Dan - they already have datalink and LF radio & radar tech on the ground and in the planes. It only works when in range and it can be manually circumvented. There are no towers in the middle of pacific. Secure, job specific arrayed satellites covering the sky or floating radar / data towers covering the oceans are the only way to "see" certain parts of Earth.

I just listened to a Government NSA / CIA / NASA data expert dude explain just how "dark" some of the earth really is. He did a much better job at explaining it than I am regurgitating it.

My guess is that the flight landed somewhere bad, all passengers were executed and the 777 is currently being retrofitted into an ICBM. Yeah - that...