I keep quitting because of this one single reason.

[Dragonchampion]

On the TWR: once you are in orbit (= no longer investing power to prevent falling into the ground) and out of an atmosphere, you can easily get away with less TWR than 1. This will just require longer burn times.

What about in Duna and Eve? And any other planets or moons? Is there a specific TWR that you need in order to take off from them? I know Kerbin is 1.0, but what about Eve, which is thicker than kerbin, or Duna which is thinner?

[Wanderfound]

What about in Duna and Eve? And any other planets or moons? Is there a specific TWR that you need in order to take off from them? I know Kerbin is 1.0, but what about Eve, which is thicker than kerbin, or Duna which is thinner?

You can get a medium size Mk 2 spaceplane back off Duna with just a nuke or two for thrust (see my vids posted upthread for a demonstration). You'll need a longer than usual takeoff run, but that's not a problem when you've got an entire planet to use as your runway. Laythe is easier, due to the ability to use jets; if it'll fly to orbit on Kerbin, it'll do it on Laythe.

As for Eve, forget about it. Unless you're using some sort of near-infinite fuel mod (like the fusion plants Scott Manley used in his last series), you won't be getting a spaceplane back from there; the ÃŽâ€V requirements are just too high.

[n.b.z.]

I'm not really that experienced a player, but the general answer would be: yes, each body requires a specific TWR; the higher the gravity, the more thrust you need to lift off, and also the more delta-V you need to attain orbital speed.

Look at the wiki, it lists the "surface gravity" of each body in the system. This gives a rough idea of how your destination relates to Kerbin. Each page about every body has a box with this (and many other) data.

http://wiki.kerbalspaceprogram.com/wiki/Category:Celestials

Thickness of the atmosphere is a consideration on top of gravity: air slows you down, so you must burn longer (= more delta-V) but it might also help to have a bit more thrust to get out of the air quicker.

I recommend to stay away from Eve, unless you just want to drop a probe that you will never get back. Eve, in addition to having stupidly high gravity, has The Worst atmosphere. Which means you will need a crazy high TWR, and keep this TWR running for a LONG time. Returning just one Kerbal from that place is among the most difficult things you can do in this game.

(I would welcome to be corrected by more experienced players.)

EDIT: my TWR answer was more general, not really plane-specific. I think for planes, just attaining Kerbin orbit first, and coming back in one piece should be the focus. Going interplanetary works (see the expert on that above) but you are carrying jet engines, wings and other atmosphere-related stuff you may not actually want to drag through the system.

Edited April 24, 2015 by n.b.z.

[Wanderfound]

I'm not really that experienced a player, but the general answer would be: yes, each body requires a specific TWR; the higher the gravity, the more thrust you need to lift off, and also the more delta-V you need to attain orbital speed.

The one addendum to that is related to wings. If the planet has atmosphere, you can get to orbit with a TWR much less than one; the wings do the lifting while the thrust is devoted to increasing horizontal speed, same as on Kerbin.

[panzer1b]

Im the opposite of you lawl.

i NEVER EVER EVER make rockets nor am any good with rockets, and every single thing that isnt a capital ship (and hyperedited to LKO anyways) is a SSTO or a aircraft styled ship. I dont know why but i never liked making pure rockets, big tall cilinders are way less cool looking then jet fighters, interplanetary bombers, and the like.

Anyways, there are some tutorials out there (google ksp SSTO tutorial, there are both thread and videos out there). It all comes down to making it balanced especially when fuel load changes. Aside from making it stable, there isnt much to making a aircraft that flies and goes to space. just strap enough jets to get off teh ground, and a small rocket with some rocket fuel (or use monoprop engines like many do) to get into LKO.

[Redshift OTF]

I made a VTOL SSTO that can get an orange tank into orbit.

And a mk3 Skylon.

So I think SSTO's can be cool and useful sometimes. I usually use 1 jet engine per 10 tons and go as fast as I can horizontally until the air drag slows me down and then climb 100m/s so my increase in speed is due to the air getting thinner and then I know I am at a decent speed when the air is so thin that my jets start dying out.

I've also made an SSTO that can get to Laythe and back.

[hazard-ish]

I wouldn't worry about it too much. I've been playing the game since version 0.19-ish and only got my first SSTO to work in version 0.90!

However, if you're really insistent on getting one to work I would highly recommend checking out some YouTube videos of people flying because they can be much more helpful than static images.

Here are some links to great SSTO showcase channels that really helped me design a working space-plane!

https://www.youtube.com/user/MrOverfloater

https://www.youtube.com/channel/UC0ZvL1WjqSwp_8QmIlNgRog

Hope that helped!

Edited April 24, 2015 by hazard-ish

[Octa]

I can fully understand the. I had my first design with about 30 more or less small changes until i got this damn thing in an orbit. I got into orbit before, but with almost no fuel left, so not very useful. The last design can do some usefull stuff in LKO and has enought liquid fuel left to avoid a pin point gliding to KSC.

Seriously, it was a pain in the arse, but i thought "C'mon, there's so much crazy stuff in the forums that can fly into orbit, there's not much left that mine will too". That's why i registered here. And i found that flying a ssto right is way harder that building it.

You guys gave me one small tip that made the difference: Throttling down. o.O

I found that the actual challenge is to keep the flight parameters in balance. The throttle is way better to fine control the vertical speed of the craft than changing the pitch angle. With this i was able to build up way more speed, because i kept the vertical speed low enough to still have intake air. The increasing horizontal speed at same height compensates the lack of air.

After a while, the lift of the wings increased because the speed increased. Therefore, i throttled down further to avoid ascending too fast. At some point, the craft starts to lose horizontal speed because of the low throttle. I lowered the pitch to reduce the lift and throttled up again. Then i repeat controlling the vertical speed with the throttle until the next pitch change is necessary.

It just how an autopilot works IRL, all parameters influence each other. Fixed thrust at fixed height -> fixed speed. Plane gets lighter because of fuel consumption -> more speed -> lift increases -> height increases. So the autopilot needs to pitch down and/or reduce the thrust. In KSP, the player needs to do that manually.

Personnally, i recommend 2 mods for SSTOs:

- AirIntake Building Aid: My design has 2 Jets, this mod makes it much easier to assign the intakes to the engines evenly to prevent assymetric flame-outs

- Mechjeb: 1: Info-Window for horizontal and vertical speed, 2: i use smartASS to fix heading and pitch angle, so i can focus on other things. If i need to adjust the pitch, i can change the angle very accurate by a few degrees, hit execute and continue.

"Just" this small hint and i was able to get a speed of 2000m/s somewhere between 25 and 30 km, something i never managed to do before.

[Captain H@dock]

Landing a SSTO spaceplane? This is why I finally gave up. What a colossal pain in the keister. I killed so much time (and so many Kerbals) it just wasn't worth it anymore. I went out and bought a joystick for crying out loud, because everyone was saying, "It's so much easier with a joystick." No, it really isn't.

To land, you must be slow. Touching down above 70 m/s is always going to be much more dangerous than around 40 m/s. So you must make sure you design can actually land (when empty) at slow speed with a reasonable AoA (to prevent tail-strike). From there, the joystick won't make much of a difference since you can use SAS to hold your pitch angle until touch down.

But really, you should focus on approaching low, shedding more speed over the runway, and stay in the air as long as possible in order to touch down as slow as possible.

Edit: I totally agree on the throttle down tip. Throttle down before flameout. This will make the difference between flaming out at 33K and flaming out at 48K.

SSTO planes are really just about flying profile, and I've found screenshot don't really convey that. What we'd need is a black box mod so that player could just share they profile traces, and we could more easily teach/learn from each others.

Edited April 24, 2015 by Captain H@dock