Are spaceplanes worth it?

[Dizzle]

I mean, besides for the fun of it, aren't they more trouble than they're worth? They're hard to even get into orbit, from there will likely require a refuel, and to top it all off, still have to land horizontally back on Kerbin with extreme precision.

Edit: Absolutely not saying they're not awesome, though.

[tavert]

I agree with you, planes are fiddly, and for me they're less fun than rockets. You can try playing with the FAR mod to make the aerodynamics less strange, or just stay ballistic if planes aren't your cup of tea.

Don't discount the efficiency of the jet engine though, it can be quite useful in getting rockets out of the atmosphere.

[Tada]

It depends...

I like to use them for my mission on Laythe, since I can land them with precission where I want and I use them as a mean of evacuation from space station in LKO...

[Lazro]

Spaceplanes are great fun-If you have one fuel tank directly over the center of mass, that is...

[SalmonellaDingDong]

I used to hate planes. Hated building them, hated flying them. Now it's almost all I do. I build ten planes for one rocket.

If you design them right they can be very useful. Check out the FAR Kaiju. That made it to orbit with 5900dV remaining, and I have taken one to Duna and one to Laythe with no refueling.

I think planes are more fun than rockets because of the wider variety of designs that can be built. You often see similar looking rockets but I've seen a lot of crazy plane designs I would have never thought of. I'm able to incorporate those designs I see into my own builds, and as I get more experience building planes they get better and better.

The new B9 release has really made me enjoy planes built using those parts since it's now a complete set. Mixing mod and stock parts can make unique designs that are still functional.

For anyone that doesn't like planes I suggest installing FAR, which makes the aerodynamics a lot more realistic and that makes planes more fun. with FAR you can actually go fast in the lower atmosphere like a real plane could. It also makes it so realistic looking designs actually fly, something that is hit or miss with the stock placeholder aerodynamics.

Here is a link to the FAR thread for anyone interested: http://forum.kerbalspaceprogram.com/showthread.php/20451-0-20-Ferram-Aerospace-Research-v0-9-4-Aerodynamics-Fixes-For-Planes-Rockets

Here is the B9 thread: http://forum.kerbalspaceprogram.com/showthread.php/25241-0-20-2-B9-Aerospace-Pack-R3-New-pods-IVAs-engines-fuselages-structures

PS: FAR will make rockets easier too since it helps to use nosecones and fairings to reduce drag, like real life.

[Sᴄɪɴᴛɪʟʟᴀᴛᴏʀ]

They have their uses but unfortunately these can be quite limited with the current aerodynamics model. Ferram Aerospace does a lot for the spaceplane in this regard but still leaves a bit to be desired.

[3_bit]

They're typically SSTO, so yes if you want to be all legit with a reusable space program.... I personally play around with them, mostly failing.

[Spatzimaus]

Even without FAR, spaceplanes have a few significant advantages over normal rockets, at least when dealing with planets possessing an atmosphere.

The first big advantage is precision. A rocket trying to land on a planet/moon possessing an atmosphere will be lucky to end up in the same zip code as the destination point; in the current stock KSP there's not much need to land on a specific site, barring anomalies, but once the new resource system comes in (or if you use the Kethane mod now), being able to land on the right spot becomes very important. This is a major issue on Laythe, where good landing sites are few and far between; a rocket will have a difficult time ensuring a good landing site, but spaceplanes can easily find a safe place to land. On your return to Kerbin, a spaceplane can also land right back on the runway at KSC with ease.

The second is a matter of forces. A winged design can easily and safely land on a thin-atmosphere body like Duna, whereas a "brick" rocket using parachutes runs into a serious problem: the atmosphere's so thin that if you come in at a shallow angle (i.e., an aerobrake), parachutes simply won't have enough time to cancel out your lateral motion before you impact the ground, and the retarding force of parachutes on a decent-sized craft won't be enough to ensure a good gear-down orientation. Also, the moment of deployment for parachutes can rip your design apart if it's still got too much speed, even with drogues, whereas a winged design can take its time bleeding off the reentry speed without having to worry about tearing itself to pieces. And on a thick-atmosphere world like Eve, a spaceplane can literally glide the whole way down without using any fuel at all. (Of cource, you'll need to use mods if you want to take off again...)

Finally, spaceplanes have a significant fuel efficiency advantage if you only want to get to low kerbin orbit; even though you're spending far longer in the lower atmosphere, with all its drag, the ridiculously high ISP of jet engines means that once you're in the upper atmosphere you'll use very little fuel building up the horizontal speed you need to orbit. The limiting factor is generally intake air, but if you put enough intakes on your design (relative to the number of engines) you can actually GAIN air even at 20km, giving you all the time you need to add more speed. Once we get a career mode, with some sort of economics, this (and the lack of disposable stages) might give spaceplanes a major advantage over rocket stacks. But for this to work you need to have a well-designed spaceplane; the transition from aerodynamic flight to a sub-orbital trajectory requires a rocket engine with enough thrust to do the job, as well as rockets with enough efficiency to cheaply circularize once you're in orbit. If your plane has too little rocket power, it'll just end up wasting a ton of fuel getting out of the gravity well.

[M5000]

Please be advised: No.

[tavert]

Re: Spatzimaus,

You can do pinpoint ballistic landings, it just requires some predictive math. With practice people regularly land rockets back at KSC even without MechJeb's calculator doing the math real-time.

Wings add mass, powered landing after the atmosphere has slowed you down to terminal velocity doesn't take all that much fuel.

Nothing stopping you from using jet engines on rockets, getting the same fuel efficiency benefit. A vertical trajectory through the lower atmosphere is typically more efficient than horizontal launch, unless your TWR is very low. And jet engines are fairly heavy to carry around in space with you, better to stage them away once you get into Kerbin orbit, unless you're going to Laythe or coming right back from LKO. For reusability you could put parachutes and probes on the jet booster stages, though the physics draw distance makes that problematic at the moment.

[Temstar]

If the goal is to lift a whole range of big payloads to space then you're better off with rockets. SSTO spaceplanes typically don't carry much payload if any and even the larger cargo SSTOs designed to carry payload have some pretty strict requirements on both payload mass and dimensions. If you attach a load only slightly off from the original design payload in terms of mass or dimensions you will throw the COM of the whole craft off and make the combination unairworthy.

This is opposed to rockets which simply have a maximum designed lift capacity to orbit. As long as you stay under this lift capacity of your carrier rocket and the COM of your payload is reasonably centred the rocket will be able to place your payload into orbit regardless of how high or low the COM of the payload actually is. Once you have a range of rockets for different payload capacity you can just stay with them for the rest of your space program. Every time a new payload needs to go up just weight it and attach the appropriate sized rocket underneath and you're done. You can't do that with spaceplanes.

[Van Disaster]

For anything up to 25-30t to KO I like to throw it in the back of a plane, it saves customising a launcher. For moving Kerbals around, I also just send them in a plane - I have at least one design that'll take four + pilot to Mun and back using retrothrust at Kerbin rather than aerobraking - understandably, aerobraking a streamlined aircraft takes quite a while, but re-entering too fast is rather more dangerous than in a rather more robust rocket - which would be plenty to send them practically anywhere in the system if I had manned missions that far away ( not necessarily back as well, but that can be tricky with rockets too ). Currently working on versions which use Kethane rather than jet fuel.

SSTO isn't really necessary, you can use droptanks - some of the conformal designs are quite useful for that ( albeit might want their capacities reduced a little ). That way you can also have fuel somewhat off the centre of mass & dump the tanks before you've lost any torque from your aerodynamics to counter it.

TLDR; yes, if you're lazy.

[SalmonellaDingDong]

Wouldn't rockets be for the lazy since they're easier and require less design?

[Van Disaster]

Well as I just mentioned, they don't take any design at all now just have to attach the payload at CoM and off we go. There was quite some iterative work to get a reliable spacecraft though, yes. It takes me longer to construct a rocket even with a bunch of saved subsystems, although I guess I could just pull out the smallest likely one & ignore the waste.

[SalmonellaDingDong]

I build a new lifter every single time. Using the same one would get boring to me.

[bsalis]

Meh.

Each to their own.

[rodion_herrera]

The idea for a "space plane" has military origins. I mean, in terms of national defense, it's way easier for a pilot to control the airspace (and the "space" above that airspace) from a winged craft, rather than a rocket. Since KSP doesn't have a military component, spaceplanes, apart from the "WOW" aspect of actually being able to make one, and SSTO in one, is more of eyecandy than anything else. But I still love them

[TwoHedWlf]

I prefer to use a rocket for the top stage and a spaceplane for the return stage. Much greater cargo capacity and simplicity to get to orbit and then you have the extra control on re-entry.

[cpt_nosh]

In my opinion, SSTO planes are like a more difficult class... like a higher difficulty setting for the game. Build one with the given symmetry and you might manage to get to Orbit after a while. Start adding tanks on top so the point of mass, -thrust go ape**** and you might have gotten to a high end playstyle. Try to make it good looking at the same time, it gets even harder.

So, I dare to say, they will be more important, efficient and most of all easier to use when there are more fuselage and aerodynamic parts. For example a fuselagepart with oxidizer within, or one with RCS.

So far

cpt_nosh

[SalmonellaDingDong]

All those parts already exist.

http://forum.kerbalspaceprogram.com/showthread.php/25241-0-20-2-B9-Aerospace-Pack-R3-New-pods-IVAs-engines-fuselages-structures

[cpt_nosh]

I haven't used any plugins until now. But in this case I might try something like that out. Thanks for the link.

[Brotoro]

I think it's much easier to launch a wide variety of payloads on rockets. I suppose spaceplanes could be useful for simple crew transfers to/from orbit, but I have SSTO rockets that I can do that with faster and easier than I can with a spaceplane, which I found to be very finicky to fly well.

But one should never discount the fun factor for those that like 'em.

[Brotoro]

Also, I don't mind using MechJeb to target precision landings for my rockets.