>> no. right now anything can be turned off because you can pull the fuses because they were worried about if a system catches on fire, you want to disable it. they are going to have to put the controls to that somewhere in the plane where it can't be turned off so we're never without -- something as simple as a transponder so no plane flying across the ocean can be turned off. since june 2009, 11 major planes have gone done over water and in 10 of the 11 crashes one black box could not be found. it does have to be -- it has to be a tradeoff of risk but it's important that it cannot be shut off. >> so many lessons from flight 370. thank you so much, mary, for joining us. really appreciate it. >> thank you. coming up, u.s. soldier is free at last. he was held by the taliban for five years. the u.s. traded for his release. was the cost too high? could it put other soldiers at risk? we'll speak to a retired major