This is awesome. Really glad KSP continues to bring everyone along (now in 1.x edition) and didn't fizzle out while still in Early Access/beta. Loving the GBEast videos and community content like this.
@rethla said:
Launching east is generally a good idea if you want a quick, easy and efficient orbit but dont care what type of orbit it is. If you wanna do a rendezvous you should try to launch in the direction of the orbit you are trying to match. Launching just before the target will pass over your head is also a good idea. If you do those two things you will only have some small adjustments to do once in space.
Just an extra note for anyone who is only just starting out, playing at home reading through threads like this (and just wants to orbit, rather than match an existing orbit to hook up with something already in space).
Think of orbit as (for Kerbin low orbit, out of atmosphere so stable but not much more - the higher the stable orbit the slower you go) falling sideways at 2200 metres per second. When moving in a straight line parallel with the ground below you (which is curved to either side because sphere) you are clearly going to be moving away from the ground. But that stickler gravity means that you're also falling towards the ground. So going 2.2 km/s sideways is that happy balance where gravity pulls you down to exactly balance what would otherwise you going flying off into space due to the curvature of the planet. Result: stable orbit. But fundamentally you only really care about getting 70-90km above Kerbin to get out of the air resistance that will cause you to come crashing down. The final plan for vertical velocity is 0 m/s, it's all going to be about horizontal velocity. The important part is you need to be going sideways really quickly.
As Kerbin is a spinning globe then you are not starting off from zero horizontal velocity. As you launch, staying entirely "stationary" above the launch site means you're actually already going at 175 metres a second sideways in the direction of East. Because Kerbin rotates. So, as we need to get to 2.2 km/s horizontally, we're already 8% of the way there if we increase our velocity East. We only need a delta-V (change in velocity) of ~2 km/s to get to where we want to go for an orbit.
Heading West means you need a delta-V of ~2.4 km/s to set up an orbit going the other way, because the first 175 m/s of delta-V is simply undoing the rotation you had when sat on the ground from the spinning globe you started on. So you need more thrust (and so more fuel) to get into orbit when launching Westerly. Hopefully someone reading this has just gone, "Oh, that suddenly makes perfect sense!"
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