NEW : 15 bodies recovered ; identification could take weeks . NEW : Cold weather , lack of wreckage could prolong search as much as four days . Find out why » . NEW : Orientation of plane indicates that it fell flat on its belly , NTSB says . De - handling system was turned on at time of crash , FAA says .
NEW : 15 bodies recovered ; identification could take weeks . NEW : Cold weather , lack of wreckage could prolong search as much as four days . NEW : Orientation of plane indicates that it fell flat on its belly , NTSB says . De - handling system was turned on at time of crash , FAA says .