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[BigD145]

Your RCS need to be balanced around your COM.

[Sean Mirrsen]

It doesn't "need" to, really. It's a help if it is, but you really only need your RCS to have sufficient control authority for SAS to keep you level.

When you're on final approach, switch to fine controls mode. If you're still overshooting with fine controls, you may need to pack less RCS thrusters.

[BigD145]

For anyone that is having trouble, yes it needs to be. Otherwise they'll likely drift off target without really undrstanding why.

[Leonon]

One trick when you're intercepting after getting close (20km-ish) but before you start docking (500m-ish) is to not quite point straight at you target as you burn. That way if you overshoot nothing explodes.

This also lets you safely get closer using your main engines (assuming you can flip around in time) than you otherwise could.

[nogoodnames]

The quest for the SSTLAB continues! Today I built a simple 30 tonne LF-only SSTO and flew it to Laythe. It got there with 52 units of fuel left, which is kind of amazing since at full fuel its LV-Ns could only produce a maximum of 4350 m/s. I have severely underestimated the capability of the RAPIER's jet mode.

I've also calculated that I would need about a 4:1 ratio of fueled mass to empty mass, which seems pretty low. I'm actually kind of surprised no one has done it in 1.0 so far to my knowledge. From what I've seen, the optimal TWR values are around 1.2 for the RAPIERs (assuming an average thrust of 200 kN) and 0.5 for the nukes. This seems eminently doable. Soon I'll calculate exactly how many fuel tanks and engines I'd need and hopefully get a prototype built.

[MarcAFK]

I think I'm getting the hang of this whole heavy lifter concept.

Spoiler (click to show/hide)

What's that payload up there? Oh just a single USI Kontainer, nothing special.....

Spoiler (click to show/hide)

Full of Uranium, 714 Tons of it, and 10 tons for the Kontainer.
For reference the First stage has 1800 tons of LFO and 9 Mammoths,,Stage 2 has 384 tons of LFO in 12 Boars, Third stage 800 tons with 9 Rhinos, and the final stage has 225 tons of Fuel and 40 Nervs.
Every stage but 1 has a TWR less than 1 when it's first fired, First stage has a mere TWR of .70 at sea level but after lighting up the boars this soars to 1.69, after 47 seconds when the boars are finished the First stage continues with a TWR of 1.25.
When stage 2 is lit the TWR is a mere .85, but as acceleration remains high both altitude and speed continue to increase and in a few seconds the decreased fuel and higher altitude allows TWR to clear 1 again.
When the final nuclear stage lights off the rocket has reached 50 km altitude with an apoapsis of 60km and is almost at Orbital velocity, 310 dv is needed to reach final orbit and even with a TWR of .25 there is just enough thrust to increase apoapsis faster than the rocket approaches it. Soon AP hits 80 and the now 1800 degree engines are allowed to cool for a brief 2 minutes while coasting towards it, raising periapsis requires a short burp of power and a mere 40 dV.
Total was just over 4020 dV which is quite high, however the low thrust engines require reaching high altitude and apoapsis as early as possible.

[RedKing]

I think the UN would like to have a word with you about your orbital WMD there.... 

[Eric Blank]

That's fission reactor fuel, for the space station.

[Leonon]

That's more than 10% of the IRL yearly global production of the stuff.

Why do you need that much uranium in space? What's that space station going to do?

[SOLDIER First]

Total Time Playing KSP: >48 Hours
Total Successful Munar Orbits (Not in Scenario Mode): 0
Total Career Mode Kerbin Orbits: 0

[MagmaMcFry]

Total Time Playing KSP: >48 Hours
Total Successful Munar Orbits (Not in Scenario Mode): 0
Total Career Mode Kerbin Orbits: 0

Looks like you need more stages.

[MarcAFK]

That's more than 10% of the IRL yearly global production of the stuff.

Why do you need that much uranium in space? What's that space station going to do?

You see Ivan, when you ranium in space, much respect you get from the west.

[Lightningfalcon]

I think the UN would like to have a word with you about your orbital WMD there.... 

*rocket starts tipping over* Well, time to start sounding the sirens. 

[RedKing]

I built a small go-kart out of a lander can, some modular girders, small landing gear and a pair of Spark engines. Fun little thing (and it lets me soak up all the science points for doing EVA/surface sample/temp/pressure/Mystery Goo all around the space center).

Mark II added an RCS tank and thruster block on top of the lander can, so I can back up. If I didn't mind going slow, I could probably propel the whole damn thing using nothing but RCS.

[miauw62]

If you're orbiting kerbin and want to get to the Mun, all you really have to do is make a node and pull prograde until it intersects with the Muns orbit and then move the node until you get an intercept. Then you want to just burn retrograde at the Muns apoapsis.

Also, don't overengineer. Lighter craft need less fuel to get to orbit.