Known Fact for Flat Earth - Trolls state their opinion as unquestionable fact 

The idea that there could be no system for location other than GPS is ridiculous. Look into things such as Loran. There is also the ability to radio triangulate across large distances. We have radio that can go across the world, and yet there's nothing that can give us location other than a satellite in space? I really disagree with this. You should also look at the reports of GPS not working at high altitude, which is very bizarre as they should work better higher up.

William Brower - Never say there is not ground based localisation system...there is. Just say than GPS itself is not ground based as it work on location none of those other ground based system possible work. And no, we cannot quite send radio signal across the globe...not direct one at least. We can send direct signal (line of sight) and ground signal....and then we can send ionospheric refraction. But here the deal...there is a gaps between them. There is a zone called a skip zone where you cannot reach with with ground/direct signal, but you are still too close for a refraction as well (as they require a certain angle minimal angle) GPS however, work perfectly fine in those zone where you cannot get contact to ground. And also, GPS signal work just fine at hi altitude. The real problem is not the signal. Real problem is the triangulation method (yep, that a math problem). Algorithm used in devise designed to be used at a specific altitude (around ground level) lose accuracy with altitude as this is a factor greatly affecting the triangulation calculation. There is however specific GPS equipment designed for hi altitude than will often incorporate a separate devise to determine altitude and ensure the devise get the tool it require to properly triangulate yourself (where your average Garmin gps don't...so using only satellite data and algorithm designer for ground purpose...he get confuse if you try to send him 100 000 feet in the air.

GPS does not work flawlessly in the middle of the ocean. That's a pretty hilarious claim, that has been proven to be false time and time again.