>> another obstacle for rescue workers and aid in the area. thank you very much. jon: russian investigators pulling apart the wreckage of a plane after it crashed yesterday, killing all 50 people on board. the airlines flight on the way from moscow to kazahn. the black boxes have been recovered. now safety experts are trying to determine if the 23-year-old plane, yesterday's weather or possibly pilot error are the reasons for the crash. peter is the former managing director of the national transportation safety board. peter, until they get those black boxes and get the information on them deciphered, they'll not know a great deal about what happened there, are they? >> no. they understand that the pilot did a missed approach and was saying he was in an unstable condition coming around for a second landing but you won't know until you see the results