man. >> reporter: the pilot's sister today urged people to stop blaming her brother, saying as things stand today with no tangible evidence none of you have the right to blame him for any wrongdoing. even adding that as an average student in school he would not have been able to mastermind such a plot. nobody knows why the plane lost contact, but some aviation experts theorize there could have been a massive electrical problem or a cockpit fire or loss of cabin pressure and oxygen, turning it into a ghost plane. >> why something hasn't shown up yet, that is the true mystery of it because of the fact that if it had crashed, in the way we think it did which is to run out of fuel and hit the water and break up into pieces there would be pieces somewhere. >> reporter: aviation analyst jeff wise carried on his own investigation into the missing plane, and has another theory. russian hijackers who took the plane to kazahkstan for reasons