assistant conductor on the amtrak train believes she heard the engineers oftt trains discussing the projectile in a radio transmission but she couldn t be sure of that recollection. al the ntsb says it is looking at video footage from both trains for any sign of a projectile and they ll bringing thin five. they have now interviewed the engineer of the train. he told him he was not tired before the crash. he wasn t sick wasn t on his cell phone. he told them he can t remember anything about the crash itself. he recalls ringing the train bell as he went through the north philadelphia station. that s not a normal station stop for him. but he s required by regulations to sound his bell. i may have said horn. he s required to sound his bell as he goes through past a