The control room at Inmarsat’s headquarters in London. The loss of Air France Flight 447 prompted Inmarsat to embed more time information in its satellite communications, which allowed it to calculate the route of the missing Malaysia Airlines jet.

Missing Malaysia Airlines Jet Shines Spotlight on Tracking Technology

Satellite data have provided most of the clues in the search for the Boeing 777 that went missing in March, but such data sets have limits.

nytimes.com