSTO spaceplane that i just updated for KSP 1.2.

Craft file and flight instructions

[Arugela]

This is a WIP, but it can technically get into orbit with at minimum 300 tons and possibly much more. It's about 900 parts atm. so it's hard to fly because of lag. And it does not have Electrical RCS. It must have that placed in the cargo bays. My current version may not have enough. Still testing air intakes also to get rid of a problem where the Whiplashes loose air and start spinning the craft around 20k and mess up the flight. This is basically another one of my massively overdone planes.

Set your altitude early or you may not be able to adjust it later. And if you want to you can easily fit mining equipment and what not to extend the range. I'm hoping this thing can get alot to LKO because of the lift. Then I can get larger loads to wherever I want.

And the only shortcuts atm are for the engines. A lot needs to be done with it still.

48 Rapiers

48 Whiplashes

48 Nervs!

And around 500tons empty with around 500 tons fuel.

This is what I call a Dumb Cargo plane. It has the basics and the rest need to be put in as part of the cargo... It needs plenty of work still. 8)

https://www.dropbox.com/s/qqzvzsn08vtzhbr/IDGAD Cargo Plane.craft?dl=0

Edit: https://www.dropbox.com/s/atelir5wn2bj46u/IDGAD Cargo Plane 3_2 Load Test.craft?dl=0 <-(1,282Parts; 2,100tons)Load test of version 3.2 with 850tons and full fuel. Just in case anyone wants to test this for fun. I'm doing the test flight now! 8) If it can get to orbit with 52000 LF left it can possibly make it to minimus with 850 tons and refuel.

It also keeps crashing my game every time I get a really good flight going....

BTW, IDGAD Is short for, "I don't give a darn!" It is a name I use for the planes when I have plane making writers block and just start putting stuff together to make stuff. Not that that is different from what I do normally. It could also be called slapstick plane comedy. Slap it together and stick it on the runway and see how funny it is to fly. 8d This one wasn't that funny... But it did keep getting bigger and bigger and bigger. I think that counts as funny in some way. Right!?

Edit: There is/was also a problem with the nervs firing alone causing the plane to veer to the side in space... I don't know if I've resolved this yet. This is obviously a major issue if going beyond kerbin. Or even for getting to orbit conveniently.

Here is version 2: https://www.dropbox.com/s/6hhlo7cuocpbm99/IDGAD Cargo Plane2.craft?dl=0

I added more cargo bays because I need to test out it's max weight limit. The equivalent of 3 large cargo bays filled with full large ore containers apparently wasn't enough.... Still have to find a way to compensate for the COM/COT alignment thing. 8)

Update:

Version 3.2

This one has the cargos on the side to simplify the design. It could be good for deploying multiple submarines on laythe. 570.5 tons empty and around 1200tons full of fuel. I haven't tested the carrying capacity yet. It lands on the water with a lift to drag ration of about 6. it is very good for gentle water landing. Of course this was tested empty... Still have to see how it acts full load.

Edited November 4, 2016 by Arugela

[Monsterlunch]

The ArcJet MK4 is my current WIP SSTO. I'm quite proud that it made Orbit in its first design revision

[Rune]

1 hour ago, Monsterlunch said:

The ArcJet MK4 is my current WIP SSTO. I'm quite proud that it made Orbit in its first design revision

That is a seriously sexy spaceplane, IMO. A shame about the control surfaces not following the wing's curvature perfectly... mayhaps you could hide them inside the wings? Or use inverted control surfaces a bit farther back instead, in a hort of tail that is parallel to the wing's trailing edge?

Also, as usual, I have a feeling you could push that payload class with less engines, increasing the design's payload fraction. Six should give you more than enough for a sporting ascent, as long as you go supersonic close to the ground. Less engines would also move the design's CG forward, especially empty, so it would help reducing the amount of control surface area you need at the back.

 

Rune. Throwing in the usual 0.02$.

[AeroGav]

On 01/11/2016 at 5:54 PM, kotysoft said:

Hi everybody. I proudly presenting my new MK3 cargo SSTO, callsign KUMBO-03. Made by KSP 1.2 stock parts. I'm not a professional guy, just an enthusiastic player who loves to build things but noob in flying things.
 

It is very hard to control this spaceplane (for me at least), but it can transport 100tons of cargo into LKO and come back. Long time ago I didn't built a spaceplane, I don't know it is good or average in KSP v1.2?

Like everyone else, I want to congratulate you on 100 tons !  I don't know why i've never built that large, maybe it's because obsess over detail and never get round to just expanding the design.  More is more, after all.

I can see a couple of things I might want to change.   

1. It looks like you are really struggling for pitch authority.  You could try copying my design of canard -Basically two Tail fins mounted back-to-back,  the rear one reversed 180 degrees. On the tips of this pair, are mounted an advanced canard.   You may need to set the rear tail fin to -100% (or -60% or whatever) pitch authority in the tweakable  to stop it moving the wrong way.
2.  I can see an opportunity to reduce the drag of your craft in a few places.  You've got 2.5m parts mounted to mk3 fuselage stacks, for the least drag you must always use an adapter when mounting parts that are not the same diameter.   So you'd go Mk3 fuselage > Mk3 to 2.5m adapter > Poodle engine  or Quad engine mount.         Finally you should be aware that engines with a rear attach node - basically all rockets and the rapier - have very high drag unless you mount a cone to them (of same diameter as the engine) then offset it inside the engine.    The game treats this "open node" in the same way it would an inline cockpit with no nose cone on the front - ie flat plate drag.  Jet engines (which do not have rear attach nodes) have similar drag values to rocket engines with cones on the back.

 

Low drag parts to begin or end a stack -

nose/tail cones 

jet engines with no rear attach node

intakes

high drag parts

open nodes

docking ports (that includes the shielded one, it is really draggy)

heat shields

basically anything blunt and not pointy

3.  I just noticed there appears to be only one vertical stabilizer surface.   I don't think that's enough on something that size.   You can see on my design, i've got about 4 sets of strakes mounted vertically to give more yaw stability.  They are doubled up too - extending above and below the wing.  You dont need  a lot of rudder area because you probably don't use the rudder all that much, but just plenty of surface area providing passive stability.

EDIT - yikes - i just saw a vertical stabilizer mounted on the "chin" of the airplane, right under the cockpit.  Vertical surfaces mounted ahead of CG reduce yaw stability,  they are worse than useless !  That said, the only problem you appeared to have in the video was with pitch control.

4.  From about 250 m/s to 400 m/s is the high drag transonic region.  I normally level off here or even let the plane arc over into a shallow dive.   But yours appears to have no problem going supersonic in a climb, it has so many engines !

 

Edited November 5, 2016 by AeroGav

[kotysoft]

@AeroGav Thank you so much for useful tips! Few of them I already experienced once I started to create a long-range explorer SSTO, but many of them are new for me. BTW I made a big mistake with KUMBO-03. It's built to be stable by using mechjeb SmartASS. When I realized current (dev) version of MechJeb has some issues with spaceplanes, I could make better planes with modified CoM<>CoL and control surface positions, and it's looks more stable. 

Currently I have some issues with my (1.2.1) game (or mods, i don't know), but have random crashes very often  

[AeroGav]

48 minutes ago, kotysoft said:

@AeroGav Thank you so much for useful tips! Few of them I already experienced once I started to create a long-range explorer SSTO, but many of them are new for me. BTW I made a big mistake with KUMBO-03. It's built to be stable by using mechjeb SmartASS. When I realized current (dev) version of MechJeb has some issues with spaceplanes, I could make better planes with modified CoM<>CoL and control surface positions, and it's looks more stable. 

Currently I have some issues with my (1.2.1) game (or mods, i don't know), but have random crashes very often  

I have crashes also - access violation errors.  It turns out there is a bug with the aerodynamic forces overlay currently, once enabled game is liable to crash within the next 5 or 10 minutes, especially if you highlight a part in flight.  Thing is, i use the aero data gui all the time.  There's a workaround on tech support forum - turn off part highlight fx

regarding stability, i found RCS build aid very helpful, tells you where the CoM will be when empty, which you can do manually but this saves a lot of time, it also tells you how much torque you get from engine thrust.  I discovered that even simple single engine SSTO with an engine on rear fuselage had some off-axis component, due to the landing gear making the centre of mass slightly below centreline of ship, or alternatively the tail fin or wing dihedral might raise it slightly above.     To a lesser degree, TrueCoL is good too - takes account of fuselage lift, but it does sometimes loose the plot, especially if the root part is mounted upside down or back to front it gets confused.

[Monsterlunch]

7 hours ago, Rune said:

That is a seriously sexy spaceplane, IMO. A shame about the control surfaces not following the wing's curvature perfectly... mayhaps you could hide them

Thanks very much, I'm glad you like it.

I do not exactly understand though what you mean by following the wings curvature - do you mean the part where they dont align with the wings tip perfectly?

7 hours ago, Rune said:

Also, as usual, I have a feeling you could push that payload class with less engines, increasing the design's payload fraction. [...]

Well, i just had a quick look at your main ship posting thread thingy. Talking about your Longsword SSTO, which carries big oranges to orbit on 6 rapiers you said this:

On 25.4.2013 at 9:04 PM, Rune said:

And the margin is very tight! It has, therefore, quite the piloting requirements. Don't worry! There is a piloting guide in the description and everything. I guess that's what happens when you go tight on TWR on order to maximize payload ratio...

You seem to be very obsessed about your payload ratios. I however am only obsessed about my crafts factor of sexiness. Which is through the roof on this craft btw.

To be honest though, I'm just lazy. And a crappy pilot.

Also, moar pictures!

 

Edited November 5, 2016 by Monsterlunch

[Rune]

2 hours ago, Monsterlunch said:

Thanks very much, I'm glad you like it.

I do not exactly understand though what you mean by following the wings curvature - do you mean the part where they dont align with the wings tip perfectly?

Well, i just had a quick look at your main ship posting thread thingy. Talking about your Longsword SSTO, which carries big oranges to orbit on 6 rapiers you said this:

You seem to be very obsessed about your payload ratios. I however am only obsessed about my crafts factor of sexiness. Which is through the roof on this craft btw.

To be honest though, I'm just lazy. And a crappy pilot.

Also, moar pictures!

Hum. That SSTO you speak about in my page is about four game versions old. These days, SSTOing is much easier. And you know, they say something about showing by example, so you know, what the heck, it's been a long time since I reverse-engineered something from a picture. This is the kind of thing I'm talking about:

Mach 1 at 1:09. Notice how I'm pretty much level. The RAPIERs have gotten a good bite of air, and my limited intake area (two shock cones and two precoolers can feed six RAPIERs without issues) means I'm going to start accelerating, seriously.

Mach 2.4 at 2:14. Vertical speed is already 143m/s, and I barely increased pitch, just continued in a straight line as Kerbin curves under me. The only pilot input is setting the initial speed run, and correcting the inclination every now and then with roll. Maybe increasing pitch a bit at the same time, because this bird is a bit more sporty than I'm used to.

Mach 4.7 at 3:20. Time to switch modes, because thrust is going down the drain. A pretty high RAPIER cutoff speed, if I may say so. I'm usually pretty happy getting 1,300m/s, this design is sporty even with six RAPIERs. Notice this is about the highest AoA in the whole flight, and my vertical speed is a healthy >300m/s.

Apo of 75kms at 4:27. It's all coast from here, so timewarp time, and to map view to plan the circularization. Running a tad short on dV at his point.

Orbit circularized at 8:38. I didn't balance the fuel right because it was the first flight, so I had to dip into the payload's oxidizer. But there's plenty of liquid fuel left over and lots room for oxidizer, so I can say with confidence that it can lift that Big Red, and as I said, be quite sporty about it. With more fuel tanks, it can probably lift a bit more than that in fact.

Sorry if all that sounds a bit pedantic, but I'm a bit tired of all the people saying a properly balanced design is somehow boring to fly. A good SSTO gets about two thirds of its mass to orbit, half of which can be payload, in about the same time a rocket does. The only extra time you spend on it is designing it properly, which I'll be the first to admit is much trickier (which is why I give all the tips on it I can), and recovering it, which is the actual time the piloting skills come into play (and trust me, those are mostly practice).

Also, you like what I did with the tail? It also has a couple of elevons in between the RAPIERs, where they don't spoil the lines but are still clickable, and no other hidden control surfaces. All in all, a fun ship to fly, but the CoG/CoL mismatch is quite hard to overcome with that payload bay on the front, and the CoG so far back, so it'll always handle weird either full or empty. Of course, I knew what I was talking about with the powerplant, because my Orca can lift a Big Red on six RAPIERs... and quite a bit more. Like a 4+mT crew cabin and a VTOL rocket system more.

 

Rune. That was actually a lot of fun, hope you find it useful too.

Edited November 6, 2016 by Rune
Long post, lots of mistakes ^^'

[Monsterlunch]

12 hours ago, Rune said:

*Making a very good point*

Well you got me on this one. Thanks for the design advices! Now, on to the drawing board!

The tail looks fabulous! I'll see what I can do about my own one.

Edit: I just had a quick go on it, reducing intake area really results in a huge reduce of drag, saving me lots of trouble in the initial ascent!

Btw, it is just incredible how much effort some people put in this forum! Keep it up!

Edited November 6, 2016 by Monsterlunch

[AeroGav]

12 hours ago, Rune said:

Sorry if all that sounds a bit pedantic, but I'm a bit tired of all the people saying a properly balanced design is somehow boring to fly. A good SSTO gets about two thirds of its mass to orbit, half of which can be payload, in about the same time a rocket does. The only extra time you spend on it is designing it properly, which I'll be the first to admit is much trickier (which is why I give all the tips on it I can), and recovering it, which is the actual time the piloting skills come into play (and trust me, those are mostly practice).

The other charge people throw at lower powered designs, is that they are hard to fly.     I think this is also a fallacy.  Take two SSTOs with same payload fraction, one is overpowered,  one less so.    The OP one will have more engine mass and therefore leave less for fuel, and you'll be on the brink of running out as you reach orbit.  Tiny differences in flight profile will make the difference between success or failure, and it will be hard to maintain an accurate one with wild surges in power and everything happening over such a compressed period.     

It's not like flying a rocket, where excess power can allow an upper stage to recover from a bad gravity turn, and not fall back to the atmosphere and burn up.   A plane has wings.  Most of the time the margin between running out of fuel and circularising sucessfully is a lot smaller than the thrust:drag ratio of even an underpowered aircraft.

Like my passenger liner i linked near the top of this page 

 

it has a TWR on takeoff of just 0.3, takes nearly half an hour to get to orbit.   But it flies a lot like a Boeing in Microsoft Flight Sim,  if you look at the aero data gui there is nearly always twice as much thrust as drag, if not more.   It is stable and all you do is occasionally add or remove a notch of pitch trim while taking screenshots. Look for the best lift:drag ratio, bearing in mind the optimum is about 2AoA at 100 m/s rising to 5 supersonic.  Add a notch of trim,  ratio get worse? try adjusting in the other direction.

 

 

[Guest]

 

This is a mk3 SSTO with a ramp for rovers and vertical landing capability (fuel balance both axis)

[Val]

1 hour ago, RevanCorana said:

This is a mk3 SSTO with a ramp for rovers and vertical landing capability (fuel balance both axis)

Very nice looking, great lines, but hard to see from your pictures how the VTOL is implemented? Would you mind posting pics of that or explaining?

[Guest]

.

Edited December 13, 2016 by RevanCorana