Several crew members were convinced from the start that it was a hostile military plane, and from that point on they filtered all the information coming in. The crew had rehearsed the a training scenario many times on what to do when there is a hostile military plane in their air space. They ignored evidence that it was, in fact, a commercial plane, paid attention only to the information that led them to think it was a hostile military craft, and then proceeded to carry out the training scenario. All leading them to an incorrect resolution.