Why not transmit this flight data off the plane so it’s accessible almost instantly? Airlines, after all, track each of their flights everywhere in the world and can advise crews on course adjustments, security alerts, quick weather changes, and a host of other situations. Passengers are routinely offered in-air Wi-Fi and live television these days. So why keep vital data trapped on the plane?
The answer is mostly about one issue: cost. Sending all the data from each flight in real time via satellite would be enormously expensive. A 2002 study by L-3 Aviation Recorders and a satellite provider found that a U.S. airline flying a global network would need to spend $300 million per year to transmit all its flight data, even assuming a 50 percent reduction in future satellite transmission costs.