In book two, Children of the Guardians, I wrote about how the Warrior Guild fled to the Saturn moon of Titan long ago. They revived an abandoned base that was in a "caretaker" status with only a few scientists left doing some experiments. But how would people survive on a planet that rained liquid methane? Wouldn't a single spark blow up the moon? Well, the lack of oxygen there would undoubtedly help prevent explosions, but if a colony were there, then oxygen would eventually find its way to the surface. So how would spaceships enter and exit the atmosphere without using an explosive propellant?
I had to think outside of the box, so here we go!
Friends, I give you Space Loops. These giant loops would propel a spaceship along a track much like a railgun uses magnetic pulses to accelerate a projectile. But why rely on that alone? I decided to add the planetary spin into the equation, and placed the Space Loops at the equator. The spacecraft would start at the top of a small loop being accelerated by gravity and the magnetic pulses on the way down the loop. As it began the journey up the loop, the magnetic pulses would maintain the same speed until it reached the top of the next loop. Each loop would increase in size until the craft could reach escape velocity.
What would be the advantages? The most obvious is that the rocket propellants we use today are highly explosive and dangerous. They are also very expensive. While the Space Loops would be expensive to construct initially, they would eventually pay for themselves because they could safely accomplish multiple launches. Using the natural energies of the planet (gravity, and rotational spin) would be another advantage. With the abundance of liquid methane on Titan to fuel their power plants, there would be a surplus of energy to operate these structures.
The less obvious advantage would be the launch process itself. The passengers would have considerably less stress on take off as the ship was slowly accelerated instead of a massive controlled explosion that we see today. This would also be considerably safer as well.