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[BigD145]

Ah, so, has anyone actually done it? Or did they try only to have the fuzzy numbers break it?

Looked to me like it is possible but nobody demonstrated it ingame. It would take some maintenance too, to adjust the orbit every few cycles

Lack of N-body gravity makes it easier but rounding errors make it harder. You'd have to babysit it quite a bit and babysitting it alone adds more errors as you activate physics while piloting or approaching.

[miauw62]

So I finally gave mechjeb a try, I both want to praise it and curse it at the same time, while its quite efficient at some things, other things its a bit inefficient, namely the landing from orbit, sure it can land almost strait back onto the launch pad from orbit, but it tends to fly strait over the target then enter the atmosphere at 2500 m/s at -70 degrees....while the spacecraft was mostly fine, seeing radial attached bits get blown off due to heat is always annoying. I did a test of going from orbiting minmus at 10 km, transit to kerbin, then set it to land while on the way to kerbin, it burned through 1k delta V and went on an escape trajectory...so I manually landed it. One thing that did help was the predicted landing, which let me land the rocket within 20 km of the space center.

I love mechjeb for teaching me how to do gravity turns.

[Dutchling]

are you supposed to start gravity turns at 3km?

either that or my mechjeb is borked. :<

[Putnam]

As of 1.0, you're supposed to start gravity turns at about the instant you take off, or else you get ships that flip.

MechJeb's gravity turn method pre 1.0 was completely awful for anything approaching realistic aerodynamics... like 1.0.

[Dutchling]

well, i get the flip part right.

usually mecjheb was able to just continue on after a loop or two, but it's still kinda annoying.

[forsaken1111]

If your rocket is flipping, you have a design flaw.

[Dutchling]

ill post a pic in a sec

[forsaken1111]

ill post a pic in a sec

Include your TWR per stage as well please

or even better, the craft file + a list of any mods you have

[Dutchling]

I use MechJeb and some (fairly sure the) weapons mod.

Spoiler (click to show/hide)

Ship is carrying a module to my space station. That's the large batteries and the part between, underneath that is a manned part to switch crews, this part is supposed to land back at Kerbol. I added the cones recently hoping it would add some stability to the ship, no idea if they even serve a function is KSP.

I guess I could try to increase the height of the side parts to make it less top heavy?

[nogoodnames]

No, you want it top heavy, and maybe add some fins at the bottom. Your rocket should fly like a dart, weight at the front and drag at the back.

And nosecones are now important for reducing drag.

[Dutchling]

maybe add some fins at the bottom.

the moving ones or the sturdy ones?

[nogoodnames]

Either. Since you have a cluster of mainsails, you should have enough control from their gimbals so just straight fins are fine, but more control won't hurt. You just want the center of drag behind the center of mass to keep the rocket pointed along its prograde vector.

[forsaken1111]

Height looks fine. Add some winglets to the boosters and some more to the main body, all at the bottom.

[Dutchling]

Wings fixed it.

I have an issue with "stowed" engines though. Three of the four side-engines you can see on the earlier screenshot won't activate and their status is "colluded". Any idea what is causing this?

[nogoodnames]

That's a really annoying bug with fairings. For some reason you're not allowed to activate engines while they're in fairings (as an aside, that they decided to just take that option away from the player pisses me off more than any of the actual 1.0 bugs) and sometimes it improperly registers engines as being inside fairings. You might try fiddling with the engine placement, but the only surefire solution I can offer is to replace those fairings on the boosters with actual nosecones.