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[tryrar]

Why do you have an ion engine on the back of a liquid fuel tank?

.....wha??? I don't have ANY ion engines in this design....

[Chattox]

It would appear I'm being retarded. What is this at the back?

[Rose]

That's a docking port.

[jocan2003]

That's a docking port.

I think he meant the blue thingy. If i remember right its part of that RCS autopilot/docking mod thingy and that blue ring would be the control unit for the mod.

[Chattox]

That's a docking port.

I think he meant the blue thingy. If i remember right its part of that RCS autopilot/docking mod thingy and that blue ring would be the control unit for the mod.

That is indeed what I meant, thanks Out of interest, what mod is that? I'm sick of failing at docking xD

[miauw62]

That's most certainly not an ion engine tough. It doesn't even look like an engine.

[tryrar]

Hydrotech RCS autopilot, a GREAT mod for learning to dock and for docking maneuvers in general. And yes, that's part of the mod, it's a new part that has both a camera and target pre-installed, as well as some monopropellent!

[Nao]

@Nao
I am going out on a limb here, but i am pretty sure that adding more radial engines would make for at more efficient ascent, because only 20% of the fuel is going into gaining velocity, the rest is wasted on gravity drag.
If you post your craft, I'll try and fiddle around with it.

This is only a small test done with hyperedit:

Craft starting mass from mun 60,7t, TWR: 1,214 (less than 2m/s2 acceleration)
735m/s Dv spent for orbit (~12x1km so its around the same as 5x5km circular if i had payed attention to where i was going)
I almost had !!FUN!!.

I tried creating a other designs with sufficient Dv to reach orbit from Munnar surface that would carry the pod, orange tank and gray big tank (and some legs), but no other went below 61t.
For example 6x LV-N + 6x 1ton tank had 705m/s Dv, 3,17 mun TWR and weighted almost 70t
4x LV-909 + 4x 2ton tank + 2x 1ton tank had Dv of 664m/s (around 600-650 needed) and a mun TWR of 1,96 with launch mass of 62,75t.

The weight of engines in KSP IS a big deal, (especially since they are heavier than real life equivalents).
Also 1,2 TWR means 60deg attitude at launch, and after 1/5 of ascent time the attitude is around 45deg, so its rather 50% (cos60=0,5) fuel effieciency at launch and 70% at 45 deg.

[Anvilfolk]

Quick guide GO:
- Do the whole orbiting thing until you get to a few clicks away.
- Set the target vessel as target, your speed is now given relative to target vessel.
- Point towards the target vessel and burn some fuel
- Once you're going a decent speed (100-200m/s maybe?), aim your ship towards the retrograde indicator.
- Before you pass the target ship, burn retrograde until relative speed is close to 0.
- Return to the step in bold

You'll get progressively closer with each iteration. As you do, approach with less and less speed. Take your time. As you approach with less speed, try to keep your prograde indicator on the target indicator. As you get even closer, switch to RCS rather than main thrusters. This should make a lot easier to keep the indicators together.

As general tips for final docking, try to orient the docking port straight north or straight south. This doesn't change with orbit movement, so it tells you how you're supposed to approach the target ship. If it's pointing north, you should approach from the north pointing south. Also, go very very slow, keep changing camera views, etc. At first, try it with very, very little cargo on a compact ship. That makes it a lot easier, otherwise RCS will unbalance your ship, e.g. thrusting sideways also turns your ship.

I hope these help

[Skyrunner]

Actually, going at 100 m/s can wreck your orbit really easily. I think 20 m/s is more reasonable. O.o

I usually get a difference of around 20~30 m/s and watch the orbit map until I get closer, then retrograde, rinse, repeat.

[ank]

Nao, aren't you comparing NERVA engines to normal engines? apples and oranges...
Or am i just confused?

[Nao]

Nao, aren't you comparing NERVA engines to normal engines? apples and oranges...
Or am i just confused?

NERVAs work like any other engine. The higher ISP doesn't mean anything other than the fuel is burned more efficiency (higher exhaust velocity). Aside from orbital operations (where TWR required is very small and burn length big), there is plenty of situations where other engines outperform NERVAs.
For example the booster which has atmosphere ISP of only 225s is better than aerospike engine 390 ISP for Eve ascent first stage (and for next stages the LV-T30 performs equally to the aerospike despite lower ISPs, and gets better at high altitudes)
Or more common example having 3000+m/s Dv last stage with mk1 capsule on top, LV-909 is performs better than NERVA even thou it requires more fuel, has less ISP and thrust. It all comes down to numbers, and LV-N are *very* heavy for their thrust.

In this particular situation, NERVA engines are best because of very low TWR requirement and long enough burn, but LV-909 come close behind.

[ShoesandHats]

Holy shit I'm orbiting the sun in a very similar orbit path to Kerbin. That might not seems very impressive because it probably isn't, but this is the first time I've established an orbit on anything. I was originally trying to just orbit Kerbin but then my apoapsis got way too large and I got picked up by the gravity of the sun. I originally thought the rocket too damn huge to accomplish anything, but it (sort of) worked.

[Putnam]

When I want to get out of the Kerbin system, I slingshot off the mun. Saves on ridic amounts of delta-V, since you only need an apoapsis slightly past the mun to do it.

[jocan2003]

I just made an hybrid between a rocket and a spaceplane.... it use athmo engine, get to 13km then start flying like a plane with a steady 25 degreeish inclinaison, fly as fast as possiblt a,d 30 sec before engines goes dry dueto lack of intake air, it goes on a 80 degree then rocket engage. Im doing a hard mode fuel challenge where im only allowed to use liquid fuel if i mined it using kethane miner/converter combo.

Im currently building a space station and im trying to find the most efficient way to get something in orbit. Well i did it. takes me about 200 liquid fuel for my athmo engines and a small 500ish fuel/oxy combo to get in a 85km orbit. Sadly my game crashed before i completed the circularisation so its an approximate. Best launcher so far.