An Affordable Space Program: making the reusable spacecraft pay off.

[SirJoab]

Wow gchristopher, I like your solution, it's so different than anything else I've seen! Good luck!

[Kasuha]

I can see some obstacles in stitching another cycle to the right of this one. Because you are only allowed to deploy next "package" and fuel, so you have to

- refuel the plane and rocket (can be done while they're still docked)

- decouple the rocket from the plane

- attach new package to the rocket

- get the rocket vertical again for next launch

And you also have to keep the tow vehicle fueled in the course

[gchristopher]

Thanks for the feedback. It landed successfully!

Turns out my problem was this:

Pilot error.

Jeb insisted that any landing slower than 120 m/s is "for wimps." I think he's against the whole reusable ship concept, as the launches of Oops Sats 1-6 were highly profitable for his junkyard business.

Anyway, Jeb was MIA after Oops Sat 6, so I put Bob in the cockpit, added a little lift, and he landed it at a sedate 54 m/s. It probably doesn't need half the structural reinforcement that were added trying to get it to land at higher speeds.

Not a hint of damage, so I'm going to go back and remove a lot of struts to lower the part count.

I can see some obstacles in stitching another cycle to the right of this one. Because you are only allowed to deploy next "package" and fuel, so you have to

- refuel the plane and rocket (can be done while they're still docked)

- decouple the rocket from the plane

- attach new package to the rocket

- get the rocket vertical again for next launch

And you also have to keep the tow vehicle fueled in the course

Yep, the rocket comes close to righting itself when decoupled, and could probably be stood up just with landing gear. Or I've fiddled with rounded gantries to roll it upright, etc, etc. Went through all that making a modular rover-based stock launch gantry for an earlier project. It was kinda dumb.

But really, I'm sick of wrestling with the wobbly physics engine and stock Kerbals not having invented the hinge yet. I'll use Infernal Machines mod for the ground support, which will make docking/aligning the vehicles reasonably easy.

Anyway, yay for learning to land!

The space station engineers refused to hand over any modules until we'd demonstrated that we could actually land the vehicles. So during the learning process, we just kept launching one Oops Sat refueling station after another. (The first landing was after deploying Oops Sat 7.) So, as a side bonus, there's now 150+ tons of fuel in low Kerbin orbit for use in this or other projects.

Edited March 20, 2014 by gchristopher

[SirJoab]

I can see some obstacles in stitching another cycle to the right of this one...

[Kasuha]

http://i234.photobucket.com/albums/ee229/Sir_Joab/1377949_10200750931791925_1486371308_n.jpg

I don't see anything about it being "impossible" in my statement. I didn't even mean it was impossible so I wonder where are your "words of wisdom" coming from. I just meant the diagram describes the easy part of the process.

[LordFjord]

@gchristopher:

cool stuff, I'm curious how you will handle the "rearm/refuel" phase. Even with Infernal Robitics support thats no easy task.

@SirJoab: have you looked at my entry update (some time ago)? I know I've bent some rules and will - if at all - be the last in the list. It would make me proud anyway, even as a honorable mention.

[gchristopher]

I just meant the diagram describes the easy part of the process.

Haha, yeah, wow. Given how many times I failed at the "easy" part, I'd hate to see what you consider "hard".

I'm going back to Minmus until I have enough Science to unlock all the solar panels and batteries and whatnot that go on a station...

@gchristopher:

cool stuff, I'm curious how you will handle the "rearm/refuel" phase. Even with Infernal Robitics support thats no easy task.

In fairness, I'm curious how I'll do it too!

Edited March 20, 2014 by gchristopher

[LordFjord]

The hard part?

Somehow grab your launcher, turn it and point the correct end towards the sky. This isn't easy, especially with heavy parts.

How do you want to attach the next module on it? How to refuel it? Via big badass rover/crane?

Your launcher is standing on 4 legs - and each is important so it doesn't fall to the side. Pray that they wont break on any critical phase (like attaching the next module, refueling), or add some redundancy

[SirJoab]

...@SirJoab: have you looked at my entry update (some time ago)? I know I've bent some rules and will - if at all - be the last in the list. It would make me proud anyway, even as a honorable mention.

Aww man... sorry about that LordFjord! I'm glad you spoke up.

Here's your score:

+4 for 4 Modules

+18 for 18.6 Tons

-3 for 3 refuels

+4 for 4 Kerbals

+2 for style.

Total: 31 points.

Not a huge score, but this is a really beautiful setup. Nice Job!

[Keldaria]

Lots of nice idea's and designs in this thread. I'm currently planning out an entry, but I'm just taking it 1 step at a time. Currently focusing on building a stable SSTO launcher with a 10+ ton lift capacity. My current design features a top loaded cargo meaning I'd likely require a crane system of some sort, but I might be able to flip the design of the cargo mount to take a feed from the bottom..

[Rakaydos]

If someone else has a functonal crane design that doesnt require flying dockings, that can support rockomax docking ports, I would like a craft file. Reassembily is the part I'm failing at.

I'm also considering an "honorable mention" that includes attaching new SRBs as part of the "refueling" process

[gchristopher]

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You guys were right. That was challenging and tedious. But, it's completed a full refueling and relaunch sequence! Werner kicked us off the launch pad, so we're launching from the R&D campus.

The second picture is a spectator's view of the full ground operations fleet. Top left, the rocket/payload gantry is bringing in the science/escape pod cluster module. The Up Chuck rocket is connected to a support gantry (which was more trouble than it's worth). A fuel truck connects to the support gantry.

23.066t payload this time. I think it's pushing very close to the max liftoff weight, though. The full space station will take a while. The ground operations could still use some tweaking.

If someone else has a functonal crane design that doesnt require flying dockings, that can support rockomax docking ports, I would like a craft file.

Would you like a copy of the Infernal Machines-based one I'm using? It's pretty tedious to use, but better than nothing.

[Kasuha]

That was challenging and tedious. But, it's completed a full refueling and relaunch sequence!

Congratulations, there's no stopping you now

[Keldaria]

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Sorry I'm taking so long, still planning to do this but I just don't get a lot of spare time to truly tinker with my designs. Anyways here is a proof of concept for my SSTO lifter, in the future I do intend to add/redesign features that will make this reusable and fully functional in orbit for positioning and attaching space station pieces.

What my design is essentially proofing is a way to attach and carry payloads to orbit without needing to fit test every little piece or create a crane to position and link up the pieces. Nothing annoy's me more than fit testing a piece 20 times to get it to be just the right height to link up with a docking port. My design utilizes landing struts to capture and hold payload as its being transported into orbit. The idea being, after the rocket has landed back at space port, new payloads can then be mounted to a rovers roof and driven to the rocket, centered then captured with the landing struts to avoid having to fit test heights. So if it will fit under the center rocket it will link up.

I did run into a number of initial problems with this design including a game related bug. However with minor redesigns I was able to fix all but the game related bug. As such you will notice that half way the rocket does change shape slightly by eliminating the large orange center tank in favor of an additional quarter tank on each of the outside stacks. This was done to lower the center of gravity and make the stability better. Of course I still have a slightly annoying game related bug that prevents me from speeding up time because it thinks its traveling over the surface. This bug also prevents me from saving while in effect, however I have figured out that once I achieve a stable orbit, I can release and immediately recapture my payload to fix this bug.

At any rate this is only the first step of a long road. Now to redesign a version that can land and be refueled. I also need to add thrusters and monopropellant fuel for orbital positioning, but I have some thoughts for that.

[Jasonden]

My design utilizes landing struts to capture and hold payload as its being transported into orbit.

Wow -- I would not have thought that would work. But you have shown that it clearly does! Very creative solution, I liked seeing it.

[gchristopher]

(Please tell me if this is getting off topic and I should move it to another thread.)

My project hit a snag.

Jeb got back from Minmus, and had some things to say about our reusable space fleet. (Starting with "REUSABLE!?!?")

So we told him: "Okay, Jeb, how about if you fly a plane to space that splits in HALF right down the middle? Does that sound fun?"

We eventually talked him into it, but we also had to promise to increase the payload capacity to more than the "wussy" 23 tons. We also had to promise to stop messing around so much with boring gantries.

So anyway, the Up Chuck and Unladen Swallow are now parked at a physics-safe distance from KSC so we can start launching with a totally new, even crazier reusable SSTO lift system!

(The more I learn about this game, the dumber my designs look.)

So, here's the plan: Much like before, a rocket/jet lifts the payload, and the spaceplane rendezvous with the rocket for deorbit. But this time the spaceplane is perfectly symmetric, so it can split down the middle and attach to each side of the rocket. The early failures on this one were GREAT. I wish I'd had the presence of mind to screenshot the debris fields. I was too busy laughing.

Here's a new 100% reusable launch system!

- The SporkLift rocket/jet lifter.

- The Hot Dog Bun modular space plane.

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This system has a bunch of advantages over the earlier Up Chuck/Unladen Swallow system:

- 40 ton max single payload capacity.

- More flexible payload, because the rocket is brick shaped, and the payload doesn't have to slot into a narrow area.

- The rocket lands upright! It can just drive itself back to the launch pad after landing. No messing around with righting a rocket.

- Pretty Stock, so far it's not intrinsically reliant on any mod. (Though I wouldn't want to fly it without automatic fuel balancing. That'd be a lot of clicking.)

- Killed Jeb at least twice.

The big disadvantage is the use of multiple docking ports to get a secure joint between the rocket and the half-spaceplane wings. You have to be extremely careful to get all three to dock, and it seems like it either works on the first try, or else you're in for 30 minutes of tedious re-docking. I'm 5 for 6 docking a wing on the first try.

Okay, I should probably get back to building the station, since now I have two reusable lift systems to choose from! Sorry it's taking so long to actually finish the challenge, but coming up with the reusable systems has been super fun. (And hard)

[LordFjord]

@gchristopher:

that is both brilliant AND beautiful. Very well done, that made my day.

I had my attempt to create something similar (side-docked SSTO) a few weeks ago here, however my concept failed as the docked craft were uncontrollable.

Could you make the craft file for the lifter and launcher public so I can learn from it? Would be great.

[Technical Ben]

(Please tell me if this is getting off topic and I should move it to another thread.)

My project hit a snag.

Jeb got back from Minmus, and had some things to say about our reusable space fleet. (Starting with "REUSABLE!?!?")

So we told him: "Okay, Jeb, how about if you fly a plane to space that splits in HALF right down the middle? Does that sound fun?"

We eventually talked him into it, but we also had to promise to increase the payload capacity to more than the "wussy" 23 tons. We also had to promise to stop messing around so much with boring gantries.

So anyway, the Up Chuck and Unladen Swallow are now parked at a physics-safe distance from KSC so we can start launching with a totally new, even crazier reusable SSTO lift system!

(The more I learn about this game, the dumber my designs look.)

So, here's the plan: Much like before, a rocket/jet lifts the payload, and the spaceplane rendezvous with the rocket for deorbit. But this time the spaceplane is perfectly symmetric, so it can split down the middle and attach to each side of the rocket. The early failures on this one were GREAT. I wish I'd had the presence of mind to screenshot the debris fields. I was too busy laughing.

Here's a new 100% reusable launch system!

- The SporkLift rocket/jet lifter.

- The Hot Dog Bun modular space plane.

http://imgur.com/a/FKs0w

This system has a bunch of advantages over the earlier Up Chuck/Unladen Swallow system:

- 40 ton max single payload capacity.

- More flexible payload, because the rocket is brick shaped, and the payload doesn't have to slot into a narrow area.

- The rocket lands upright! It can just drive itself back to the launch pad after landing. No messing around with righting a rocket.

- Pretty Stock, so far it's not intrinsically reliant on any mod. (Though I wouldn't want to fly it without automatic fuel balancing. That'd be a lot of clicking.)

- Killed Jeb at least twice.

The big disadvantage is the use of multiple docking ports to get a secure joint between the rocket and the half-spaceplane wings. You have to be extremely careful to get all three to dock, and it seems like it either works on the first try, or else you're in for 30 minutes of tedious re-docking. I'm 5 for 6 docking a wing on the first try.

Okay, I should probably get back to building the station, since now I have two reusable lift systems to choose from! Sorry it's taking so long to actually finish the challenge, but coming up with the reusable systems has been super fun. (And hard)

Wow. I just... This is "ThunderBirds" Territory right there. Amazing.

[Keldaria]

*stuff*

Wow, that is amazing and inspiring. I must admit I was starting to experiment with using a separate positioning tug with my rocket for handling the payload in orbit (the idea being to save monopropellant by not having to maneuver any extra tonnage in orbit), but this concept goes way beyond just having a separate craft for orbital positioning. A very elegant solution, It also makes me wonder if you couldn't transfer fuel back into the launcher in orbit to land vertically.

I do have a few questions for you,

1: does your plane have the ability to split and recombine while on the ground? Obviously after landing you'll need to resplit your craft, remove your launch stage and recombine them, how does that work?

2: are you able to remove your launch stage after landing, The long brace/docking port in the center seems like it would cause you problems when attempting to get the launch stage out, do you just fuel the launch stage and lift off to go up and over the plane wings?

All in all I love the concept, it maximizes the payload lifting capabilities by not having to carry systems for landing, then the landing system comes up under its own power and lands the launch system. Absolutely brilliant.

By the way, I've noticed a lot of you are utilizing regular plane engines rather than rocket. Obviously this carries the advantage of not needing to carry your oxidizer and they seem to produce a good amount of thrust for minor fuel consumption. However I've always had issues with using these in vertical situation and maintaining stability when they start to burnout in the transition out of the atmosphere. Can anyone give me any pointers on this, as I don't think I'll be able to maintain the payload capabilities I want with a standard rocket due to fuel weight and consumption.

[gchristopher]

Thanks all!

Could you make the craft file for the lifter and launcher public so I can learn from it? Would be great.

Definitely! As soon as I get the space station parts up, I'll post a full writeup and all the .craft files. I probably still made tons of beginner mistakes, though.

It also makes me wonder if you couldn't transfer fuel back into the launcher in orbit to land vertically.

Yes, that's probably way smarter, too, but I was dead set on strapping wings on a rocket in space, darn it! I guess having to only perform one landing is nicer than having to land a plane and VTOL component separately, maybe?

1: does your plane have the ability to split and recombine while on the ground? Obviously after landing you'll need to resplit your craft, remove your launch stage and recombine them, how does that work?

The plane has two sets of landing gear, one pointed forwards and one (slightly shorter) pointed sideways. There's a single sideways powered rover wheel under each wing half. After landing and separation, the forward-facing gear are raised and the sideways ones are lowered. That lowers the plane enough for the rover wheel to touch down, and now it drives around (sideways) like a very badly designed rover!

So the wings each drive sideways away from the rocket, then the rocket drives away under its own power (one small rocket), then the plane halves drive sideways to re-dock. That part turned out surprisingly robust and easy.

...do you just fuel the launch stage and lift off to go up and over the plane wings?

Ooh, oooh, or it could take off VTOL from between the wings and land nearby or, or... everything I do of that nature crashes. I tried.

You could launch like that, but loading the payload would be a pain and you'd still have to re-dock the wings.

issues with using [jets] in vertical situation and maintaining stability when they start to burnout in the transition out of the atmosphere

Others probably know better than me, but I just cut down on throttle and switch to the main rocket early-ish, instead of trying to milk every last bit out of the jet engines. After I've done the flight at least once by hand to prove to myself that I can, I hand it off to MechJeb.

One part that still has the potential to be absolutely horrid is getting all three docking clamps to mesh simultaneously. With MechJeb autodock flying one half, and me manually adjusting the orientation of the other half, it mostly works. One consequence of using MJ autodock is my RCS placement is pathetic. If I get into another repeated docking/undocking situation, I'm fully prepared to try cheating as described here: http://youtu.be/YsEHIn_ucIA It's too bad that there's no way to tell a docking port to "Just attach to the other docking port that you're clearly in perfect contact with."

[Hodo]

Kind of sad I just now see this challenge. As I had a few SSTOs that could do this with ease, and one that was designed to do just this.

SVO-17, the only one I have pictures of it actually loading and unloading its cargo.

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But SP-406 was my favorite, and heaviest lifter.

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It was more than capable of hauling 100 tons into orbit to a space station. If someone has the mods, they can use them if they would like, because unfortunately I can no longer run them due to the RSS+Realism overhaul mod.

http://forum.kerbalspaceprogram.com/threads/56945-Hodo-Creations-SSTO-craft-designs-and-files-for-those-who-want-them

[gchristopher]

The odd shape of SporkLift has meant a custom gantry for each payload, until I figure out a generic one.

Yeah, not totally sure this is a great idea.

[Keldaria]

Well, I've hit a few snags with my revisions. Landing in 1 piece is always a challenge and maintaining heavy lift functions with a ssto rocket is more difficult than I imagined it would be so I'm going back to the drawing board and starting a new career mode save in the hopes that going back to basics will lead to some new inspiration.

I'm still determined to make a respectable entry but it may take me a good deal of time to complete. Especially considering my limited play time during the week.

[sal_vager]

Great challenge SirJoab, let's see if you can get more entrants now that you've been stickied

[Jasonden]

Great challenge SirJoab, let's see if you can get more entrants now that you've been stickied

Whoohoo, stickied! Congrats, SirJoab!