More plane fun! (and questions)

[goldenpsp]

So my first post in here about planes was more about flying. I had found an example of a rescue SSTO for all those kerbal in orbit missions, copied the plane from the screenshots and failed horribly. You were all extremely helpful in that regard.

I then took the stock Aeris-4A, and modified it for my rescue SSTO. It has flown to great success and I feel far more confident at flying. I can get in orbit, snag the kerbal and land on the runway every time now.

I have also added some mods, notably:

NEAR (not ready for FAR quite yet but wanted something better than stock)

Splaceplane+

MKS/OKS

So in building my OKS station, and playing career, I am trying to save costs where I can. I have also been enamoured with the parts from spaceplane+. So I have wanted to build 2 new SSTO's. A Kerbal shuttle (using the SP+ crew module) and a light cargo shuttle, using the cargo bay.

My first question is in building. I have found the SPH to be utterly maddening so far. Getting wings to snap on just so and line up takes far more effort than it seems like it should. It seems like i can spend upwards of 30-60 seconds sometimes getting a wing section to "go green" only to then try and adjust forward or back a little and screw it up. So I didn't know if there are any tips/tricks/helpful mods I am missing or it is just a clunky interface.

Similarly, with these larger planes the issue is compounded. If while building up the wing I realize it should really be shifted a little, there is no way to grab all the wing sections as a unit. So it seems I have to end up tearing it all down and starting over.

As for the actual ships, my main question is the viability of a horizontal takeoff SSTO cargo hauler. Using tweakscale I can shrink 2 of the MKS cargo cans so that 2 fit perfectly in the spaceplane+ cargo bay. completely full they come in at just around 10 tons. Is it possible to build a SSTO to handle that kind of weight without being some huge monstrocity? Or should I consider a more shuttle style rocket assist takeoff/plane landing type of setup?

Also, is there any way to get an idea of wing loading/lift characteristics, or is designing the wing a pure trial and error experience? I have also had a hard time with these larger planes figuring out how much wing I actually need.

Thanks

Edited August 12, 2014 by goldenpsp

[Pecan]

...As for the actual ships, my main question is the viability of a horizontal takeoff SSTO cargo hauler. Using tweakscale I can shrink 2 of the MKS cargo cans so that 2 fit perfectly in the spaceplane+ cargo bay. completely full they come in at just around 10 tons. Is it possible to build a SSTO to handle that kind of weight without being some huge monstrocity? Or should I consider a more shuttle style rocket assist takeoff/plane landing type of setup?

Yes, you can build good-looking stock craft to lift 10t. Well, maybe you can't and I certainly can't but Hodo, WanderFound and others will be along soon. Why go to all this trouble for a horizontal landing though? You can build a powered-landing SSTO rocket to lift 10t with 20 parts or fewer and it's a lot quicker and easier to fly.

[Wanderfound]

My first question is in building. I have found the SPH to be utterly maddening so far. Getting wings to snap on just so and line up takes far more effort than it seems like it should. It seems like i can spend upwards of 30-60 seconds sometimes getting a wing section to "go green" only to then try and adjust forward or back a little and screw it up. So I didn't know if there are any tips/tricks/helpful mods I am missing or it is just a clunky interface.

Similarly, with these larger planes the issue is compounded. If while building up the wing I realize it should really be shifted a little, there is no way to grab all the wing sections as a unit. So it seems I have to end up tearing it all down and starting over.

As for the actual ships, my main question is the viability of a horizontal takeoff SSTO cargo hauler. Using tweakscale I can shrink 2 of the MKS cargo cans so that 2 fit perfectly in the spaceplane+ cargo bay. completely full they come in at just around 10 tons. Is it possible to build a SSTO to handle that kind of weight without being some huge monstrocity? Or should I consider a more shuttle style rocket assist takeoff/plane landing type of setup?

Also, is there any way to get an idea of wing loading/lift characteristics, or is designing the wing a pure trial and error experience? I have also had a hard time with these larger planes figuring out how much wing I actually need.

When building multi-part wings, give some thought to what you attach each bit to. Ideally, you want the whole wing connecting through a single root node so you can move it as a single piece. As for placing them, I find it helps to try and get the wing position sorted before you clutter up the plane with too many other parts that get in the way. Often, when a wing won't "go green", it's just because there's an RCS block or similar small part in the way. If all else fails, you can always use the debug menu (Alt-F12) to temporarily enable part clipping.

FAR provides assorted technical analysis tools (NEAR doesn't), but you don't need to use them. I design purely by eye and flight testing.

Heavy lift stock SSTO's are certainly possible; big ones (50+ ton payload) are tricky to build, but small to medium cargo lifters aren't too hard. If you've got enough wing and thrust to get off the runway, then you've probably got enough to go to space. See http://forum.kerbalspaceprogram.com/threads/88628-Kerbodyne-D7-Heavy-X5-a-heavy-lift-SSTO-spaceplane for an example of a heavy cargo stock SSTO spaceplane.

On a more modest scale, something like this isn't hard to build with Spaceplane Plus:

Getting spaceplanes to work for you is as much about piloting as it is building. See http://forum.kerbalspaceprogram.com/threads/89643-SSTO-question?p=1334110&viewfull=1#post1334110 for some tips.

Edited August 12, 2014 by Wanderfound

[goldenpsp]

Yes, you can build good-looking stock craft to lift 10t. Well, maybe you can't and I certainly can't but Hodo, WanderFound and others will be along soon. Why go to all this trouble for a horizontal landing though? You can build a powered-landing SSTO rocket to lift 10t with 20 parts or fewer and it's a lot quicker and easier to fly.

Because I can (or more appropriately should be able to). I can land more reliably on the runway for 100% recovery with a plane. And I just find them way more fun to fly at the moment.

When building multi-part wings, give some thought to what you attach each bit to. Ideally, you want the whole wing connecting through a single root node so you can move it as a single piece. As for placing them, I find it helps to try and get the wing position sorted before you clutter up the plane with too many other parts that get in the way. Often, when a wing won't "go green", it's just because there's an RCS block or similar small part in the way. If all else fails, you can always use the debug menu (Alt-F12) to temporarily enable part clipping.

Yea I have been building the fuselage and then wings before anything else. I figure if I can't get the wings sorted why continue.

Heavy lift stock SSTO's are certainly possible; big ones (50+ ton payload) are tricky to build, but small to medium cargo lifters aren't too hard. If you've got enough wing and thrust to get off the runway, then you've probably got enough to go to space. See http://forum.kerbalspaceprogram.com/threads/88628-Kerbodyne-D7-Heavy-X5-a-heavy-lift-SSTO-spaceplane for an example of a heavy cargo stock SSTO spaceplane.

Yea I have that one bookmarked.

On a more modest scale, something like this isn't hard to build with Spaceplane Plus:

http://i1378.photobucket.com/albums/ah120/craigmotbey/Kerbal/screenshot327_zpscafc1a33.png

Nice looking! Is this something that would have enough lift for a 10T payload? If so I am totally overengineering how much wing I need. It is hard to know starting out.

Getting spaceplanes to work for you is as much about piloting as it is building. See http://forum.kerbalspaceprogram.com/threads/89643-SSTO-question?p=1334110&viewfull=1#post1334110 for some tips.

Yes you helped me greatly in my other thread. I'm certainly not going to say I'm an expert but the planes I have that do fly I can get into orbit and land reliably now.

[Wanderfound]

Nice looking! Is this something that would have enough lift for a 10T payload? If so I am totally overengineering how much wing I need. It is hard to know starting out.

I'd expect so, but I haven't used the Spaceplane Plus parts much yet; I like the challenge of doing it stock. OTOH, my dodgy old laptop likes the drastically reduced part count that SP+ allows. I'm planning on designing some SP+ lifters today; I'll post them to the Spacecraft Exchange if I come up with anything good.

For designing lifters, the NRAP mod is very useful. It's a single-part pack that gives you a test weight of widely tweakable size and mass. And remember that wings add drag as well as lift; especially if you're flying with FAR/NEAR, too much wing is counterproductive.

[goldenpsp]

I'd expect so, but I haven't used the Spaceplane Plus parts much yet; I like the challenge of doing it stock. OTOH, my dodgy old laptop likes the drastically reduced part count that SP+ allows. I'm planning on designing some SP+ lifters today; I'll post them to the Spacecraft Exchange if I come up with anything good.

For designing lifters, the NRAP mod is very useful. It's a single-part pack that gives you a test weight of widely tweakable size and mass. And remember that wings add drag as well as lift; especially if you're flying with FAR/NEAR, too much wing is counterproductive.

Good advice.

I'm going to go see if I can copy that setup from your picture now

Update- I'm not even sure I got everything right from the picture but it flies like a freakin dream. You def have the plan development skillz

Edited August 12, 2014 by goldenpsp

[Wanderfound]

Okay: see http://forum.kerbalspaceprogram.com/threads/90344-Kerbodyne-Velociraptor-light-cargo-express-SSTO-for-Spaceplane-Plus-and-FAR?p=1345986#post1345986 for a Spaceplane Plus demonstrator. If you want a bigger cargo bay, it can probably be stretched without much trouble; just be sure to adjust the position of the aero surfaces to maintain the CoL/CoM alignment.

[Wanderfound]

Good advice.

I'm going to go see if I can copy that setup from your picture now

Update- I'm not even sure I got everything right from the picture but it flies like a freakin dream. You def have the plan development skillz

Aww, shucks.

[Wanderfound]

Good advice.

I'm going to go see if I can copy that setup from your picture now

Update- I'm not even sure I got everything right from the picture but it flies like a freakin dream. You def have the plan development skillz

BTW, ways to improve it further:

* Use the tweakables on your control surfaces. Crank the control authority to max (back it off if they start tearing off, though), set the rudders to yaw only and the rest to everything but yaw. Set some control surfaces both front and rear as maxed-out spoilers; they'll flip up to act as downforce-generating airbrakes when you hit the brakes on landing. Also useful for getting canards clear of the ladder you should be putting under the door.

* The original had RAPIERs on the wings and a turbojet in the middle. This lets you keep the turbojet (only) running at extreme altitude without worrying about asymmetric flameouts or premature mode-switching, and the pure air-breather can take advantage of the ram-air effect when the RAPIERs switch to rocket mode. Plus, turbojets sound a lot nicer than RAPIERs.

* Run struts from the underside of the wingtips to the fuselage. This doesn't matter so much in NEAR, but if you switch to FAR you'll have to deal with the possibility of your wings tearing off if you let your angle of attack become excessive at low altitude.

* Don't forget to unlock the steering on your front gear.

* The lights on your landing gear are good enough for a ventral docking port, but you may want some upwards-pointing lights if you're using the Spaceplane Plus inline dorsal port.

* Spaceplane Plus includes a supply of RCS fuel in both the cockpit and the inline docking port. Stick a pair of linear RCS thrusters (spaced evenly around CoM) on each facing for use in docking. They can also sometimes save you if you lose control at high altitude. You can stick a linear thruster in the centre of a RAPIER without it getting fried by the exhaust. Make sure you've got some pointing forwards as well; rotate them if necessary.

* Make at least some of your tanks pure liquid fuel (no oxidiser). Because you're using atmospheric oxygen on the way up, you'll always have unused oxidiser if you don't do this.

* Consider putting nacelles behind the intakes. Extra intake plus liquid fuel = bonus.

* Use fuel lines to control the order in which your tanks drain, and to make sure that you can keep running all engines until the tanks run dry. I usually run a pair of lines from the lateral tanks to the core, then another pair from the core to the lateral engines.

* Vernors can do awesome things for planes. Vectored thrust massively expands the performance envelope, and a few Vernors on the underside will let you do VTOL landings on the Mun or Minmus (hit "control from here" on the docking port to orient the navball for this). Keep them turned off until you need them, though.

* Use lots of action groups. One to toggle the turbojet, one to toggle the RAPIERs, one to switch modes on the RAPIERs, one to toggle each type of intakes, one to extend your solar panels, one to release whatever's in the cargo bay, one to toggle the Vernors, one to run a crew report and trigger all the scientific instruments.

* Including the Spaceplane Plus drone core segment will let you rescue Kerbals with a single-seater. Alternatively, stick a Stayputnik in the cargo bay.

* If you have high-speed handling issues, just behind each intake is a good place for an ASAS unit.

* Try flying from IVA sometime. It's a hoot.

[goldenpsp]

* The original had RAPIERs on the wings and a turbojet in the middle. This lets you keep the turbojet (only) running at extreme altitude without worrying about asymmetric flameouts or premature mode-switching, and the pure air-breather can take advantage of the ram-air effect when the RAPIERs switch to rocket mode. Plus, turbojets sound a lot nicer than RAPIERs.

HAHA. I couldn't really tell from the picture that there was even a turbojet on the back so mine is missing and it still performs well...

Hardest part at this point is getting the darn cargo loaded sometimes.

Edited August 12, 2014 by goldenpsp

[Wanderfound]

HAHA. I couldn't really tell from the picture that there was even a turbojet on the back so mine is missing and it still performs well...

Hardest part at this point is getting the darn cargo loaded sometimes.

The Editor Extensions mod may help you there.

It's also not a bad idea to leave a decoupler or a pair of mated docking ports attached to one end of the bay, build your cargo as a subassembly and then attach it to that. Means you only have to fight with the cargo bay's attachment dodgyness once.

[Wanderfound]

You should give the new one a try. It's ridiculously quick.

With FAR and aerodynamic failures turned on, you can't leave it at full throttle below 10,000m for more than a minute or so before the plane basically explodes from the air pressure.

Edited August 12, 2014 by Wanderfound

[goldenpsp]

You should give the new one a try. It's ridiculously quick.

With FAR and aerodynamic failures turned on, you can't leave at full throttle below 10,000m for more than a minute or so before the plane basically explodes from the air pressure.

I have tried the new one, albeit with NEAR (haven't graduated to FAR yet). It's like a hot knife through butter.

The Editor Extensions mod may help you there.

It's also not a bad idea to leave a decoupler or a pair of mated docking ports attached to one end of the bay, build your cargo as a subassembly and then attach it to that. Means you only have to fight with the cargo bay's attachment dodgyness once.

I will have to try the extensions. And yes that is kind of what I did. I had plans to carry docking segments to my orbital station. Thought it would be fun to mount on an infernal robotics hinge so it can swing out and I can dock it in place in one shot. Put the hinge and docking port on the plane. Built the cargo, docking port first and saved as a sub. When i try to get them to mate it's like trying to push 2 magnets together with the same poles.

Hmm maybe I need to do like you mention and put both docking ports together on the plane and build the sub without the docking port...

[Master Tao]

Thought it would be fun to mount on an infernal robotics hinge so it can swing out and I can dock it in place in one shot. Put the hinge and docking port on the plane.

That would trigger a known bug with IR. At best, IR parts attached to docking ports are messed up. Otherwise, you'll probably see spontaneous unplanned disassembly.

[goldenpsp]

That would trigger a known bug with IR. At best, IR parts attached to docking ports are messed up. Otherwise, you'll probably see spontaneous unplanned disassembly.

Ah, so connect with a decoupler or something instead?

[Master Tao]

As long as you don't move the docking ports with IR, you should be fine.