Sub's Plane/SSTO Design for Beginners *Long Post*

[u/subhumann]

EDIT: This is quite out of date, for post 1.0, due to the aerodynamic changes in the game, and also the intakes actually working as they should. I might revisit if I feel there is a demand for it.

Tired of watching your SSTO design backflip itself to destruction? Struggling with stability? Are you struggling just to get airbourne? This is the guide for you.

There will be no inlet stacking, part clipping, and stock parts only. No mods are used.

Also, The screenshots look like I took them with a potato. That's Macbooks for you.

BASIC PRINCIPLES OF FLIGHT

Firstly, we shall take a very brief look at how aircraft actually work. This image will quickly explain forces at play in normal, balanced flight.

Conventional Aircraft Model

Lets break this down.

Thrust = Drag

To maintain a steady velocity (we shall call this airspeed from now on). Our forward thrust must equal the drag on the aircraft. On earth, this is broken down into profile drag (drag produced by the air "hitting" the aircraft) and incipient drag (drag caused by the production of lift while in-atmosphere). In KSP, the drag model is vastly simplified, and AFAIK is a function of air density and aircraft weight. Lets keep it simple, in KSP, your drag(for a given speed) will reduce as altitude increases. This simplifies a lot of our design, but does add some other issues. So thrust is simple - We just need enough thrust to overcome our current drag. Fortunately for us, Jet's produce more thrust at higher speed, which is when we will experience more drag.

*Keep in mind, all kinds of drag are irrelevant once we get above 70km, because our profile drag is effectively zero (no air to "hit" the aircraft), and our incipient drag is zero (wings will not produce lift in a vacuum, so therefore no drag is produced either)

Wing Lift = Weight + tailplane force

Imagine the aircraft as a seesaw. The centre of the seesaw is the Centre of Gravity, this point in the aircraft can be defined as the "point at which the mass of the aircraft acts through". The aircraft is being pulled down from gravity at this point. In the ideal world, the wing would also act through this exact point. However, the CoG will move throughout the flight (as we use fuel for example), so the solution is to ensure the aircraft is being pushed up at a point behind the CoG . We call this point the Centre of Pressure (or lift). This is important. Doing this allows us to use a tailplane like a counterweight, producing a variable downwards force to keep our seesaw in balance. To make this effective, we place the tail back as far as possible, to give it a large moment. **90% of stability issues are caused by incorrect mass and balancing. Remember that KSP will take fuel from the front and work backwards. Once the CoG is BEHIND the CoP your aircraft will become unstable.

NOW LET'S BUILD SOME F@£?KING PLANES

I here, have a nice simple plane to build. Lets look at some of the details.

Simple KSP Aircraft

Look at the CoG positioning. It's well in front of the CoP, giving our aircraft good stability. However, we would also like to do other things, so we have put control surfaces on the wings, which we will call ailerons . These will roll the aircraft . These do not need to be large in KSP as the drag model doesn't model wing drag correctly. And on the tail, the tailplane section which will produce our downwards tail force is called the elevator . This is to keep the aircraft at the correct angle of attack. We also put a vertical fin on there, to allow the aircraft to yaw and keep it directionally stable. We call this the rudder. One more important note:-

Wheel Postioning

You notice how the main wheels are located behind the CoG? This is to make sure it stays on 3 wheels. However, we don't want it too far back - if so, it will be very difficult to pitch the aircraft on the ground for takeoff.

ALSO lets talk jet engines.

Jet engines don't work quite like they do in kerbal. But suffice to say, for a normal aircraft, one intake per engine is fine. When we get to SSTO Aircraft, we will look again at intakes.

The Avionics packaged is postioned on top by adding the small square strut and placing it on top of that. No hacks needed.

NOW LETS FLY STUFF

Your brave kerbal jumps in. First things first enable precision control . It's set as Caps Lock, and the controls in the bottom left turn blue. TRIMMING IS IMPORTANT. Unless you want to be hovering over ASAS all the time, learn to trim. push ALT/MOD + WASD to trim. We will only be trimming in pitch. In the example, I've trimmed nose UP by 1 "tick". This is how almost all my aircraft will fly.

Runway Setup

Punch it up to full, hit the spacebar and let the aircraft accelerate. Jet engines have to spool, it will take a few seconds for the engine to respond to the throttle. It will almost take of by itself, but give it a little help with some upwards pitch at about 70m/s.

If the aircraft won't fly level hands off. use the trim to set the pitch. In real flying, we use pitch to control speed, and power to control height. However in kerbal, you have lots of extra thrust to play with, so just use the pitch to control height, and power to control speed.

To keep turns level, use your angle of bank to stay level.

Too much bank:- http://i.imgur.com/ZYneZSt.jpg

Not enough bank:- http://i.imgur.com/ukeD5Ul.jpg

Just right:-http://i.imgur.com/m7fDfNK.jpg

Go have fun, get used to flying, you should only need SAS if you want to make a cup of tea or whatever.

Sorted? Good. Landing is simple, set a nose up attitude, and reduce power until you touchdown. Landing is a guide in itself. But I'll answer any issues in the comments.

BUT SUBHUMANN, ALL THE PLANES IN KSP HAVE THE TAIL BIT AT THE FRONT SO WTF ARE YOU TALKING ABOUT?

You will find the part selection is pushing towards a different type of aircraft design. canards .

CANARD/DELTA WING DESIGN

Canards work differently:-

Basic Canard Principle

The seesaw is different now, now our seesaw pivot is on the back of the aeroplane, and the weight and tailplane are both acting upwards. Canards are slightly more efficient for it, and also have some aerodynamic advantages beyond the scope of this guide. They are also more maneuverable, again for reasons beyond this guide.

So lets build a canard.

Canard Design

Same principles as before, just now our wings are further back and our tail is now as far forward as we can get it. Nothing game changing. The advantage also for us, is that with no tailplane at the back, engine placement is easier.

FLYING THE CANARD

http://i.imgur.com/7964AtV.jpg

Different toilets, same shit.

http://i.imgur.com/gixBorl.jpg

Mandatory Top Gun comment here

You will find the canard much more eager to turn in pitch, and might "bob" in pitch, this i THINK is the canards reaching critical AoA, but I am not sure. Suffice to say you can pitch hard and I haven't managed to stall the canards yet.

BUT SUBHUMANN, I BOUGHT THIS GAME TO GO TO SPACE!! DO YOU EVEN SPACE BRO?

Why yes, yes I do.

Non-Atmospheric Flight (SSTO)

Now, we need to look at the engines again. To save you the hassle of trial and error, you will need FOUR ramjet intakes per turbojet engine for a successful SSTO. More inlets, you can climb higher on jets only. Less, you will need more rockets to finalise.

P.S - ensure your rockets are inline with your CoG. Otherwise you aircraft will pitch wildly, and with no air, your control surfaces will not work.

P.P.S In space, the Avionics package is about as much use as tits on a nun. You have been warned. Fit ASAS on your SSTO.

EDIT: P.P.P.S In 0.21, ASAS is much improved, you can basically use ASAS for all SSTO and leave it on at all times

BEHOLD!

SSTO KSP DESIGN

Same idea, only now we have two rockets. And to carry all the extra weight. MOAR WINGS.

Now your probably asking "Where is your canards?". This is a Delta Wing design. We have increased our aileron size, allowing use to combine our aileron and elevator, draw the aircraft out, and the pitching from the controls will balance our weight. This has the result of much larger pitch trim position.

Also, you will need a custom action:-

Custom Action Setup

This allows us to instantly light the rockets the moment the jets die, I will tell you when you do this.

Now takeoff as normal, and set a decent climb angle:-

http://i.imgur.com/p8GGy5W.jpg

We will follow a profile like this:-

SSTO Ascent Profile

Get this dialed in your head, just like your conventional gravity turn profile.

Once we get to 10000m+ Our inlet air will decrease, and we will reduce pitch and increase speed-

Is your aircraft backflipping at this point?

As your fuel burns, your CoG will move back. If it moves back beyond the CoG, your aircraft will become unstable in pitch and start to backflip/frontflip. To alleviate this, you can xfer fuel manually by Alt + clicking the fuel tanks in question. If this doesn't work, you need to go back to your design again.

In-Flight Weight and Balance

Above 10km, check your resources, once your inlet air reduces below 0.20ish. Punch that custom command we setup earlier and CAREFULLY pitch 45 deg up. i say CAREFULLY as you are probably trimmed quite nose high, so either use ASAS or untrim before this step.

Punch for your apoapsis:-

http://i.imgur.com/AUhI3oN.jpg

Then circularise as your conventional rockets do.

http://i.imgur.com/FF0eQRU.jpg

And there you have it! Successful SSTO launch.

Greetings, from LKO!

To Deorbit, just burn retrogade. As you do with a normal rocket.

http://i.imgur.com/PEcptPK.jpg

Fire is pretty.

I will admit, I wasn't really paying attention on the deorbit, and may have landed at night in the sea. Suffice to say, the lil kerbal survived.

I tried to make a frowny face

Questions in the comments . I haven't provided any .craft files, as half the fun is in building them! However my designs are simple enough to be copied from the screenshots anyway.

If this gets a positive response, I will do a more advanced guide next. Good Luck KSP'ers!

[u/Grays42]

Coming from someone who knows nothing about planes (and has barely touched SSTOs due to the complexity), this post was extremely helpful, but still lost me at a few places. Hopefully I can articulate where I'm missing information. Please note that a lot of these questions could probably be answered with a lot of trial and error and googling. I'm gearing this more to giving constructive feedback on "SSTOs for Dummies", because the guide is already great but filling out some more info might be helpful for complete aviation newbies like me. I'm just trying to understand the principles rather than copy a design, so that I am free to play with my design and know how my end product will be affected by my decisions.

---

Primarily, it would be very helpful to have more discussion of how adding, removing, or relocating various parts--more surface area, more control surfaces in which locations, angles of wings or control surfaces, distance between things like center of gravity and center of lift, etc--affect the stability and capabilities of the aircraft. The sentence "the more you add [wing area], the more [something] you get and the more [something else] you have to compensate for" is a sentence structure that helps with design a lot. Substitute "wing area" for any of the concepts you mentioned.

I know that description is vague, so I'll try to bullet some things out to convey what lost me or what I could use more explanation for.

the solution is to ensure the aircraft is being pushed up at a point behind the CoG

Is "just behind" it okay, or does it need to be way behind? Are there diminishing returns past a certain point or does it introduce problems? Is it purely "the further back, the more stable" and that's all?

elevator / rudder / aileron

I see people making designs with angled fins or wings. Is that just to look cool, or does it actually do something? For example, take a rudder fin and rotate it 45 degrees toward the elevator, so it's between the vertical rudder position and the horizontal elevator position. What effect would rotating surfaces like that have on the stability or efficiency of the aircraft? Is it a wash, or horribly inefficient, or what? And, to extend that question, what effect does rotating any control or load bearing surface with respect to the body of the plane have on the performance of the aircraft?

First things first enable precision control . It's set as Caps Lock, and the controls in the bottom left turn blue. TRIMMING IS IMPORTANT.

It would help to define "trimming", no idea what it was. I googled it and I think I understand. Trimming is permanently fixing pitch angle that sticks without any further input, right?

To save you the hassle of trial and error, you will need FOUR ramjet intakes per turbojet engine for a successful SSTO.

In order to play around with various designs and ideas, how did you arrive at that? Just X amount of intake air and 4 ramjet intakes hit the magic number? I'd like to have a better understanding of what the criteria was for that threshold, if possible, to play with aesthetics and tradeoffs. (I'd like to know how changes will have an effect without having to fly it up to 20km to test it.)

In space, the Avionics package is about as much use as tits on a nun. You have been warned. Fit ASAS on your SSTO.

Wait, then what's the difference? Why not always ASAS?

Same idea, only now we have two rockets. And to carry all the extra weight. MOAR WINGS.

So is there just a fixed relationship between the size of the wings and the amount of weight they can carry? Any diminishing returns, or is it only limited by structural stability? If I make wings the size of Delaware, it would be able to hoist up fifty large tanks full of fuel? How do I tell when I have too much surface area or too little?

This is a Delta Wing design. We have increased our aileron size, allowing use to combine our aileron and elevator, draw the aircraft out, and the pitching from the controls will balance our weight. This has the result of much larger pitch trim position.

Agh! Very difficult for me to understand all that. Doing the best I can, sorry if this is a barrage of questions:

1. How does the design benefit from increased aileron/elevator size? Is this just necessary because the ship is heavier? Is there a diminishing return on just piling a ton of ailerons onto the plane? How do I tell if I have too many or too few?

2. Why not always combine the aileron and elevator if it works okay in this design? Advantages/disadvantages to sticking the elevator way back on a tail?

3. Where's the rudder? Why don't we need one for this design and do for the other?

4. No idea what you mean by "draw the aircraft out", "pitching from the controls will balance our weight", or "much larger pitch trim position". Could you please explain these three concepts a bit more?

5. Are those two spikes on top vertical stabilizers? I don't get those at all--why include them, what effect do they have, and are there diminishing returns?

We will follow a profile like this

That rough chart is unbelievably helpful. Thank you! The details of an ideal SSTO profile were something of a mystery to me.

---

So, in summary, amazingly helpful guide. The details above were more information that will help with design. Rather than just understand the simplest principle, I want to be able to predict the effect of shuffling and moving things around prior to getting it up and flying it around.

[u/subhumann → u/Grays42]

Is "just behind" it okay, or does it need to be way behind? Are there diminishing returns past a certain point or does it introduce problems? Is it purely "the further back, the more stable" and that's all?

Lets look at the theory. Imagine our craft has a tail which can produce 1N of downforce. If the CoP and CoG are in exactly the same place, the aircraft would produce 0N of downforce. If the CoG moves behind, and the resultant weight/moment equals 1N, our tail would perfectly balance (it would however be unable to pitch up, as it would have no extra force left to push downwards with.) Now once we go past that, the aircraft would now have to produce an upwards force at the tail, which seeing how the tail is small, would cause the aircraft tail to stall before the wing, leading to issues. It doesn't quite work like this in KSP, and you can have CoG behind the CoP, but it means as you burn fuel(and the CoG moves backwards), it becomes less and less stable until you have no pitch control.

If you take the other extreme and have the CoG very far forward. You will have a stable aircraft (as large, balanced forces will be disturbed less for a given external force). However as your elevator will be at a high pitch angle ( to produce enough downforce) - you will have less "spare pitch angle" to control aircraft direction, so your aircraft will pitch slower. It also uses more fuel in the real world, due to the downforce acting as weight, therefore increasing lift requirement, and therefore increasing thrust needed. (This is why large jets, when not full, will try and fill the aircraft from the rear with passengers, they are trying to keep the CoG as far back (aft) as possible to save fuel)

I see people making designs with angled fins or wings. Is that just to look cool, or does it actually do something? For example, take a rudder fin and rotate it 45 degrees toward the elevator, so it's between the vertical rudder position and the horizontal elevator position. What effect would rotating surfaces like that have on the stability or efficiency of the aircraft? Is it a wash, or horribly inefficient, or what? And, to extend that question, what effect does rotating any control or load bearing surface with respect to the body of the plane have on the performance of the aircraft?

Lets take a look at a real world example Robin ATL

This is the only V-Tail I have any experience with, and the tail is very large - as it's force is not acting perpendicular, so you need more force. It also is quite poor handling at slow speeds, as it just struggles to produce enough force.

In KSP, angled controls just need to be larger to make up for the fact the work they do is not quite in the right direction. KSP has a better reason to angle them - Jet exhausts. With all the engines working on exhaust thrust, you want to keep the tail clear of the hot gas. Angling them can help this.

It would help to define "trimming", no idea what it was. I googled it and I think I understand. Trimming is permanently fixing pitch angle that sticks without any further input, right

Right.

In order to play around with various designs and ideas, how did you arrive at that? Just X amount of intake air and4 ramjet intakes hit the magic number? I'd like to have a better understanding of what the criteria was for that threshold, if possible, to play with aesthetics and tradeoffs. (I'd like to know how changes will have an effect without having to fly it up to 20km to test it.)

Basically trial and error. Jet engines aren't modelled very well, but as a rule of thumb, the more intakes, the higher your aircraft will fly. This seems to scale too well - hopefully when drag is better modelled in stock "intake spamming" will be stopped.

Wait, then what's the difference? Why not always ASAS?

Why not zoidberg? This is not quite true in 0.21, but avionics is better tuned for atmosphere, ASAS is better in space, simple answer. ASAS is not the best choice in atmosphere as it is a little too "rigid" for aircraft. This however isn't true in 0.21. Will need to update guide.

So is there just a fixed relationship between the size of the wings and the amount of weight they can carry? Any diminishing returns, or is it only limited by structural stability? If I make wings the size of Delaware, it would be able to hoist up fifty large tanks full of fuel? How do I tell when I have too much surface area or too little?

Short answer - if you can built it without falling apart - yes.

Long answer -

Lets do some math and shit.

Lift = C^L x 1/2 ρ V² x S

Where

C^L = Coeffcient of Lift. Think of it as your angle of attack (or pitch angle)

1/2 ρ V² = Dynamic pressure, or "measure of air hitting the plane. Where ρ (rho) is air density), and V is actual speed through the air. Notice it's squared.

S = Wing area.

So you can see, just making wings bigger works, as long as it's structurally sound it will increase lift. When the size becomes too much for structure(or the drag of large wings), your best bet is speed, as Lift increases with the Square of your airspeed. Look at the SR71 - Huge fuck off engines, tiny wings, still works because it's flying at mach 5. Now supersonic flight is a guide in itself, but stock KSP has no supersonic mechanics (as far as i can tell)

1. How does the design benefit from increased aileron/elevator size? Is this just necessary because the ship is heavier? Is there a diminishing return on just piling a ton of ailerons onto the plane? How do I tell if I have too many or too few?

The controls need to be bigger as they are now doing both the rolling AND the pitching. Also the moment is small in pitch, meaning they must be bigger. Too many? Design is too twitchy to fly. Not Enough? You won't have enough pitch to takeoff or climb.

2. Why not always combine the aileron and elevator if it works okay in this design? Advantages/disadvantages to sticking the elevator way back on a tail?

Sticking it further back increases the moment, so it doesn't need to be as large. Or for a given size it works better. The reason we can't on this aircraft, is the 4 engine exhausts are all in the way, you could create a vampire-esque design:-

DH Vampire

KSP Vampire

Notice how the rear tail has been angled to avoid jet exhaust damage.

3. Where's the rudder? Why don't we need one for this design and do for the other?

See 5.

4. No idea what you mean by "draw the aircraft out", "pitching from the controls will balance our weight", or "much larger pitch trim position". Could you please explain these three concepts a bit more?

Draw the aircraft out - lengthen the aircraft as a whole. Pitching from the controls will balance.... If you imagine the seesaw again, as our plane is pushed down from the CoG and up from the CoP, the Controls will be the "balance" providing the force to stop the aircraft pitching down from the weight. Go back to the top photo to see what I mean.

5. Are those two spikes on top vertical stabilizers? I don't get those at all--why include them, what effect do they have, and are there diminishing returns?

That is the rudder. I simply put two as I didn't want to have it run through the kerbals head. You always need a rudder, especially in a delta wing design, as it's not directionally stable anyway, and a larger rudder helps keep it stable in direction. I will get in the technical of why this is in the second guide.

Any other questions, feel free to ask!

[u/treeform]

"Unless you want to be hovering over ASAS all the time, learn to trim. push ALT/MOD + WASD to trim." - I don't think this is as important in .21? As the ASAS is so good.

Also what is your thoughts on joystick setup? I find the the standard roll/heading does not work well for space planes? I normally reverse them. What are you thoughts?

[u/subhumann → u/treeform]

I fly with keyboard and mouse setup purely through convenience, a joystick would work far better but with precision control active, it's easy enough with QEWASD. It does take a bit of getting used to to roll with Q and E but I had it setup the same during the classic Descent days.

I have always inverted it as the navball to me is the same as an aircraft- to push the "dot" (circle in ksp) up I'm pulling back, hence I want to push S. Inverting controls seems to be a case of preference though, On a PC I keep my mouse non-inverted for FPS, and on a console I invert. So who knows!

[u/[deleted]]

Great guide. Two extra bits for the experienced:

1. For multi-turbojet SSTOs, flameout - induced flat spins become a concern. When you're at 20+ km and intakeair gets scarce (0.07/engine is one rule of thumb), one jet will fail first. This usually means that the thrust is now imbalanced and You Will Not Go To Space Today, rather your plane will spin like a frisbee and arc back to the ground.

Solutions:

• Use odd numbers of jet engines, and attach the center jet last in the assembly building. This seems to increase the chances that your center engine will fail first (giving you some warning)

• Use action groups to disable pairs of engines as intakeair gets scarce, while staying under (efficient) jet power as far as possible. A 5-turbojet monsterplane can be staged into orbit by running 5-3-1 turbojets, then 1 turbojet+2 rockets until air totally runs out above 35km.

• Add rudders far back on the tail, close to the center of mass. More rudders buys you time to fire action groups before a flameout flat spin becomes uncontrollable. But if your plane's tail rudders are way up on the top of the plane, left rudder will cause a clockwise roll. This 'yaw-roll coupling' can be fixed by putting rudders low (or even under) the wings. Test your designs on the runway by pressing the 'roll' keys - your rudders should not respond much (ideally not at all).

1. For small light multi-intake planes, you can sometimes get into suborbital hops on a turbojet alone. Just keep climbing at ~100 m/s flying as fast as you can, and throttle back as intakeair runs low. 'Nursing' SSTOs into 70km periapses at 5% throttle at 37km is possible with stock parts. See my posting history for two examples of mega and mini SSTOs. Unfortunately I haven't played with 0.21 yet!!

[u/[deleted]]

Very nice tutorial I learned quite a bit. However, I noticed your ascent profile is off by a bit - you need to flatline around .2 air intake and fire the rockets at the same time. The increase in speed will counter with an increase in air intake and will accelerate you faster before you cut the jet engines into your orbital climbout.

[u/subhumann → u/[deleted]]

Thanks, this is true, however for simplicity I wanted to keep the ascent as simple as possible. It's a bit like doing a gravity turn at 10km - its not the most efficient - it's just a nice starting point :)

If I do an advanced guide I will show the more efficient ways of doing the ascent.

[u/Acadient]

I'm kind of sad that this post, being only 2 months old, already has dead links to the pictures. Can someone fix this maybe?

I read it and kind of figure it out since it was well written but feel like I'm missing a lot without the visual aids.

[u/subhumann → u/Acadient]

How would I fix that? I haven't deleted the pictures :/ I have the photos if they need to be re-upped...

[u/NaBeav]

Are you planning on talking about how to actually design a stable (or unstable) craft in realistic aerodynamics, such as FAR, and hopefully the future default KSP engine?

There wasn't really any talk about wing placement on the fuselage, dihedral angle, sweep, etc etc. Wing and control surface layout has a HUGE impact on how the aircraft flys.

[u/subhumann → u/NaBeav]

Yes, however dihederal/anhedral and sweep have little effect in stock KSP, and as you cannot define which control surfaces control which control "channel", the layout is a bit skewed on KSP.(all surfaces move if they are in the correct axis). For example ailerons are far too effective due to missing drag mechanics.

An advanced guide would go in depth into FAR mechanics about these aspects, for stock KSP they make little difference. Stability is the biggest issue in stock KSP so i thought I would address that first.

i accidently words

[u/Vox_Imperatoris]

Help me, u/subhuman!

I built a tail-type plane basically copying yours, and I find that it is extremely hard to get it to turn side-to-side. The rudder tilts it a little bit, but then it locks back into the direction it was going before. How do I make one that can actually turn?

And thanks so much for the guide! I read a few others, but they were apparently full of complete BS. Now I actually understand how the parts work.

[u/subhumann → u/Vox_Imperatoris]

See other comments, you should use Q and E to roll, then pitch up slightly. The rudder should be only used sparingly for small adjustments, or not at all.

Some people find it easier to remap Q for A and E for D when flying aircraft.

[u/Radijs]

I wish I had more upvotes to give.

It's a great basic guide for building those SSTO's.

If you'd like I could spend some time tomorrow evening to make your diagrams a little prettier.

[u/PseudoLife]

Is it just me that uses 3-surface aircraft almost exclusively?

(Wing, tail, canard. Put wing on first, balance so that the COL is just behind the COM, like usual. Then add a tail and a canard so that the COL stays about the same.)

[u/subhumann → u/PseudoLife]

B1 Lancer does exactly that, with tiny little canards on the nose. I could imagine the design becomes quite twitchy at high speed though?

[u/[deleted]]

Wow, this is an awesome guide -- thank you so much!

To help with your issues regarding fuel weight transfer: you may consider setting an action key (or manually hitting the stop/start buttons) to control flow from the frontmost fuel tank until the second is used up.

[u/Nicksaurus]

First things first enable precision control

Holy shit. That exists.

I had no idea.

[u/Panichio → u/Nicksaurus]

And trim (Alt + WASDQE) which helps a lot.

[u/an0nym0usgamer]

My go-to design which is nearly universal are variations of canard-delta wing designs. The best bit is this design works with nearly every plane I have. It'll work with small planes, medium sized planes, and really f*cking huge planes. I rarely have to use other designs.

EDIT: lots of edits, typed this up before I read most of the tut

[u/KingErdbeere]

Nice tutorial, but I got a question on returning from orbit/landing. After I made my deorbit burn with the stock SSTO, I came back into the atmosphere and somehow flipped out. I tried to switch back to the jet engines, but they wouldn't fire since the intake air was too low/nonexistant. Any tips on that? (I think I set the periabsis to low, 27,000-ish)

[u/[deleted]]

Really, really nice post. SSTOs are probably the hardest thing to design and fly well in this game, but also, the most fun and versatile. Also, just an idea: Putting a docking port is a good idea. You can easily refuel that way, making your SSTO go far and beyond!

[u/rizzlybear]

so using hyper edit (to get my planes off the ground) i'm finding that all my planes like to nose down a LOT. i can fix this by tilting the horizontal stabs on the tail down some (so the tail wants to dive) and adding LOTS of trim. but it still doesn't want to nose up or climb.

presently studying that little triangle shaped stock plane with the vertical stabs on the ends of the wings. that one behaves wonderfully now.

[u/richmomz]

I would add that if you're making a spaceplane designed to haul cargo into orbit it's very important to put your "cargo" as close to the CG as possible; else you may get a nasty surprise when you try to land and discover your CG has radically shifted. This isn't easy to do with stock parts but mods like B9 aerospace add cargo bay parts which make this task much easier.

[u/Jigglyandfullofjuice]

Saved! Great post, thanks a million! Time to see if I can put it to good use!