Hello everyone.

[Rhombolicious]

Hello. I started playing this game 2 days ago, and so for I'm really enjoying it. So I just wanted to say hello. I managed to get my first craft into orbit yesterday, but with no way for it to return home. Multiple failed rescue missions later, I'm having to abandon that save, but I loved every minute of it!

I'm also posting here looking for advice. I've been looking for guide, and all I can find is people running through different crafts to make. Can anyone recommend a good guide that covers the maths involved in determining the speed, etc of a craft. When I use boosters on a craft, it either goes too fast to turn, or too slow to break the atmosphere, and I want to find the balance without having to go through trial and error.

[Ty Tan Tu]

Greetings fellow newbie. The Wiki has a lot of good stuff.

http://wiki.kerbalspaceprogram.com/wiki/Main_Page

 

[Pecan]

Getting into orbit on your first day is good progress, well done.

There are two principle equations that govern rocket performance, giving the TWR and dV respectively:

TWR: Thrust to Weight Ratio - simply the total thrust of your engine(s) divided by the mass of your rocket.
Engine thrust is given when you mouse-over an engine in the VAB/SPH.  The total mass of the rocket is given in the 'engineer report' at the bottom of the screen (spanner icon).
If the TWR is <1 then your engines don't even have enough power to lift the rocket of the pad and you aren't going to space today.
At TWR = 1 you have enough thrust to hover, or maintain any ascent velocity you have, but can't accelerate away.
TWR 1.2 - 1.5 is good for a Kerbin launch.  The thing is as you burn fuel the rocket gets lighter so the TWR rises and a 1.2 launch TWR could end up at 3 or 4 by the time you get to space.  Unless you're staging engines and tanks ... in which case you need to work it out separately for each stage.

dV: Delta V - potential change (delta) in velocity (V), given by Tsiolkovsky's rocket equation (link to wikipedia, but simplified below)
dV = (Isp * G) * LN(Mass Wet / Mass Dry).  Broadly; you can do more stuff with more efficient engines and more fuel (makes sense ^^)
Isp is the 'fuel efficiency' of the engine, also given when you mouse-over an engine in the VAB/SPH
G is 9.81 m/s - a constant just used to convert the units to a speed.
LN is the 'natural logarithm' function in almost every spreadsheet and most calculators.  It means there are diminishing returns when you add more fuel, because you need to burn more fuel to lift the extra mass of the new fuel ... (see: tyranny of the rocket equation)
Mass Wet is the 'fuelled' mass of the rocket, as shown in the engineer report in the VAB/SPH.
Mass Dry is. consequently, the mass without fuel.  You can see it in the VAB/SPH by right-clicking (tweaking) each fuel-tank and removing the fuel.  Just remember to put it back in before you launch!

Do yourself a favour if you're not on a console - install a mod such as KER, MJ or VOID that calculates these for you on-the-fly.  They save an awful lot of work.

For Kerbin launch to orbit:  You need around 3,500m/s dV (3.5km/s) and a TWR >= 1.2 at launch.

NASA will tell you all about it in the real world (https://spaceflightsystems.grc.nasa.gov/education/rocket/guided.htm)

Edited July 30, 2016 by Pecan

[SorryDave]

Welcome! 

Trial and error is a big part of KSP, Mods like Kerbal Engineer Redux can help as you can add/subtract parts and see your delta-v and TWR immediately.

Although the learning curve might seem steep with trial and error, it won't be long before you've mastered orbit and begin the trip to the Mun.

The WIKI is useful to make sure you are not way off base, but trial and error will make you an expert quick enough.

Happy flying!