CNN New Day March 24, 2015 11:22:00
You know they most likely had a mechanical something was wrong with the plane. as soon as they released the distress call if they got anything off other than mayday or asked for emergency landing clearance, they would have had to ask to change their flight leveles if they were levels if they were descending intentionally. air traffic control could clear the route for them. usually you say what it is you say you lost the power in your engines or you've got a lost the control or you can't get the flight service working, et cetera. but it sounds to me since they were able to declare an emergency,...
Source: archive.org