Syvwlch

Thank you! Going by the name of the craft the eighth launch is the one that made it to the Mun. Took maybe a day of off and on tinkering? The tweak it took me a while to realize I needed to do was sizing the two canards so that they did not induce a roll when used to raise/lower the nose, especially on takeoff. Wasted some time believing it was a thrust imbalance.

They also update automatically if you are in Move mode. Not sure why, but when I'm working on an SSTO tweaking CoM position, I always do it in Move mode. EDIT: Specifically, if you change fuel load of a tank while in Move mode, the CoM moves in real time.

Yup, I see this regularly. In my case it's most often the small RTGs or any docking ports.

Yup, have a base module landed near the Minmus polar anomaly in the same state of Schrodinger's Kerbal. The crew are safe as long as no other craft goes near them or I don't take control of that module from the tracking station.

Well, you win some, you lose some. Night launch went off without a hitch.,, even tho our engineers forgot to stow the deployable antenna before rolling the launch stack out. The pilot barely complained about the rocket's tendency to pull south on ascent. Sticking with the night theme, a 3+ minute burn in the dark got us our Jool encounter. A small mid-course correction burn got us all lined up for a beautiful low-inclination capture at Laythe... ... but once we entered Jool's sphere of influence, our solar panels refused to work. Rolling back the mission telemetry to a prior save shows we had decent power generation outside Jool's reach: So this mission plan is going on the back burner for now. I could redesign with other power sources, but that would put a time limit on the service life I'm not willing to put up with. I guess I will pivot to a single launch with RTGs to get the Stowable SSTO to Laythe, for now? Or perhaps work on the Val level of the Asymmetric SSTO challenge? We'll see!

Landed an (asymmetric) SSTO on the Mun for another challenge: only bug encountered was a tendency for the gear to fall off when loading a save or using timewarp below 20km altitude… so I was very motivated to get the landing done in one take (took two).

Worked on a modular space station system for Laythe orbit, including: A hab module with three medium and two small docking ports which also doubles as a Jool-class comms relay An orbital unmanned space tug (green, for monoprop only) Various 35 to 50 ton tanks (yellow is hydrogen, agency colors for methalox, and orange/white for methane) A SWERV-based interplanetary ship EDIT: I think I can do it in three launches and three trips to Laythe by the interplanetary ship, which I've beefed up the fuel capacity of. I've combined the methalox and methane storage into a single tank, which should be enough to refuel the small SSTO a dozen times, so plenty of exploration of Laythe before we need to do another milk run.

Today I landed an Asymmetric SSTO on the Mun! For reasons! Beside having fun, I'm learning a lot about SSTOs with this challenge, mostly about things that just happen automatically with symmetric designs but no longer do when you throw that out the window. Not sure that will ever come in handy but I'm better a debugging a design than I was before I started doing this for sure. Today's big lesson was that when you have asymmetric placement of control surfaces, it's not enough to size them such that the CoL is placed where you want it... you also need to size them such that when they deflect they produce a balanced control force. My first version of this SSTO would roll right during pitch up maneuvers, e.g. on takeoff, until I made the right side canard larger, which required tweaking all three wings to get the CoL back where it needed to be. You don't need to get it perfect, but within what the cockpit's torque can handle.

Jeb level entry - Landed an Asymmetric SSTO on the Mun! Again, barely made it (definitely don't have enough to get back to orbit) but it counts... Elbas volunteered, I swear! Here are (large) screenshots showing we started with 2km/s dV in LKO and where we landed with less than 100m/s dV left: This is a complete rebuild from scratch, using some larger methalox tanks as a starting point: Here's our target! Caught a weird double intercept but since we captured on the first pass, it remained theoretical. Looked at the planned landing spot from orbit before initiating descent. Caught Kerbinrise on our way down! I managed to get one screenshot during the actual landing because I was rather busy with the usual SSTO vacuum landing: zero velocity relative to ground a few meters up, and pitch nose down to land on gear.

Yup, the outboard pod is radially attached and then moved into position. All three Rapiers are parallel to main fuselage, but the thrust limiter on the outboard one is adjusted down to move the position of the thrust vector in line with CoG. The various wings are sized and placed such that the CoL is also in line, and only slightly aft of the CoG. Main difficulty is finding a fuel tank layout that does not move the CoG as either fuel type drains (methalox and methane). I basically laid it out so the outboard pod has 1/2 the number of tanks and roughly half the dry mass to keep things simple. As fuel drains the ratio of the vehicle's mass in either part stays the same and the COG doesn't move . The only control surface tweaking is reducing the authority to keep SAS from oscillating which at best is inefficient but usually results in a tumble and explosion.

After a little bit of tweaking and adding some more methalox tanks, got to 1km/s dV remaining in 80x80 LKO: That main fuselage is starting to look ridiculously long and you have to baby it a little more off the runway, but still flies very sedately.

Nooooo!

Here's my entry for the Bob level (flown by Bill, oops): Wheels up Saying goodbye to the KSC Mode switch altitude and speed Coasting to apoapsis Circularization Barely made it but it counts! Note I have waaaaay too much methane on board, so can probably improve the dV in LKO by just leaving 3 tons of CH4 at the KSC... but not enough to attempt the Jeb level challenge.

Today I checked that the Stowable SSTO can handle a rough field landing after ascent and deorbit burn (so fairly light). Took a few tries to work out the procedure, but trimmed out to glide at 60m/s it came down to a three point landing and a combo of brakes and SAS to keep the nose pointed the right way got us stopped and in one piece. I opted to work on this rather than a launch stack to send this to Laythe because I'm finding the VAB much harder to work with than before patch 2 with multiple assemblies. EDIT: I also cleared the Bob level of the Asymmetric SSTO challenge:

Thanks for #2, will try it tomorrow!

I have one with a single rapier that is performing the same after the patch (500 m/s dV left once in LKO) as before. The ascent went exactly the same for what it’s worth.

Lembas Kerman is thinking about stealing Lembree's seat in the Stowable SSTO prototype... No honor amongst test pilots? In related news, today I learned that if you EVA the pilot on the runway and revert to VAB without getting them back into the cockpit, the next kerbal in line gets assigned the seat in the VAB. I just had a vision of the two test pilots arguing over whose turn it was. As far as the spaceplane is concerned, the engineers added a small docking port on the back aft of the cockpit (belly installation led to a jittery Kraken-adjacent dance when the gear was retracted) and with the latest tweaks to design and ascent profile we made LKO with 650m/s to spare. Lembree vehemently denies this is due to Lembas being at the control during that test flight.

Downloaded patch 2 and then talked Lembree Kerman, our trusty SSTO test pilot into trying to get in and out of the Stowable SSTO without a ladder. She was, at first, skeptical but came around in the end. Turns out you can retract the gear and then get in and out at ground level even in Kerbin's gravity. You can also step up onto the canard which was lowered and from there clamber up onto the nose and over the cockpit. Why were our engineers so keen to get rid of the ladder? On this tiny craft a retracted ladder on the port side was enough to pull the nose northwards on ascent requiring pilot input to maintain zero inclination*. Two ladders made the thing fly straight, but at some significant cost to dV in LKO. Subsequent testing showed that doubling up on the air intakes was worth the drag penalty, as the rapier delivered more thrust in the final moments before mode switch. This version is much easier to fly & has better performance: consistently reaching LKO with 550m/s with some extra methane for landing. Lembree was quick to agree that not everyone who'd get to sit in this scorching hot seat would have her skills, and gave this design two thumbs up. * Altho inspection of mission photographs indicate those test were run with the starboard wing mounted upside down. No one at the VAB has stepped forward to claim credit for that particular SNAFU.

Yup!

The outboard tanks start out radially attached to the cockpit, and then I move them outwards. They look like they’re hanging in mid-air until I shape the wings/canards to meet them. I almost never use struts except for the top of SRBs on first stages. Even the 80t SWERV+Whiplash doesn’t have any. What I do is avoid chains of attachments: the landing gear, the wings, the outboard tanks, and any other parts that aren’t in-line with the fuselage are attached directly to it, and then moved into position. This seems much more rigid and solid than having gear attached to outboard tank attached to wing attached to fuselage, and often makes it easier to tweak placement to align the three centers of mass, lift, and thrust.

Explored a few different ways to add more tankage in the right CH4/Methalox ratios on the Stowable SSTO, and the only efficient way was to move the small tanks further outboard so I could move them back up to the CoG without blocking EVAs. Medium inline tanks were too much for this layout. Some mild residual clipping with Elbas' helmet here but it works. Bit of a Star Wars look to it now, somehow? So it still fits in the XL cargo bay, weighs in under 8t wet, and gets into LKO with 500m/s left, which feels like a decent safety margin. (Previous version only had 150m/s left in LKO.)

That happens to me all the time. I'm in LKO with X amount of dV and it's only then I wonder where I could go today. Your space station looks amazing, btw!

I could not either until I read the pinned post in the Craft Exchange forum which includes instructions on how to use Imgur. Give that a try?

Got curious about what I could make with a single-seat cockpit and a single Rapier engine, and whether it could fit inside an XL cargo bay... so I made an SSSTO: a Stowable SSTO. Lembree Kerman took her up for a test-flight... Makes it to LKO with enough dV left to RDV with something but not much else... but it reaches 1.5km/s on 3/4 throttle so I think there's room in the thrust budget to bring some more fuel and/or suffer a bit more drag.

Still learning my way around minimizing drag but latest mini-breakthru was realizing giving each Whiplash its own nosecone was way worse than using a couple four-way coupler pieces behind a shock-cone and the methane tanks. SAS responded with an irritating but not lethal small yaw oscillation, but my dV at LKO jumped from 5.3 to 5.9 km/s. Also found that the game doesn't seem to care about the wings' planform much, so I placed the resulting jet-pods where I needed to keep CoG in the middle of the hydrogen tanks and shaped the wings to plausibly hold them. The negative dihedral helps to tweak the CoG and CoL's vertical position so they both align with the CoT. As tanks drain (either type) the CoG creeps forward a little and doesn't move vertically. The Whiplash is worth it, but the need to use methane rather than methalox tanks is rather limiting in what shapes you get to play with! Result is a docile craft that handles well full or empty, taking off full easily at 100m/s and landing empty at 80m/s. It ascends to orbit with only throttle adjustments once initial pitch is set (15 to 20 degrees seems to work fine). Switch to SWERV happens at 15-20km altitude at ~1.2km/s where full thrust keeps apoapsis at 1 minute for a nice smooth efficient upper-atmosphere phase. As stated above, I circularized at 80km with 5.9km/s dV left. A trip to the orbital fuel depot to top up (about 6tons of hydrogen) would get us up to 7.5km/s according to the VAB but I have not tried that yet.