How British satellite company Inmarsat tracked down MH370
Call me a conspiracy nut, but here's what I believe may have happened:It's almost a certainty that the US government has spy satellites video recording the entire planet at all times, at a level good enough to distinguish individual aircraft.  The US spy agencies probably knew where the plane was right away, but they can't just tell everybody or the jig is up.So they may have just contacted this satellite company, told them where the plane is, and came up with a technical explanation of how it was located.