Point of spaceplanes?

[The Space Core]

I get the point of normal planes, traveling to different biomes on kerbin so you don't have to muck around with orbit and rotation. But what's the point of spaceplanes? Im probably just far too nooblike to know . But what uses to they serve? What's wrong with a normal old rocket?

~Thanks

The Space Core.

Edited October 23, 2015 by The Space Core
Question answered

[Claw]

Nothing wrong with a good old fashioned rocket. Some people just prefer to fly a plane to space sometimes. Also, it's often considered a bit of a different kind of challenge. Some designs can even haul quite a bit of stuff to orbit.

Humorously, there's a lot of stuff in KSP that doesn't serve a purpose, except to be there. Much of this game is wrapped up in the "I do these things because I can" sort of mentality.

Also, welcome to the forums!

Cheers,

~Claw

[The Space Core]

Ah, thanks for the prompt reply , I see now!

[Starhawk]

Well, uh, spaceplanes are fun!

At least for me.

Happy landings!

[Just Jim]

The reason for a space plane is cost, mostly. And the challenge of actually getting one into orbit... took me forever... lol.

Because there are no lower stages or boosters, a true space-plane SSTO should cost nothing to launch into orbit and return home but fuel. All parts can be retrieved.

[celem]

Yeah its the most cost effective way to get to orbit, staging gets costly fast. Even assuming you use a mod like stagerecovery to let you parachute in the SRBs and such you still wind up losing anything dropped from above about 40km as it burns up....and engines are expensive!

As Just Jim says, full recovery is possible, and even likely since your best chance at sticking a landing is on the runway which is 100%, you only pay for the cost of the fuel itself.

That said, spaceplanes have a terrible terrible payload fraction, if you are lifting any significant mass its an exercise in frustration, its probably cheaper to refuel your massive station with a spaceplane that pays only for the payload fuel and its own fuel, but it will take dozens of launches compared to what you can ship in a single dirty costly regular launch.

In practice I wont use it a spaceplane if I need to lift more than about 5t to LKO, it either means a lot of trips or a big plane that takes a lot of designing to get right.

Actually trying to use one to save you money isn't likely to happen, you need some pretty advanced tech to build a spaceplane, by that point in the game you should have monies, or the ability to gather some with some contract spam.

Seriously, getting an efficient spaceplane into orbit without certain parts is an exercise in futility.

They are fun to build and fly, but unless you have masochistic patience or a serious budget-crunch in the mid/late-game their actual gameplay value is more or less nil.

[GoSlash27]

The point of spaceplanes is to provide a cheap, safe, and reliable "delivery van" between KSC and a station in low Kerbin orbit and back.

They are unbeatable for the mundane logistical jobs that form the backbone of a space program, like rotating crews and delivering fuel to orbit. These are payloads that fit inside a fixed shape, transfer through a docking port, and would create major problems for your program if they couldn't be delivered with maximum economy, safety and reliability.

They're not as useful outside of those jobs, but a lot of people make them simply because they are more challenging (and hence fun) than the usual vertical lifters.

They take a lot more time, expense, expertise, and piloting skill to develop than vertical boosters. They are definitely not for everyone and honestly aren't worth the hassle in most situations. But where they *are* worth it... they are an incredibly powerful tool.

Best,

-Slashy

- - - Updated - - -

That said, spaceplanes have a terrible terrible payload fraction, if you are lifting any significant mass its an exercise in frustration, its probably cheaper to refuel your massive station with a spaceplane that pays only for the payload fuel and its own fuel, but it will take dozens of launches compared to what you can ship in a single dirty costly regular launch.

Celem,

Spaceplanes are actually *way* superior to vertical lifters in terms of payload fraction and can deliver huge payload masses for cheaper than anything else.... *if* they're done properly. It's the "done properly" part that's difficult.

Best,

-Slashy

Edited October 24, 2015 by GoSlash27

[Scarecrow88]

I used the last spaceplane I designed to carry 2 Mun landers to the Mun. Once they had been to the surface and returned to orbit, the spaceplane brought them both back to Kerbin. It was interesting to do in Sandbox mode, but in Career mode it would have saved me a whole lot on costs, as everything that was launched from KSC was brought back, with the exception of the fuel that was used.

[The Space Core]

So they are great for saving cost and ferrying crew. Ah, makes sense why I didn't see the point in them now, Im too much of a scrublet to go career. Sticking with science for now.

Edited October 24, 2015 by The Space Core

[Snark]

So they are great for saving cost and fearing crew.

An alternate viewpoint: It's true that spaceplanes are cheaper than rockets... but I've found that it's mostly moot. I've been playing KSP quite a while, and I never use spaceplanes (no particular rational reason, I just don't like 'em), and the finance works out just fine. There's plenty of cash floating around in contracts (particularly after you've climbed most of the tech tree, which you pretty much have to do to get good spaceplanes anyway). And a rocket works just about as well as a spaceplane for contracts, since the cost of the rocket is typically far lower than the contract reward.

In short: While it's true that spaceplanes are cheaper, it's also (in my experience) irrelevant.

The real reason to fly spaceplanes is because you like them. There are spaceplane folks, and there are rocket folks. Nothing wrong with either one, they're both perfectly valid and you can have a perfectly good career game with either one. It all just comes down to personal preference-- you pays your money and you takes your choice.

Im too much of a scrublet to go career. Sticking with science for now.

And don't be down on yourself-- if you can get payloads to orbit, you can do career!

[Just Jim]

I used the last spaceplane I designed to carry 2 Mun landers to the Mun. Once they had been to the surface and returned to orbit, the spaceplane brought them both back to Kerbin. It was interesting to do in Sandbox mode, but in Career mode it would have saved me a whole lot on costs, as everything that was launched from KSC was brought back, with the exception of the fuel that was used.

Well, if we're showin' off... lol...

Seriously, this is my first true Spaceplane. She can't haul cargo, but she can take a total of 6 crew into orbit and/or back. And while it's sort of hard to see, she also has an Mk2 inline docking port, so I can dock with an orbital shuttle to transfer personnel and refuel if needed. I love flying this thing!!!

[Red Iron Crown]

There are spaceplane folks, and there are rocket folks.

Worth pointing out that some folks are both, it's not an either/or proposition. One can just as easily run a space program with a mix of planes and conventional rockets.

[Alshain]

I used to be both but 1.0 made planes not so fun anymore for me. Now it feels more like pounding your head against an immovable brick wall. But before 1.0 I used to lift massive payloads into Space with the Ferram Aerospace Research mod and build entire spacestations. I was one of the dozen or so go to guys for plane building advice on the forums. Sadly I think those days are over as long as the jet engines are so weak. These days if I want to fly planes, I go back to 0.90.

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Edited October 24, 2015 by Alshain

[Dispatcher]

Space planes are a challenge for me. That's why I like them. Making a variety of craft in the game is fun: space planes, rockets, rovers, boats, aircraft, etc. Have fun!

[cantab]

I recently spent a couple of days making a basic, single-seater spaceplane to get into LKO. Got there in the end, albeit only barely.

I then knocked up a rocket SSTO with space for two Kerbals and the ability to land back on Kerbin in a fraction of the time. Though it's true that the rocket uses about four times as much fuel per Kerbal.

[The Space Core]

Those all look incredible! Too bad the best I can do is a manned minimus probe .

[MartGonzo]

Worth pointing out that some folks are both, it's not an either/or proposition. One can just as easily run a space program with a mix of planes and conventional rockets.

I was a purely rocket man to start, but recently I've fallen in love with space planes, not for reasons of practicality (although I do use them for Kerbin rescue missions) but just because of the design freedom they offer.

Those all look incredible! Too bad the best I can do is a manned minimus probe .

oh don't worry about that, we've all started out that way.

the more you play, the more ambitious your projects will get.

Edited October 24, 2015 by MartGonzo

[FlyingPete]

I've built a few spaceplanes (not all SSTO) and can see the usefulness of them in terms of 100% recovery less fuel. For practical purposes, they're not much good to me other than as a crew bus as the payload fraction is always so low. It was always fun on the old aero to go suborbital while still in the atmosphere, needing only a small rocket engine or RCS to make orbit. I daresay it was possible to orbit a pure-jet aircraft by the 'get out and push' method.

Whenever I've used them, they never go further than a station in LKO- some orbital craft can take things from there.

[KerikBalm]

To follow up on the comments about spaceplanes having terrible payload fractions:

http://forum.kerbalspaceprogram.com/threads/116729-Stock-Payload-Fraction-Challenge-1-0-4-Edition

The top spaceplane in that challegne has a 53.37% payload fraction.

The closest non-spaceplane gets a 44.56% payload fraction... and its really expensive because its an airbreathing multistage rocket... discarding airbreathing engines and intakes leads to high launch costs.

The closest non-airbreathing rocket payload fraction is 28.61

Then there's people that say they can get good payload fractions, but the payload should be something small, like fuel in a tank, or that fits in a cargobay...

nonsense...

I launched this thing with just two SSTOs:

Obviously its not a spaceplane, which illustrates the point that you don't have to be either a "spaceplane guy" or a "rocket guy"

Its a fully re-usable/recoverable moho mission by the way...

I recover the pod at the end, and the spaceplanes that launch it at the beginning, everything else gets refueled and reused.

Although at the moment, I'm not sure how the return stage wil fare during reentry... the pod has ~50 m/s and a heat shield so it can put itself on a more aggressive direct aerocapture/return... We'll see if the return stage will have enough dV/heat resistance to be re-used...

Would be a tragedy if it broke up in the atmosphere and the nukes came down on Kerbin...

I just had to launch the ejection stage consisting of the KR-2L and 2 LV-Ns into orbit separately, and dock it with the rest of the craft (the SSTO had reserve fuel to refuel the ejection stage after docking)

The main craft:

(yea, this one was pushing the limits of acceptable payload dimensions... I had to fly off the end of the runway to keep the end of the payload from striking the runway when lifting off)

The ejection stage section was easy to lift and fit in comparison:

And then "full recovery" in the end:

In this case, the cost of the payload fairing is a significant fraction (around 33%) of the total launch cost.

Imagine if your rockets cost the same as just putting the payload in a fairing 3 times?

For some payloads, I don't even need to use a fairing... or a small fairing is fine:

[ForScience6686]

I enjoy the challenge they present. It's also a nice feeling to glide out back to the runway from orbit. My duna mission is primarily all rockets, except for my last craft which is a space plane that will bring everyone home.

And just because it's a space plane does not mean it has to be an ssto. I used boosters on mine for accelerating above mach 1 and again to boost the low twr of the nukes. There's endless opportunities by having both aspects to the game.

[GoSlash27]

Worth pointing out that some folks are both, it's not an either/or proposition. One can just as easily run a space program with a mix of planes and conventional rockets.

^ Truthiness.

I use a mix of both. Spaceplanes for the stuff that spaceplanes excel at and vertical lifters for the rest.

*edit* as long as we're showing our spaceplanes...

Big heapin' helpings of fuel and o2 to orbit for cheap.

Best,

-Slashy

Edited October 24, 2015 by GoSlash27

[The Space Core]

Oh my, that is absolutely incredible, I simply can't believe it! It looks almost impossible! But thats just my nooblike mind talking:/. Alright I have to get a space station core into orbit, Im going to try to use a spaceplane to do it.

[Just Jim]

Worth pointing out that some folks are both, it's not an either/or proposition. One can just as easily run a space program with a mix of planes and conventional rockets.

I also totally agree!!! I use both heavy rockets and spaceplanes. Depends on the mission contract.

[SpaceplaneAddict]

My name says what I am. I love the challenge, and TBH, I've spent so much time with SSTO's and spaceplane SSTO's, that I've become a complete rocketry idiot.

[KerikBalm]

Then you just need to go design a cargo SSTO... I've only recently seen people start to post cargo SSTOs where there are provisions for a wide variety of payload sizes, enclosed by a fairing, and held rougly at the CoM so you can "drag and drog" your payload into the SSTO.

Start lifting rockets with SSTOs... 100% re-usable/recoverable to Moho is a good goal, IMO.

If you can do that... you can supply an orbital fuel depot pretty much anywhere without ISRU.

No place takes more dV to get to, capture into orbit, and then depart from, than Moho.

You'll need to use staging rockets for that... and designing a staging rocket to be reusable is a nice challenge too

Stage #1: spaceplane to LKO

Stage #2: Eject to moho intercept (then retroburn and aerobreak to LKO)

Stage #3: Capture into Moho orbit (optional: detach a fuel tank/depot/station in moho orbit), depart moho orbit

Edited October 24, 2015 by KerikBalm