Looking at this shaft idea, it gave me an idea. Utilizing the Earth's natural magnetic and gravitational forces to our advantage, why not utilize the terminal velocity, have a massive enough vehicle going down the pipeline (for a higher TV), and line the pipeline with electromagnets throughout. Turn the planet into a gigantic railgun firing ships into distant parts of space. Hubble may have to be used as a crosshair however. Then again, we can always make use of the Himalayas and either use the range or Mt. Everest itself as a natural muzzle for takeoff.
The time it would take to travel through Hell, spend a split second in purgatory (IE- The Earth's crust), and fly off into the heavens should be cut dramatically; and if we can construct a massive enough space craft that can house an entire civilization within, and launch that sucker; overpopulation and exo-system space travel will both become realities. And in case aliens decide to visit and undo the megaproject, our planet is now a death star, except made of rock and is a massive railgun (or has many of them if we're not cutting through the entire planet, but along the sides; shallow-shafts).
I think a better example to base a proper railgun-shuttle system off of is probably the LHC. Have a long enough pipeline, keep the turn angle subtle, but able to loop around (at least enough to still fall vertically, but still not hit the core itself, while exiting vertically).
I can't believe it, but my head is churning out a blueprint of how it can be done. But it may have to wait until tomorrow when I'm more awake to draw it. But one idea that immediately springs to mind is a tectonic stabilizer. It has to be resistant to it, otherwise either the trajectories can be severely messed up, or the entire system could crumble, and the devil would be pissed.
ADDENDUM:
Got another idea, we can use the moon as a secondary crosshair and slingshot our space bullet-trains wherever we want just by subtly altering the course of the shot by aiming the muzzle at the edge of the moon or we can fire straight across sans lunar influence.
BTW, I have an MSPaint mockup made.
Gimme a sec to upload it. Uploaded.