cantab

Well, more what did I do yesterday. Some rather tricky docking. Note to self: Drop tanks being transferred from ship to ship should have TWO docking ports.

On framerate, virtually all major movies are produced and shown at 24 fps though with each frame projected two or three times to reduce flicker, despite most cinemas now having digital projection systems capable of showing 48 fps. I think that's reason enough to believe that above a certain point framerate doesn't make much difference.

I think you should start a Challenge of this, if there isn't one already. I'll definitely give it a shot.

Vertical to 10km, 45 degrees until apoapsis attained, then circularise at apoapsis isn't exactly efficient, but it's not that wasteful either. In my experience the bigger danger is going too shallow. You should be using around 850-950 m/s of delta-V for the trans-Munar ejection. Certainly not more than 1000, if you are you're doing it wrong. Assuming you use the 1-man command pod, one FL-T400 and any of the LV-T engines will do you a Munar orbit and return, even if you're taking a fair few Goo Canisters. Just get that into LKO without using any of its own fuel and you're set.

I don't recall if the Whack uses it, but MechJeb can make launching massive things tolerable. It's not fussed by the slowdown, so just wait for it to do its thing. Once in orbit you'll typically have dropped many of your parts, and once far enough from Kerbin performance can improve further.

Three. The three that were passing closest to Kerbin when I first checked. All the rest I detracked. And I haven't had any new unknowns spawn in a little while. How often should they come?

The lights, at least, are reasonably well reported.

Nice work! How have you got the centre section attached, it looks like you managed to clip it into the asteroid.

Going by the delta-V map: 4550 m/s to reach LKO plus 1680 for the ejection burn, giving 6230. That's quite high, but should be within what a three-stage launcher can do (remember the Saturn V used the third stage for trans-lunar ejection.) The gotcha is that that's in an optimal launch window, but then waiting for said window isn't The CSM then needs 5130 m/s to circularise at Moho, and later depart Moho back for Kerbin. 2200 of that needs to be done with the LM as payload. That is again quite high, but I believe doable, for a single stage; the limit with a 390 Isp engine and traditional tanks is 8397 m/s. Perhaps not in the spirit of the challenge but still perfectly viable and I feel reasonable would be a two-stage CSM. The LM needs 2800 m/s. Entirely reasonable - Tylo needs much more. Make no mistake, this is going to need a big rocket. Not Whackjob big, but still big. You could reduce the delta-V requirements with an Eve gravity assist, at the cost of a longer transfer and probably waiting ages for the launch window. (You could reduce them more with repeated gravity assists, but then the time gets unbelievable for a manned mission.)

There's been plenty of discussion of save migration from .23 to .23.5. It's mostly straightforward but there are some gotchas that may come up.

I'm astonished that thing held together for so long. I'm starting to think Squad overdid it just a little with the strengthening - and underdid it with stiffening. Anyway, looks like you just need more boosters round the outside. To distribute the thrust, of course.

@Streetwind: To add, the delta-V for a single stage approaches a limit, since the mass ratio can never be better than that of the tankage. For KSP that's 9.8 x ln 9 = 21.5 times the Isp with traditional tanks, and 20.6 times with ARM tanks. More staging is thus encouraged with heavier tankage. IIRC Kerbal tankage is heavy, akin to that for LH/LOX, despite engines having lower performance closer to RP1/LOX.

I've used it. As mentioned, it's suitable for augmenting a Mainsail. It won't make the Isp any worse, and it's one part versus at least three if you want to radially mount a regular engine (engine itself, fuel tank or similar to mount it on, and fuel line to run it off the main tank).With the Mark 55 and for that matter the 24-77, you're "paying" for the convenient form factor. Unfortunately it's too big a price for landers where they'd otherwise be good. I wouldn't mind seeing their vacuum Isp's buffed, but with relatively low TWR to take account a bit of the weight savings by not needing radial attachment structure. (Actually the 24-77 has *high* TWR if Wiki figures are right: Excluding ARM engines, it's 3rd after the 48-7S and the Mainsail.)

On the roof of the VAB?

Absolutely agreed. As for general rocket performance If we're talking about interplanetary ships, delta-V is king. More dV means you can go more places. Not enough means you'll get stuck. If we're talking about launchers and landers, enough delta-V and enough TWR are givens for the job. It either has it and can succeed, or doesn't and will fail. For launchers in theory payload fraction - how much of the launch mass is the payload and how much is the launcher - is the main measure of performance. If you strive to make efficient rockets, that's what you should be going for. in practice though in KSP mass on the launchpad is free. (Even in the real world fuel on the pad is cheap). What is arguably more important for playability and enjoyment of the game is payload per part. A launcher with fewer parts will let me send up a bigger, more complicated, and more satisfying ship with less lag and thus less real time taken. That's why my next launcher is going to use the ARM tanks, even though they have worse tankage than the Rockomax and FL-T ones.

I've been playing stock or nearly stock so far. I've only used two mods. Engineer Redux is a big help and I still have it. I wouldn't build a ship without knowing the delta-V, and it saves me crunching the numbers by hand. ShowFPS I used for performance troubleshooting but don't need it now. In terms of what I'll go for next, I feel I should get FAR and presumably Procedural Fairings or similar before I start serious efforts at spaceplanes. Maybe Firespitter I think it is along with that, for some more options for regular planes. I'm not sure I want my old rockets to be broken though. And certainly I may consider MechJeb at some point, along with Kerbal Alarm Clock and other usability mods. .23.5 has held off my desire for PreciseNode though. Resource exploitation mods such as Kethane and Extraplanetary Launchpads I don't expect getting for a longer time. Probably after I take a big break from KSP and return (which is bound to happen sooner or later).

Fuel tanks make good dummy payloads. There's nothing but mass there, so you can be sure all the control is from the launcher itself. Plus you can then feed the test payload fuel to the top stage engines and ram it into the Mun at ludicrous speed. The only thing to watch for is length; real ships of the same mass might be longer and thus harder to handle. That caused an issue when launching my asteroid tug. If I'm building a launcher, I'll usually place a payload fuel tank first, then build the launcher below it. That way I can drop the launcher as a subassembly: IIRC you can't drop your entire rocket as one. I use KER to check my stage TWRs and delta-V. If you're doing it manually, a viable shortcut is to stick what you have on the pad and get a mass readout from the map view, saves you totting up all the parts individually. Then subtract the fuel and oxidizer in the tanks you're using; make sure you don't count the payload tanks by mistake.

10 VABs high...By the Kraken, this I want to see.

I don't think this is correct. Two versions of the NERVA were tested on the ground, both making sustained firings. I believe that even on the ground they had higher Isp than chemical rockets, and the low sea level Isp in KSP was done to balance them.

Point taken. I was meaning rather that the Shuttle was unusual in being off-balanced, not in using the core and boosters in parallel.As for KSP, well I think - but haven't proven - the answer is simple: If your core has good TWR and you're using the boosters to give you more delta-V, you should let the boosters burn out before igniting the main engine. That way you're using your low Isp boosters to lift your higher Isp core. If your core has low TWR and you're using the boosters to give you more thrust, then you should ignite the core and boosters together. Otherwise when the boosters burn out the core STILL has low TWR since it hasn't burnt up any fuel and you'll start losing speed.

Thanks for the advice everyone. I'll try some of them my next launch.

Reaction wheel tests Test ship: The four fuel tanks are full. We have a pair of reaction wheels at each end, and a pair in the middle. We also have two batteries in the middle to ensure we can power the reaction wheels fully. I threw it up on a Skipper with fuel-hack, in case you're interested. Method: For each combination of reaction wheels, the following is done. SAS is disabled, and any residual rotation killed with a burst of timewarp. Full pitch or yaw in one direction is applied for 2 seconds. Letting the ship spin freely, the time taken to make one full turn is recorded using the in-game MET. The RGU's torque is off at all times, to not confound things, and testing is all in space so air drag isn't a factor. Results: [table=width: 500, class: grid] [tr] [td]Configuration[/td] [td]Time/s[/td] [/tr] [tr] [td]2 in middle[/td] [td]39[/td] [/tr] [tr] [td]2 one end[/td] [td]38[/td] [/tr] [tr] [td]1 each end[/td] [td]37[/td] [/tr] [tr] [td]1 end, 1 middle[/td] [td]38[/td] [/tr] [tr] [td]1 end[/td] [td]74[/td] [/tr] [tr] [td]1 middle[/td] [td]71[/td] [/tr] [/table] Additional notes: During all turns, the ship rotated about its centre of mass, geometric centre, and root part (which are all in the same place). At no point did the batteries run anywhere near dry. Conclusion: The results speak for themselves. In terms of speed of turning, distance of the reaction wheels from from the Centre of Mass is not important. This matches what was reported by KvickFlygarn87 and the results from Kashua's torsion pendulum setup. It is I believe contrary to actual physics. Halving the amount of torque approximately halves the time for the turn, as expected. The way in which reaction wheels act to deform the ship remains to be investigated, as does whether KSP properly implements moment of inertia. The latter could be tested with a ship like mine but with two tanks full and two empty, shifting the fuel for different tests.

For RCS, yes, certainly if it's balanced (RCS at each end) and possibly even if it's not, because they're capable of a certain linear force that then gets used to create a torque. For reaction wheels I believe no, because they give torque directly, around the point they're located at.

This is my Chamberlain "space bus" on top of its launcher. It has wings so I can glide it to a controlled landing site, and it does glide fairly well at low altitudes. Launch, though, is a problem. Straight up is fine, but attempting to make a gravity turn at 10km leaves the rocket wanting to pitch head-over-heels. For this rocket and payload, gravity turn happens while still on the first stage. I can make a late gravity turn where the air is thinner and keep it under control that way, the launcher does have the delta-V to spare, but that still doesn't feel ideal. Are there any better solutions, besides "Take the wings off" and "Build a spaceplane"?

It's an unusual case though. The Shuttle would need its main engines firing to stay balanced.