a***s 发帖数: 206 | 2 Until just a few years ago, the satellite communication system used by
jetliners did not include data on an aircraft’s location, speed or altitude
in the pings, the electronic equivalent of handshakes used to establish
initial contact.
For instance, before Air France Flight 447 crashed into the Atlantic Ocean
in 2009, the jet sent some diagnostic data indicating problems with various
onboard systems, including the autopilot’s deactivation. But notably the
plane’s position wasn’t transmitted with that data.
Partly as a result it took nearly two years to locate the plane’s “black
boxes” and the majority of the wreckage. In the case of the missing
Malaysian jetliner, precise locations were provided. However, it is unclear
why the transmission ceased and where the plane may have ended up after the
final ping. |