authorities know the plane veered off course. but don't know why the boeing 777 with 239 people on board made a dramatic turn over the sea and don't know where the plane's journey ended. using satellite data search officials calculated it went down in the southern indian ocean and most recently have been combing an area of the ocean floor 1,000 miles of perth australia, 700 miles from where the debris was found. now investigators and scientists are calculatinging if pieces of the plane could have drifted that fwaur. >> experts stress other planes have crashed in the area and this piece could be from one of them. contacted by cnn, boeing would only say it is continuing to provide technical expertise to the search teams. brian todd, cnn, washington.