The disappearance of Malaysian Airlines Flight 370 (MH 370) carries many interesting naval and defense lessons. The first and most important is that the widely held belief that nearly anything on the surface of the Earth is more or less visible at all times, thanks to satellites and other sensors, is an illusion. Most satellites provide fleeting glimpses of the Earth. The only ones that stare continuously at the surface, from geostationary orbits, are so far away that their sensors are incapable of tracking most relatively small moving objects.
Many years ago the U.S. Navy considered building a constellation of radar satellites specifically to detect and track Soviet bombers that might attack its carriers. Because satellites low enough to use radars to detect and track aircraft do not hang over particular spots on the planet, the project required enough satellites so that at least one was always in place over the area of interest (mainly the North Atlantic and Norwegian Sea). It was soon obvious that the constellation was unaffordable. A lot has happened in technology since the 1980s, but the physics of satellite motion has not changed. Nor has radar physics. It would still take an unaffordable satellite constellation to maintain surveillance of much of the world’s airspace.