SSTOs! Post your pictures here~

[The Destroyer]

Glorious grand tour SSTOVTOL

[Rune]

12 hours ago, AeroGav said:

Interesting looking ship.  While you were doing that,  I built this - 

 

I stuck to my "nose 5 degrees above prograde" mantra throughout the nuclear powered part of the ascent, until my wings started glowing yellow hot.  Newsflash - airliner wings aren't built for spaceflight.  Then I wound on a load more nose up pitch trim in a desperate bid to gain height before we melted.   Not sure how much the brown trouser maneuver cost us but i became so preoccupied with the temperature gauge i missed MECO and ended up in a really wonky orbit.

 

I make that about 2500 dV.

I'm surprised your sci-fi looking rhombus ship took so much more fuel to get to orbit, it looks really similar to mine.  The only differences i can see

• i think the circular intake has less drag than the ramp, and i'm only using one of them (poor air gathering above mach 3, but that doesn't matter with Panthers) - tiny difference
• cones on the back of my nukes - i've attached 1.25m nose cones to the back of my nukes then offset them forwards so they don't get heated by the exhaust.   also make sure you disable the shroud or your ship can self disassemble when the engine is activated via staging (the shrouds appear to be made of lead and rip chunks out of the wing)
• i got bigger control surfaces.   i have dialled down the authority a bit.   Large surfaces at a small deflection angle make less drag than small ones with big angle

Still, not sure how things are so far off.

If you press ALT + F12 to bring up the debug menu, then go to physics, aero, and check the "display aero data gui" box, you can see the lift:drag ratio of your airplane overall.   I adjust the pitch trim to try get best l/d - typically 3.4 to 1 or so, during the hypersonic ascent, at 4 or 5 aoa.

Actually, what is screwing with you guys is drag. You are trying to make work a really inefficient path to orbit.

See, any spaceplane takes a pretty inefficient path to orbit. Nowhere near the 3,5km/s that a rocket needs, more like twice that, or more. The thing is, in an airbreather that doesn't really matter, because you have four freaking thousand seconds of Isp. With that Isp, you could build a rocket with ~40km/s, easy, compared to the ~4km/s that is hard to get on KSP rockets, and you could single stage your way to Eve's surface and back. See how OP airbreathers are? That is why you can say screw it, I will eat all the losses (aerodynamic drag, and gravity losses, AKA gravity drag) just for the sake of using this stupendous engine as long as I can.

And that is all well and good until you run out of air to make your 4,000s engine go. Then, you are a rocket just like any other. That is critical. Rockets are severely limited in Isp, therefore they have to absolutely minimize drag and gravity losses. Adding 50% of dV to orbit would kill them, for example. That is when a high TWR (to minimize gravity drag) and a steep ascent to orbit (to minimize drag losses by getting outside the atmosphere ASAP) is crucial. It is also the reason why a RAPIER can get the most amount of cargo to orbit: good TWR on rocket mode, and the highest airbreathing cutoff speed. And it is also the reason nuke designs waste tons of dV getting to orbit: poor TWR once the airbreathers cut. All the extra dV of their high Isp goes into gravity and drag losses. And the shallower your ascent is once you have switched to rocket power, the more dV you will waste on drag. That is why I always make a point of switching modes on the RAPIER as soon as my vertical velocity starts to drop, even if I am still accelerating horizontally.

 

Rune. The nuke-equipped design I showed earlier, with several times the payload of yours and the same amount of engines? 3,5km/s on LKO, thanks to carrying oxi for a high TWR climb.

Edited January 10, 2017 by Rune

[AeroGav]

16 minutes ago, Rune said:

Rune. The nuke-equipped design I showed earlier, with six times the payload of yours and the same amount of engines? 3,5km/s on LKO, thanks to carrying oxi for a high TWR climb.

Which one Rune, this?

Compared with this?

My craft (built for a 3 engine challenge) has 35T takeoff weight, went to 150km x 150km orbit (per rules of challenge) with admittedly only 2T payload (mk1 cockpit and cabin) vs  4T in yours (mk2 cockpit and cab, twice as many kerbals).  But mine also brought  9.88tons of LF (1976 units) up there.  So a "payload" fraction of 34% to 150km orbit which isn't terrible.    The limiting factor on what can be lifted is the single Rapier engine.   Other entries for the challenge went with 2 rapier 1 nuke, which enables a higher takeoff weight.  There's only so much  mass one rapier can bring through the sound barrier after all.    Even so this ship came second.  The 2 R 1 N designs had higher starting mass but a lot of that got used up during the climb to orbit (oxidizer) so their delta V in orbit wasn't that much higher.  And mine had higher TWR in orbit due to having 2 N vs 1.

Quote

 

Actually, what is screwing with you guys is drag. You are trying to make work a really inefficient path to orbit.

See, any spaceplane takes a pretty inefficient path to orbit. Nowhere near the 3,5km/s that a rocket needs, more like twice that, or more. The thing is, in an airbreather that doesn't really matter, because you have four freaking thousand seconds of Isp. 

And that is all well and good until you run out of air to make your 4,000s engine go. Then, you are a rocket just like any other.

 That is when a high TWR (to minimize gravity drag) and a steep ascent to orbit (to minimize drag losses by getting outside the atmosphere ASAP) is crucial. It is also the reason why a RAPIER can get the most amount of cargo to orbit: good TWR on rocket mode, and the highest airbreathing cutoff speed. And it is also the reason nuke designs waste tons of dV getting to orbit: poor TWR once the airbreathers cut. All the extra dV of their high Isp goes into gravity and drag losses. And the shallower your ascent is once you have switched to rocket power, the more dV you will waste on drag.

 

In a spaceplane you want to keep a good margin of thrust to drag ratio , in the same way that in a rocket you want to keep a good margin of thrust over gravity.  That is because the wings make lift to counteract gravity, so they don't usually have gravity losses, but in creating this lift, they make extra drag (directly from the wings, and also from the body going through the atmosphere faster, lower than you'd otherwise choose to).  As a result,  lift:drag ratio becomes as important as TWR.

Example,  at the end of the airbreathing run, your plane is being pulled down by 120kn of gravity.

At these speeds, orbital freefall effect is already cancelling half, but you still need to find 60kn of upward force to stay in the air.

In a mk1 or mk3 with angled wings (incidence) , a L/D > 4:1 is possible.   In a mk2 with angled wings, or mk1 without angled wings (but generous wing area) you can still get over 3:1.

So,  with 3:1 L/D you'll have about 20kn of drag from staying up.

Let's say you only have one nuke - 60kn thrust.       You are losing about 33% of your potential delta V to drag/gravity combined.

However, throughout that burn from airbreathing to orbital velocity, the lift requirement is going to drop, as orbital freefall takes up more and more of the load.  Towards the end of the burn, drag losses will be approaching zero.  So the true figure i suspect will be somewhere in between (half?).

Quote

That is why I always make a point of switching modes on the RAPIER as soon as my vertical velocity starts to drop, even if I am still accelerating horizontally.

If horizontal velocity is decreasing you are not making as much lift as you need to sustain flight, eventually that will turn into a descent. In level flight, you might actually be making less thrust than drag at this point .  I switch mode when thrust falls to less than 130% of drag in level flight during the speedrun.    Even if i'm getting four times the ISP, it does you no good if three quarters of your power is going to waste on drag.

 

[Rune]

59 minutes ago, AeroGav said:

The limiting factor on what can be lifted is the single Rapier engine.   Other entries for the challenge went with 2 rapier 1 nuke, which enables a higher takeoff weight.  There's only so much  mass one rapier can bring through the sound barrier after all.    Even so this ship came second.  The 2 R 1 N designs had higher starting mass but a lot of that got used up during the climb to orbit (oxidizer) so their delta V in orbit wasn't that much higher.  And mine had higher TWR in orbit due to having 2 N vs 1.

Exactly the point I was making. High TWR at the start of the climb is really important, and LFO engines excel at that. High TWR in orbit is just dead engine weight. If you want to max out in-orbit dV, just put the minimum amount of nukes for TWR>0.1, and lift them to almost-orbit on RAPIERs. If you want the maximum payload on orbit... stick to RAPIERs only and put no nukes, both your total payload and your payload ratio will be higher most of the time. The proof for that last one is in the payload ratio challenge, which went over 55% payload on 6-1 RAPIER-nuke designs, with pure RAPIER designs a close second (and still over 50%). The nuke does have a very high Isp for a rocket... but it is barely worth it, because of the low TWR, for such a small dV expenditure as the suborbital->orbital transition.

 

Rune. I'll be the first to say that is a very minmaxed design, but it is trying very hard to make a flawed premise work.

Edited January 10, 2017 by Rune

[AeroGav]

 

24 minutes ago, Rune said:

 

Quote

 

The limiting factor on what can be lifted is the single Rapier engine.   Other entries for the challenge went with 2 rapier 1 nuke, which enables a higher takeoff weight.  There's only so much  mass one rapier can bring through the sound barrier after all.    Even so this ship came second.  The 2 R 1 N designs had higher starting mass but a lot of that got used up during the climb to orbit (oxidizer) so their delta V in orbit wasn't that much higher.  And mine had higher TWR in orbit due to having 2 N vs 1.

 

 

Exactly the point I was making. High TWR at the start of the climb is really important, and LFO engines excel at that.

Not quite, this is a discussion about closed cycle climb isn't it?  My 2 nuke 1 Rapier ship is very comfortable with 35t ToW  in closed cycle mode, but the problem would be getting past mach 1.

Not to dispute that Rapiers are best for delivery to low orbit. Nukes are for going further afield.

Anyway I did  a test to see how much of my theoretical delta V is being lost, on the Cormorant.

The end of the speedrun.  Drag is catching up with Thrust.   We're only at 1.5degrees angle of attack, which is lower than optimum for efficiency - our lift:drag ratio has fallen to just 2.4 to 1.   But we don't want it to climb out of the atmosphere before every last drop has been milked out of airbreathing mode.

1500 m/s at 21.76 km.   4753dV remaining.

After lighting the nukes, we're on the expensive juice, so i pitch up to an AoA that gives us the best possible lift:drag ratio. Climb rate goes from 2m/s to 187 m/s in less than a minute.

After about 4 minutes, our AP goes out of the atmosphere.     

So, results?

At MECO, we had 3879dV.   After circularising to 73 x 73 km,  3816dV

Overall we've used 937dV to increase our velocity from 1500 to 2100.

So 600 m/s of acceleration, 27 m/s to circularise the orbit.

We also climbed from 21 to 73km, which would cost us some m/s too.  I don't know the formula for that, but we did loose about 80 m/s velocity going from 50km to 70km.       I 'd guesstimate drag losses about 20%?

 

[lodger]

ASES SP2 SX

 

[Samniss Arandeen]

If LKO shuttle work is all you need, nuclear engines are more trouble than they're worth. I personally prefer LV-909/Rapier combos, such as...

Project Crossbow

Powerplant: 2x Terrier, 2x Rapier

Crew Capacity: 6 Kerbals

Payload Capacity: approx. 1.5t

 

Full Mission Photography

http://imgur.com/a/M6pSp

[Soda Popinski]

I'm playing an old 0.23 save game.  To complete my mission, I have to fly up the first big SSTO I ever made (had to carry 7 kerbals).  This was before large plane parts was a thing.  So I had to use 2.5m rocket parts, which gave no lift.  Hence the gigantic wings.
 

 

[Speeding Mullet]

I haven't made an SSTO in absolutely ages.  In fact I haven't made one since before the significant aero changes occurred as I simply lost the ability to do it.  That really had to change so I put my mind to it and have designed and flown this mission recently.  First some stats:

Name:  Mullet Dyne Cross Wing (Variant 5)

Parts: 86 (including payload)
Mass: 43.155t
Cost: 81,464 (including payload)
Power: 3 x CR-7, 2 LV-N

Mission Report - Click here

Craft File - Click here

SM

[hurdurdur]

My one more go at the shallow ascent. At 50km the crew cabin and intake wanted to catch fire really bad (last mm missing from explosion by the red bar visual) but somehow stayed together, on descent just had to rotate-tumble like crazy out of control in order not to burn up the intake.

 

Used 1117 units of fuel to get up there (77x80 orbit), but since i had a tank extra this time i had 483 left - a bit better than the 2 intake plane, but i truly disliked almost catching fire. Handling was excellent, just had to control authority on the  canards. I don't use the reverse cones on engines, sort of feels like too much cheating.

 

edit: when i switch the cargo area in front of the cabin used ramp intake instead then i got way less heating problems and nearly the same fuel economy, had to pitch up more agressively after 1500m/s surface speed.

Edited January 10, 2017 by hurdurdur

[AeroGav]

58 minutes ago, hurdurdur said:

My one more go at the shallow ascent. At 50km the crew cabin and intake wanted to catch fire really bad (last mm missing from explosion by the red bar visual) but somehow stayed together, on descent just had to rotate-tumble like crazy out of control in order not to burn up the intake.

 

Used 1117 units of fuel to get up there (77x80 orbit), but since i had a tank extra this time i had 483 left - a bit better than the 2 intake plane, but i truly disliked almost catching fire. Handling was excellent, just had to control authority on the  canards. I don't use the reverse cones on engines, sort of feels like too much cheating.

 

edit: when i switch the cargo area in front of the cabin used ramp intake instead then i got way less heating problems and nearly the same fuel economy, had to pitch up more agressively after 1500m/s surface speed.

Yes, the more fuselage sections the cockpit is back from the nose, the less hot it gets.  The more wing area you have relative to weight, the less heat also,  because you climb faster without having to push the nose up too much.

Re: reverse cones.  I don't see it as cheating,  it basically lowers the drag to the level of a jet engine of the same diameter.  It's not actually the engine itself that's causing the drag on the nerv, it's the unused attach node on the back of the engine.  The game engine treats that as flat plate drag, like you'd not bothered to put any kind of nose on an inline cockpit.   Made sure the node is occupied - no penalty.

 

[AeroGav]

@hurdurdur here's another oxidizer free ssto i built for mid career mode.  It does contain a whiplash since like the nuke, it's a 500 science cost part.   But it has to get by without fuel-carrying wings.       Spent a lot of time adding extra little bits here and there till i'd tuned out every little handling quirk.  Won't put as much @ 70km as a whiplash/dart,   but try asking the whiplash/dart to take some science juniors to Minmus and see what it thinks.

https://kerbalx.com/AeroGav/Firefox-II

Given the constraints, i did use all the aero tricks i knew.    Cones on the back of nukes? check.     Angled wings with 5 deg. incidence? check..

[AeroGav]

@Rune   I think the reason I've ended up with such a differing opinion on SSTO performance/flight profile is i've spent too much time flying my own aircraft.      Downloaded this monster a few hours ago from @mystik- and what you are saying makes perfect sense when you're flying one of these!

He's heavily invested in maxing the TWR (partly because he wants to be able to land it on Tylo) and kept aero stuff to a min (dead weight).

My "Cormorant" is woefully underpowered but has so much aero stuff it looks like a motor glider.       Thoth flies more like an airbreathing rocket,  L/D ratio is about 1:1 at high speed, so indeed, once you're no longer making good power on air breathe mode get upstairs ASAP.

Needless to say, the Thoth's flight profile doesn't work so well on the Cormorant..

[Thingymajigy]

k people, who knew the Aeris 4A was this good

cos I definitely didn't

[Kaiser82]

On 12/31/2016 at 3:11 AM, Jett_Quasar said:

It's not your typical SSTO since it uses only rocket engines but it can put a 60T ISS style space station in orbit and return back to KSC.

*Assembly required...

Jett

 

 

 

 

 

I absolutely love this

[Jett_Quasar]

39 minutes ago, Kaiser82 said:

I absolutely love this

I'm planning on putting together a video to show how the station is assembled and then I'll be releasing the craft file.

Jett

[mystik]

8 hours ago, AeroGav said:

@Rune   I think the reason I've ended up with such a differing opinion on SSTO performance/flight profile is i've spent too much time flying my own aircraft.      Downloaded this monster a few hours ago from @mystik- and what you are saying makes perfect sense when you're flying one of these!

He's heavily invested in maxing the TWR (partly because he wants to be able to land it on Tylo) and kept aero stuff to a min (dead weight).

My "Cormorant" is woefully underpowered but has so much aero stuff it looks like a motor glider.       Thoth flies more like an airbreathing rocket,  L/D ratio is about 1:1 at high speed, so indeed, once you're no longer making good power on air breathe mode get upstairs ASAP.

Needless to say, the Thoth's flight profile doesn't work so well on the Cormorant..

Oh, I tried hard to make it fly better. I couldn't. Unfortunately the Thoth has reached it's designed limit. From here, there are a few ways to go:

 

1. I believe it is capable of landing and taking off from Tylo as it is now. It does require to visit some other moon first to refuel so a direct mission isn't possible. In fact, none of the missions can be direct, all must be done by "planet hopping". I launch it to orbit, then refuel it via another SSTO that carries lots of fuel, then continue the journey, not knowing it this will work for sure unless I try landing it there.

2. I think it is time to go 3 ways and experiment to see which is better:

a. Make it 4 horizontal tanks and engine ratio it currently has. Because each tank has to pull less central weight, this will increase the dv remaining, but as long as I keep it aerodynamic to not create too much drag. This model isn't really that great because it makes the ship huge, clunky and heavy. Because I intend to land on planets with low gravity this will become a problem because I won't be able to control it very well on landings. The Spike engine under the ship won't be enough if I double the weight. This has low chances of success.

b. Make it 3 tanks, making it look more like a prism. This requires switching to a delta wing to be able to carry the thing as the current layout will not allow for the thing to fly anymore. It is already on the limit and the wings would snap off the moment you try to make any maneuvers. Assuming you can actually take off. This has a moderate chance of success.

c. Create an orbital tug ship that launches separately and functions as a rocket instead of a space plane. Switch out the front claw with a docking port. Create something like a sky crane that tugs the space plane to preserve fuel on the main ship and use that to get places and use the ship itself to land and refuel and take fuel back to orbit to the tug ship to refuel. This will also allow me to add a backup propulsion system based on ION engines for emergency cases where I get stranded in space. I can add 30 engines and that should return it back in case it gets stranded. Since the tug ship does not need to land, it can carry ridiculous amounts of fuel and can be assembled in orbit via multiple launches. I can even create a dedicated part of it to decouple into a giant ISRU for low gravity objects to carry the crazy fuel needed to orbit. This has the highest chance of success but it will create a logistical nightmare for the non experienced user that has issues with docking. There will be a lot of docking. A LOT. More time will be spent preparing for missions than the actual missions. Not sure if that is very appealing to the normal user, but that means you can visit most of the places, except Eve. For that, I have to figure things out, maybe make a SSTO rocket that I can deliver there in advance then travel with the space plane and transfer the crew. Either way, it will enable people to fly everywhere, using 3 ships in total, one of which can be permanently left in Eve orbit for reuse.

Edited January 11, 2017 by mystik

[AeroGav]

23 hours ago, hurdurdur said:

Used 1117 units of fuel to get up there (77x80 orbit), but since i had a tank extra this time i had 483 left - 

I reckon just keep adding more fuel tanks, and wings to lift them with, while keeping same engine config, at some point you won't be able to break the sound barrier, but your delta v will go up and up.  It looks fairly light, not far from being able to go to Minmus.

[hurdurdur]

Talking of rockets-that-assist-from-air-breathings , here is my heavy lifter with inspiration from Skylon.

The rear wheel makes takeoffs and landings  a bit easier. The whole design is there to get high twr and lift anything i can fit into the double cargo bay to orbit (and to land back safely again). Enough power and control to forgive a lot of mistakes. Unmanned since the mk3 cabin part is too heavy, docking ports on either end just in case, engine weight in the middle to ease balancing and flight. It is advisable to burn pretty much all the fuel before the landing, this bird doesn't quite have the wing area to make pretty landings when it's heavy.

[Jens Lyn IV]

I've been on a quest to design an efficient SSTO to get a crew of six to LKO and back, and it took me in a few different directions, so here are three rather different results:

The reasonable solution; not the smallest, not the cheapest, but the fuel margin is very comfortable, and reentry is a cakewalk.

The efficient solution. Slim fuel margin, scary reentry, high stall speed - but it'll hit 1650 m/s on the jet.

The unreasonable solution: A triple-fuselage joke* of a spaceplane that performs a lot better than it has any right to.

Seriously, how do three Mk1 fuselages generate less aerodynamic drag than a single Mk2 fuselage at zero angle of attack?!

*Good luck reaching that docking port...

Edited January 12, 2017 by Jens Lyn IV

[Thingymajigy]

Finally made a fairly efficient (for me anyway) mk 3 plane

Slightly larger variant

[Thor Wotansen]

What are you using for engines in space?

[Rune]

On 10/1/2017 at 6:35 PM, Samniss Arandeen said:

If LKO shuttle work is all you need, nuclear engines are more trouble than they're worth. I personally prefer LV-909/Rapier combos, such as...

 

Project Crossbow

Powerplant: 2x Terrier, 2x Rapier

Crew Capacity: 6 Kerbals

Payload Capacity: approx. 1.5t

 

Full Mission Photography

http://imgur.com/a/M6pSp

Putting chemical engines next to RAPIERs is a waste of a good engine. You are already carrying pretty decent chemical engines inside the RAPIERs, and if lugging extra nukes is barely worth it for the climb to LKO, I can guarantee you lower Isp engines will do worst. Bring an extra mT of LFO instead, and you will see that those extra 40 seconds in Isp are totally not worth their weight.

On 11/1/2017 at 1:03 AM, AeroGav said:

@Rune   I think the reason I've ended up with such a differing opinion on SSTO performance/flight profile is i've spent too much time flying my own aircraft.      Downloaded this monster a few hours ago from @mystik- and what you are saying makes perfect sense when you're flying one of these!

He's heavily invested in maxing the TWR (partly because he wants to be able to land it on Tylo) and kept aero stuff to a min (dead weight).

My "Cormorant" is woefully underpowered but has so much aero stuff it looks like a motor glider.       Thoth flies more like an airbreathing rocket,  L/D ratio is about 1:1 at high speed, so indeed, once you're no longer making good power on air breathe mode get upstairs ASAP.

Needless to say, the Thoth's flight profile doesn't work so well on the Cormorant..

 

Nope, if anything I'm known for low TWRs. Basically minimizing engine mass, so I can get a better mass ratio, which is the main thing on rocketry. And my usual flight profile is a straight line to orbit (don't touch the controls at all in some designs, once I set the speed run at sea level). In fact, I use no autopilot mods, so those >30% payload fractions I boast about were flown by hand.

...well, there's the Arrow, but that's a pure-rocket chemical SSTA that would do a vertical takeoff on Tylo and sees air as a hindrance. Call it an exception.

So recapitulating, I can no longer remember what we were disagreeing in, therefore I will ask you this question: in what way are liquid-fuel only SSTOs better? Because for the life of me, I can't see any... other than the challenge in building them, I see no point in them.

17 minutes ago, Thor Wotansen said:

What are you using for engines in space?

Judging by the exhaust, I'd say Vectors. Nice TWR and decent vacuum Isp.

22 hours ago, Jens Lyn IV said:

Seriously, how do three Mk1 fuselages generate less aerodynamic drag than a single Mk2 fuselage at zero angle of attack?!

Right? I've been trying to make the damn single-RAPIER design I've been after for a long time, I can't replicate the payload fraction of my bigger designs, because drag on those things is seriously unreasonable. I was thinking I must have left some wonky open node at first...

 

Rune. But they look so nice!

[renhanxue]

Many people play around with Panther powered SSTO's in career mode because they don't have the actually useful parts (Rapiers) yet. I mucked around with them so much that I forgot to actually go anywhere other than LKO for days on end. I finally did unlock the Whiplash so I guess I need to go do grownup things now but I did get a Panther powered "let's get two free kerbonauts from LKO in one launch" vehicle preeeetty optimized.

While it is somewhat anathema to the spirit of the Kerbal Space Program, it is a fact that how you use your thrust is just as important as how much you have. When I started out with this whole spaceplane thing I watched a Youtube tutorial where some guy used two Panthers and two Swivels for the same payload. His plane weighed somewhere just over 30 tons, I think. This thing weighs 15,186 kg on the runway and that's including 120 kg monopropellant that I really just should replace with regular fuel. That single Panther gets it to around 790m/s at 17500m, and from there the Terriers comfortably get it to an 80km orbit with around 250m/s dV to spare. Then you have another couple dozen m/s in the RCS thrusters but again, that's strictly worse as far as ISP goes and I should just replace it with regular fuel.

Other than the 1000 unit battery it's all stock parts that cost 160 science or less (battery could be trivially replaced by a payload bay and some smaller ones, plus a probe core or something). I also did use the configurable containers mod to muck around with LFO to liquid fuel proportions in regular liquid tanks and add a tiny bit of monopropellant so I could hide RCS thrusters under the nosecone and the Panther, but that's hardly mission critical - I just like getting really close before EVA'ing over. It could easily be made completely stock with no meaningful performance degradation.

It flies pretty well and reenters and lands at the KSC just fine, although the airbrake is overkill, really. The center of mass is essentially completely static during flight because the Terriers are mounted so far back, but I did discover after flying it last time that the tail cone mounting is definitely not as aerodynamically efficient as I thought it was when I built it. I should probably just extend the intake nacelles backwards with structural fuselages instead.

Edited January 14, 2017 by renhanxue

[ryan234abc]

Proof of concept: Can a Twin Boar be a part of an effective SSTO? Yes it can! 3 crew SSTO based around a Twin Boar!

About 1500m/s dV from LKO, or plenty of liquid fuel to take it for a buzz of the tower on re-entry!

Edited January 14, 2017 by ryan234abc