let i letting people on the ground know that something was wrong. it's possible. typically you'd get malaysia flight 370 and they would repeat the frequency to the handle of controller, which would have been the vietnamese controller. but what happened after that is also telling. you have an airplane after a transponder and system was turned off became largely invisible to the air traffic controllers. then the plane makes a left turn. shortly thereafter and heads back in a southwesterly direction. what does it mean in short? >> it's a deal breaker why? because it gives greater evidence this plane was commandeered? >> exactly. and prior to this, there was uncertain. ty whether this plane had been commandeered, whether it had been hijacked, we had a lot of scenarios. but i think this make s it absolutely clear whoever said that on the air knew that the