If the power is turned off the Launch Loop will not immediately fall out of the sky. As the loop slows it will gradually fall. This is also why most pictures show it operating over the ocean. We have a lot of ocean at the equator.
A space elevator is not passive. It needs active dampening systems to avoid resonances that would tear it apart. The failure modes for a space elevator are also pretty terrifying. The lower the break the less harmful it is, but higher breaks will cause huge amounts of damage. Worst case scenario, the whole cable comes down. That is 75000 km. (Assuming the traditional double-spool deployment.) The Earth's circumference is only 40000 km. It will wrap around the earth twice! 'Blue Mars' has more about what such a disaster might look like.
The loop is not more well known because it was only invented in 1981 and requires non-intuitive physics to explain. Space elevators are "simpler" (if you ignore the active control problems) and have been around since 1895, though the modern design dates to 1959.
> If the power is turned off the Launch Loop will not immediately fall out of the sky. As the loop slows it will gradually fall.
That's for a loop constructed only of superconductors and magnets. If you use active electromagnets instead of the superconductors for saving money (or if your superconductors get too hot), the failure mode is way more harmful.
Anyway, I really don't know why the launch loop is so overlooked. Specifically, I don't know why nobody's trying to build an intercontinental bridge. It may be because of our anti-nuclear culture, and that those things only make any sense when coupled with nuclear power, but that's just speculation.
A space elevator is not passive. It needs active dampening systems to avoid resonances that would tear it apart. The failure modes for a space elevator are also pretty terrifying. The lower the break the less harmful it is, but higher breaks will cause huge amounts of damage. Worst case scenario, the whole cable comes down. That is 75000 km. (Assuming the traditional double-spool deployment.) The Earth's circumference is only 40000 km. It will wrap around the earth twice! 'Blue Mars' has more about what such a disaster might look like.
The loop is not more well known because it was only invented in 1981 and requires non-intuitive physics to explain. Space elevators are "simpler" (if you ignore the active control problems) and have been around since 1895, though the modern design dates to 1959.