So, think about this for a moment. We live in a day and age where GPS (and other radio triangulation methods) can track your smartphone to within a few meters, almost anywhere on Earth. With dedicated, land-based tracking networks, vehicles and devices can be tracked to within a few centimeters. Even in the absence of GPS or radio tracking, inertial guidance (dead reckoning) has been accurate enough since the ’60s to accurately land a nuclear ICBM on the other side of the planet, or put the Apollo mission into space.

And then there’s connectivity. On land, there are networks (both commercial and governmental) that provide data connectivity almost everywhere. Over water is definitely harder, but satellites do provide pretty good coverage — and yes, that particular region of Asia is very well covered by communications satellites. Finally, even if an aircraft is out of satellite/radio coverage, there is absolutely nothing preventing the airplane from transmitting a really juicy low-frequency radio signal that could be picked up thousands of miles away. This is how they communicate with air traffic control, after all.

Why, then, does a plane like the MH370 keep all of its secrets locked up in a black box? Why don’t planes constantly transmit all of their black box data, so that we know their exact location, bearing, altitude, and other important factors, at all times? The short answer is, there’s no good reason. The long answer is, as you’d expect, a bit more complex.

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Perhaps, much like how your smartphone waits for a WiFi connection before downloading or uploading large amounts of data, the plane could scale up how much data it sends: It could transmit basic flight data at all times via VHF, and then a full stream of data from the FDR when there’s a communications satellite overhead. Ultimately, even though FDRs might record more than 100 variables and diagnostics, we’re still only talking about a maximum bandwidth requirement of a few megabits; realistically, a few hundred kilobits per second would probably be more than enough.