Nineteen
days after it disappeared en route from Kuala Lumpur to Beijing, there are
still few facts that point to what exactly happened to Flight MH370.
Based on
these, experts have three theories, though there may be more as clues emerge.
It is
known that the jet's communication and tracking systems - the transponder, and
the Aircraft Communications Addressing and Reporting System or ACARS - were
turned off deliberately.
