Why should i use spaceplanes?

[Little Green Mensch]

Rockets are definitely faster, but the challenge of designing a spaceplane is fun, and they look nifty in orbit. I'm not sure how much of a cost difference there is, but being able to land at KSC with all (or most) of your parts is helpful in career mode, and, for recovery missions, a great big cargo bay that can land on the runway is pretty handy, too.

Insofar as spaceplanes are "cheating"... Kerbin is an impossibly tiny planet peopled by large-headed, bulgy-eyed, green-skinned pyromaniacs who all live on the same equatorial peninsula, for some reason. Like rockets in KSP, spaceplanes have a high dry weight and use engines which would be woefully underpowered for the real world. They're certainly not playing the game on easy mode, and, if you use FAR, you gain a couple more layers of challenge from aerodynamic disassembly and mach effects.

Also, even in the real world, people haven't given up on spaceplanes. The RAPIER is based on a real-world concept, after all, and the U.S. Air Force is still playing around with the X-37.

[Phil deCube]

What is the benefit of spaceplanes in KSP?

You feel great the first time you get it to work and thats it.

It takes much more time to reach LKO.

It has got very limited payload.

And for the mechjebbers - you can´t use MJ to launch.

So why would i use spaceplanes?

I don't. I haven't since about version 0.24. I don't see the point either. In fact, I don't even update the SPH or the runway until I have completed the tech tree and amassed a few million Kerbal Bucks. Some people say they are good for re-usability. I just install the Stage Recovery mod, which gives you Bucks back for stages with enough parachutes on them to land safely (it will also land them under propulsion, if you give the stage a probe core). In my opinion, which is worth as much as you paid for it, far too much effort is spent on spaceplane development, compared to "proper" spacecraft. Let the howling commence...

[NoMrBond]

Deployment cost for an SSTO is high but the recovery fraction can be almost 100% since the only thing being expended is the fuel

This may float your boat, tickle your fancy, play nicely with your mod/s of choice, or simply provide a satisfying challenge

[Clipperride]

The only reason I can think of is the fun of the challenge. They are ridiculously more difficult to get right compared to rockets. You can make one apparently minor change to a space plane and it goes from perfectly flyable to crashing off the runway as the gear gives way beneath it. Simply strapping on more engines is rarely the solution either. On the other hand, the first stage of your rocket is a little sluggish of the pad now you've tweaked an upper stage? Attach the right sized SRB and your away

For me, if I want to get something done I go to the VAB every time.

Edited September 21, 2015 by Clipperride

[Nothalogh]

What is the benefit of spaceplanes in KSP?

You feel great the first time you get it to work and thats it.

It takes much more time to reach LKO.

It has got very limited payload.

And for the mechjebbers - you can´t use MJ to launch.

So why would i use spaceplanes?

Why- The glory of hypersonic flight to orbit

Mechjeb- I use Maneuver Planner all the time

Time- The most time that is spent is on the coast out of the upper atmosphere on the transfer orbit to desired orbit, and that is easily timewarped, I'm usually six minutes from runway to the transfer orbit

[Vegetal]

This again?

If you really want to be economic, they are the way to go, but if you get bored easily, they are not.

I'm a pilot, I like planes and helicopters and spaceships, so I like spaceplanes. There. This endless discussion of which is better is utterly pointless.

[GoSlash27]

If you want to transport Kerbals and supplies to a station in LKO as cheaply and safely as possible, SSTO spaceplanes are the best way to do it. If these aren't your priorities than there's no reason for you to use them.

Best,

-Slashy

[MacGamer04]

While I'm still not the best space-capable plane designer, I've designed many atmo-only aircraft that are fun to fly on my casual KSP time (I call it kerbalnaut flight training, lol). But the reason I build atmo-craft in career mode is to accomplish science & survey contracts on Kerbin. It's a technique to build some funds, science and rep without having to go into orbit. That way you can get a few more nodes available on the tech tree before going to the Mun or Minmus for example.

This Su-33 analogue for example is very fun to fly. It can takeoff and land in a short distance, can fly high and fast, and still rock solid stable in high-G flight.

http://i1356.photobucket.com/albums/q737/raptor_9000/Placeholder%20Photos/SPH%20Showcase/X-8%20Blended%20Fuselage-Wing%20Flight%20Test_zpskqn4fflf.jpg

Hey, can I get the craft file for that?

[FungusForge]

I've had spaceplanes that could outlast some of my rockets, and seen spaceplanes that could carry more than all but one of my rockets.

However the advantage is always centered at Kerbin. Spaceplanes at Laythe are almost invaluable, because between the near-Kerbin environment and the tiny land masses, having something that can redirect your landing alone is pretty great. And if only landing with the payload is necessary, then the spaceplane can land something heavier than what it can lift.

Spaceplanes have their own place, and rockets as well. To a degree these overlap, and where they do its only a matter of preference.

[Voculus]

Why build spaceplanes? It's the journey, not the destination. Any Joe Blow off the streets can stack fuel tanks on top of each other, like a toddler stacking wooden blocks, and then let Mechjeb fly it to orbit.

It takes practice and experimentation to make efficient and reliable rockets, and much more so for a 100% reusable spaceplane, particularly when they're designed to travel to other planets and back. In my mind, there's no effort more rewarding in all of KSP.

Edited September 21, 2015 by Voculus

[Val]

... spaceplanes don't exist in real world ...

In my opinion, if it was as easy to launch SSTO spaceplanes from Earth, as it is from Kerbin, then they probably would exist in real life, too. So I see no problem having them on stock Kerbin. BTW, the Space Shuttle was a spaceplane, but not an SSTO.

In theory, yes. In practice, rockets can lift much larger payloads, regardless of player skill or the amount of design effort.

For example, a simple stock rocket that takes 10 minutes to build can lift ~450 tonnes to LKO. How long does it take to design a spaceplane to lift that much payload? And how large stock rocket one could build in that amount of time?

I think, one of the reasons these two statements are true, is because rockets have much larger engines available. With RAPIERs it is not feasible to lift more than 25-30 t per engine. The part count to make a spaceplane capable of lifting 450 t cargo, would be a performance killer, but not impossible.

I've made stock SSTO Spaceplanes that lift just over a 100 t with under 100 parts, but I didn't put RCS or external docking ports on it. And I have a WIP one that can take payloads up to 7.5 m in diameter.

But you're absolutely right. They take a lot of time to design. But that's the part of KSP I like the most.

[Red Iron Crown]

Use spaceplanes if you enjoy building and flying them. Use rockets if you like building and flying them better. It's not really more complicated than that.

Sure, there are economic benefits to SSTO spaceplanes and there are time benefits to using rockets (both in time-to-orbit and design time), but those aren't all that important. Career mode pays enough that you don't really need the economic advantage of spaceplanes, and the reduced time for rockets is no advantage if you enjoy flying and building planes.

[Vegetal]

Interesting plane there Val, how do you connect the fore and aft parts?

[Val]

Interesting plane there Val, how do you connect the fore and aft parts?

The payload connects the 2 parts, which of course imposes some limitations. Strutting the cargo is needed to stop wobble.

The 2 halves, can land and launch as separate crafts or docked together. Been able to lift up to 72 t with it. That limit is imposed solely, by the positioning of the landing gear. If I could get a set of landing gear right underneath CoM, then it should theoretically be able to launch with around 120-140 t cargo. Would need more fuel also. Max take-off weight will be around 400 t. Current version has a max of 300 t.

Edited September 21, 2015 by Val

[Warzouz]

Nice plane !

[xebx]

Spaceplanes don't exist in real life, so they are very optional in KSP if you are interested in Science not SciFi, from here economical benefits of highly hypothetical unrealistic spaceplanes are non-sense.

I'll add to this : nuclear spaceplanes are extreme non-sense.

It's a game you can go SciFi or Science, where you have fun.

The shuttle was not a spaceplane but a winged rocket using big big boosters like all rockets. I was very popular and a big economical failure at same time, that's why it was stopped.

99% payload launches to LEO are rockets.

Skylon is a joke, a fat sausage without wings or real bodylift or big engines. Virgin airlaunch is a joke. Real stuff are named Delta IV, Ariane V, Proton, Soyouz, SpaceX, etc

[Van Disaster]

Spaceplanes aren't an IRL thing yet because earth is so large. If Kerbin was as large then we'd not be using them there either - have you tried building a useful spaceplane in RSS? the shuttle was only vaguely a plane, it's aerodynamics were an atrocity - just good enough to recover it.

Economic reason for SSTO spaceplane - 100% recovery. To be fair that's also a reason for a SSTO recoverable rocket, it doesn't have to launch horizontally. Using a plane means higher payload ratio though. I've no idea what you can get to orbit in stock aero, but under FAR you could get to orbit with a TWR of under 0.3

[tseitsei]

Hmmm...

@ OP

When you have a rocket lifter that has 30+% payload fraction and is completely reusable and can consistently land on the KSC runway give me a call.

That's why we use spaceplanes. They are cheaper in KSP than vertical lifters. The launch cost is only the cost of fuel (since you get 100% refund from ALL of the parts) and we can use efficient jet engines most of the time we are flying. For rockets launch cost is cost of fuel AND some percentage of the part prices that you lose because you can't (consistently) land on the runway...

[Val]

Whether it was an economical failure or the aerodynamics were atrocious, does not affect the Space Shuttle's status as a spaceplane.

A spaceplane is an aerospace vehicle that operates as an aircraft in Earth's atmosphere, as well as a spacecraft when it is in space.

...

Only five spaceplanes have successfully flown to date, having reentered Earth's atmosphere, returned to Earth, and safely landed  the North American X-15, Space Shuttle, Buran, SpaceShipOne, and Boeing X-37.

Source

According to the official definition of spaceplanes, they do exist.

And BTW, IRL unwinged pure rocket SSTOs have never flown successfully, either, unless you count Apollo landers reaching orbit from the surface of the moon. Should rocket SSTOs be scoffed at in KSP, too?

[xebx]

5 spaceplanes, how many rockets were launched ? ratio must be 0.001% that's why i say they don't exist/ are very optional (economical failures etc, X37 is very special it's a military recoverable spacedrone)

Skylon project started in the 80's, it's dead, except maybe the engines, maybe Roll Royce (the real top guys no jokers) are lurking behind hoping something good and dropping some money into.

Flying jokes are a good way to have fun, it makes me think of space balls or laythe ssto challenge, so hilarious spaceplanes airbreathing on another planet (80% nitrogen and 20% oxygen atmo, how hyperlucky) and using nuclear rocketry. Absurdity

Edited September 21, 2015 by xebx

[Red Iron Crown]

You don't like spaceplanes, we get it. The thread is about why *should* one use spaceplanes, not why one *shouldn't* use them.

[Beachernaut]

I find pure entertainment in the fact that someone says I'm wrong because my play style is different from theirs.

[xebx]

Ok i am lacking precision : in real world :

SSTO spaceplanes don't exist

Spaceplanes were a big economical failure (you launch the payload and the carrierspaceplane at the same time + it needs high cost maintenance after recovery and it flies badly)

So claiming spaceplanes (ssto or not) are really more economic is just pure absurdity, but we keep on seeing this here and in other posts.

We can also find a lot of challenges that can be fun, but are nonsense in the end for most of them.

The thread is about 'should' and showing where absurdity/scifi is and where real science is, is a good way to answer imo.

Edited September 21, 2015 by xebx

[Red Iron Crown]

claiming spaceplanes (ssto or not) are really more economic is just pure absurdity

IRL, yes. In KSP, with its tiny planet, super efficient airbreathing engines and zero refurbishing costs, no. Guess which this thread is about?

[Beachernaut]

Ok i am lacking precision : in real world :

SSTO spaceplanes don't exist

Spaceplanes were a big economical failure (you launch the payload and the carrierspaceplane at the same time + it needs high cost maintenance after recovery and it flies badly)

So claiming spaceplanes (ssto or not) are really more economic is just pure absurdity, but we keep on seeing this here and in other posts.

We can also find a lot of challenges that can be fun, but are nonsense in the end for most of them.

The thread is about 'should' and showing where absurdity/scifi is and where real science is, is a good way to answer imo.

Not sure if you've noticed, but there's quite a bit about KSP that doesn't fit "real world".

In KSP, in my experience spaceplanes are more economic, and the challenge is something I enjoy. If you don't have the same experience, that's ok. You don't have to use spaceplanes.