Val

I have a few design guides that I use, for pure Rapier SSTOs that only go to LKO. For each Rapier you need: LF tankage: 2x Mk1 Fuselage or 1x Long Mk2 LFO tankage: 1x FL-T800 or 1x Long Mk2 or other equevalents, that add up to the same amount. Wing Area: 3 (2-2.5 main wing, rest for horizontal stabilizer) + Control surfaces + Vertical Stabilizer. Intakes: 1x Shock cone (lowest drag) This will allow you to lift 4.5 t to orbit comfortably. 5 t just barely. The 4.5-5 t is the rest of the craft and cargo: Cockpit RCS+Monoprop Cargo bay with cargo. Landing gear Batteries Power Generation Reaction Wheel Other things of note: The only recommended surface attachments are, Wing parts (incl. Airbrakes) and Retractable Wheels. Fuel tanks are OK, if used to mount an engine. RCS and Radiators may be needed. Everything else goes in a cargo or service bay. As little control surface as is necessary. On many of my single Rapier designs i only have 2 control surfaces. Combined Roll and Pitch in a V-tail or Elevons. I always mount wings with a little upward angle, so I can have positive lift, even with the craft at zero degrees pitch, at high enough speed. I do it mostly to minimize drag around and right after Mach 1. Because it's better to have only the wings at an angle to the airflow, than the whole craft. I aim for neutral lift around 375 m/s, at sea-level. At 9 km this gives neutral lift around 600-800 m/s. Once I've built my SSTO, I evaluate it's performance using quick tests, that I've found to work for me. It takes a maximum of 4 minutes to test the basic viability of a new SSTO. That is not to say, that an SSTO which fails my tests, can't get to orbit. But it will probably take much longer than it needs to and probably uses more fuel than needs. Which brings me to the ascent profile. I don't use the standard, slow climb to 10 km. I fly pretty much level right off the runway and don't start climbing until I hit 450 m/s. I've found this to be the most efficient ascent for my designs. Especially the heavier ones, many of which could not climb past 5 km with the standard ascent. I baked the tests into this album. Craft file In general I prefer combined Rapier/Nuke SSTOs. I find them to be much more efficient than pure Rapier. They use a very similar ascent profile. There's a bunch in the SSTL album in my signature. Mostly made from Mk1 parts, but there's a few made from Mk2 and Mk3 parts, also. Here's a proper Rapier/Nuke SSTO: G+ post (with craft files). Although that one is a bit overpowered. It doesn't need a sea-level acceleration. It can accelerate through a shallow climb.

When I flew it, it felt more like, too much wingspan, relative to the vertical stabilizer.So you can try one these 3 things: Move the vertical stabilizer further back. Put a bigger vertical stabilizer on. Make the wingspan shorter.

When I replaced it with a fresh wheel from the part list, the craft didn't veer left any more. You're welcome They aren't needed, but can be helpful, if you dip a wing during landing. Uneven terrain or because the craft is a bit hard to fly.

I laughed so hard my cats ran.

The tail wheel was definitely not put on straight, even though it may have looked it. I replaced all the wheels, to make sure they had no inherent adjustments errors. And except for the tail wheel, mounted them differently. The main load bearing wheels need to be very close to CoM, because if any noticeable load is placed on wheels far from CoM, then you get veering. Craft file Edit: Forgot to mention. For stability, the main wheels are actually attached to the fuselage, not the wing. They've been moved with the gizmo to look like they're mounted on the wings, so the wheel base is a little wider, than if they were flush against the fuselage. - - - Updated - - - Oh, I did not know that. Thanks.

Built a Single Stage to Laythe mission. And circumnavigated Kerbin in the Nano Jet. Cutting it close. Only a few minutes of fuel left after a 2 hour flight.

Mission update: I got a U-6 Spirit Mk.3 to Jool with 4.2 km/s dV left in the tank, using PLAD's K-E-K-K-J route. Though, I'm not nearly as effecient. Still costs me ~1.3 km/s dV. But it was a big improvement over the 2.3 km/s dV a direct burn cost me on the previous attempt. Unfortunately I couldn't land at Laythe. No matter how I tried to aero-capture, either the Mk1 Pod kept exploding or I didn't slow down enough. So I gave up... again. I'm now trying with a Spirit Mk.6 which has more wing area for aero-capture and more radiators to keep cool. I'm using PLAD's route again, but I didn't hit the windows that well, so had to improvise and use a different 2nd Kerbin flyby, to hit Jool. And then I arrived a bit fast at Jool, so had to use a 32 m/s Jool PE retro-burn in combination with a Tylo gravity assist, to get captured. And i haven't had time to do more, so haven't tested the upgrades on the Mk.6 yet. Misc.: On a side note, I started wondering if I could build something that could bring some cargo to Laythe. And then this surprise happened. A Mk3 based SSTL with 9.5 t cargo and 4.1 km/s dV in LKO and 0.26 TWR. Or 5.1 km/s dV and 0.27 TWR with empty cargo hold. I was just surprised a viable SSTL could even be built using Mk3 parts.

Impressive feat, PLAD. Such a small ship. So little dV.

That is a very nice looking craft. And impressive Dv too. The TWR gives me shivers though

Thanks. Took me every evening since my failed Laythe attempt to work out that design. Went trough a lot of iterations to figure out especially: Optimal placement of each component, to keep thrust through CoM and keep the CoM from moving too much when fuel is drained How much wing is needed and at what angle to the body, to keep drag as small as possible while passing through the Mach barrier. Would probably have saved a lot of time doing this with a 2:2 engine layout. Would have been so much easier to get thrust through CoM. A 1:1 layout is much like a rocket with boosters only on one side. Kinda like the Space Shuttle. Some concepts I tried. Actually. I may give some new 2:2 or 3:3 designs a go. With all that I learned, I think I could reach 6 km/s dV and TWR > 0.3 in LKO. A single Rapier should be able to lift that. Hmm. With nukes you don't need Oxidizer on Laythe. I could get up to 1600+ m/s Airbreathing with Apoapsis at 75 km. I wonder if that would be enough for Ions? Heh. I was going to suggest just that.

I think the problem with Ions is that you have many open stack connectors. It creates so much drag, that you need an unreasonable amount of Air Breathing thrust to lift it to orbit.How much does your ship weigh? I managed to create some pretty awesome (if I say so myself) designs where a single Rapier can lift a craft with a starting weight of 26.8t to orbit, weighing 18.6t once in orbit. SSTL U-5 Dart Mk.5 Does your ship weigh more than that to require 2 Rapiers?

Gratz! Awesome job. And great pictures and captions. I've not tried again, yet. Been working on my ultralight 1:1 designs. And now I'm going away on vacation for a week, so won't be doing anything KSP until I'm back home.

If you have enough stages, that you can drop one and still have something left, then by definition, it isn't single stage Even if you pick the other stage up later.

Yeah, I should have explained what I meant with low drag builds.And to add to that: Avoid radial attachment, except for the 2 necessary ones, wings and additional stacks. That means Struts and Fuel lines, too. [*]No unused stack attachment points. I do make an exception for Nervas, because the auto-fairing can cause problems. Oh. I'd completely forgotten about the Mk1 Pod. I originally discarded it because, I 'needed' my crafts to look a certain way. I don't think wet wings reduce drag directly, but maybe indirectly, because of reduced part count. Is that what you meant? The difference between Mk2 fuel tanks, and Mk1s + wingparts for similar lift, is very small. 1% in favor of Mk1+wings, according to my calculations, which may be wrong.But, if the above assumption about less parts = less drag, then maybe there's no difference at all or maybe it favors Mk2. I guess it depends on how much part count affects drag, and is really only applicable in edge cases with extreme fine tuning of wing area, which is only possible on larger builds, I guess. Anyway, you gave me an idea for a new 1:1 design. Thank you

Light weight, low drag builds. No RCS, cargo or other parts that aren't absolutely necessary for the mission. If you interested here's: An example SSTO craft with instructions. At least 3750 m/d dV in LKO if you replace the cargo bay with a long Mk2 LF tank. A long, boring and un-commentated video of launch and landing of a similar, but simpler to build craft. But it shows what speeds, altitudes and climb angles are used to get to orbit.

Mine have TWR between 0.29 and 0.41. (I've added TWR data to my album now) Mission Update: I didn't make it back to Kerbin. I had ~1450 m/s dV in Laythe orbit, which wasn't, too bad. But a bit of butterfingers and bad decisions regarding gravity assists, meant I got stuck missing around 10 m/s dV to hit Kerbin atmosphere for capture. My last good save was Laythe orbit and it was too late to try again. But with everything I learned from this trip, I think, I'll start a new attempt, with a smaller ship and less dV. Will probably try with the Lightning Strike Mk.2.

You're very welcome. I'm glad it was of use to you. I only made it, because, like most people, I like to boast about my accomplishments It's very rewarding when someone actually finds it interesting. So thank you very much for that Anyway, I'm about to attempt my return journey. I guess I don't have to worry about taking off from Laythe then. It's just a question of whether I have enough dV left and can survive arrival at Kerbin. Will report back in a few hours, I hope.

I made it to Laythe, using the 5.2 km/s dV, M-5 Space Hustler. Had a bit over 2.6 km/s left, when I landed at Laythe. Will be interesting to see if I can get off Laythe without Oxidizer, and how much dV is left, if I can. Craft file

For the past few days I've been working on designs for a "Single Stage to Laythe and Back" challenge. I quickly gave up on trying to do a design with Ion engines, so all my designs so far are a combo of RAPIERs and Nervas. Ranging from 1 RAPIER and 1 Nerva, to 8 RAPIERs and 4 Nervas. I'm hoping 4.5 km/s dV in LKO is enough, with aerocapture and a little gravity assist. Now I just have to select one and go try the challenge, and I hope I don't burn up.

Thank you Here's my first time reaching Orbit with a 3:3 Rapier/Nerv setup. 5.1 km/s dV, but only 0.39 TWR, if MJ is right. KER says 0.5, but 0 dV. Not sure which is right. Hoping to improve it. It's also reaching a size now where, I need to use struts to keep it from wobbling. Didn't use struts on any of the previous designs. The look is inspired by the XB-70 Valkyrie.

I made a new design. Still with 3:2 Rapier/Nerv. 5.5k m/s dV, but only 0.3 TWR at LKO. Inspiration for the look should be obvious. I call it SSTL A-12 Ghosthunter. I also tried 2:2 Rapier/Nerv layout, but I couldn't get enough dV without overwhelming the Rapiers. Will try making some designs with other Rapier/Nerv layouts. Then select the best and try to complete the challenge this weekend. More pics http://imgur.com/a/nWUaf

Interesting read. Thanks. Going to see if I can improve my SSTL with this new info. And here I was just using Shock Cone Intakes for that B-58 Hustler look. Seems they were actually the best choice, too. Woot.

If that is the case why don't they show in the Staging?

BTW, what are those cones sticking out of the Rapiers?

Thank you Propulsion is 3 Rapiers and 2 Nervs. Total mass at launch is 49.61t The craft file. Take-off and accelerate with nose 5o above horizon. At 200 m/s nose up to 10o and continue accelerating. At 400 m/s nose up to 15o and keep it there until coasting to Ap. Should hit 830+ m/s at 10km. At 20km you should be going at 1200+ m/s and be very hot. Engage Nervs. When Rapiers run out of air switch Mode. Rapiers should boost you from ~1350 m/s to ~2050 m/s. Keep going on Nervs til Ap is at 81km. Coast to space and circularize. Should be around 80km. I'm using Rareden's Real 8k Skybox for Texture Replacer Monitor is LG 34" and, yeah, I'm very happy with it.