In early design phases, when we were familiarizing ourselves with the tasks and behavioral patterns of current Apache crewmen, one thing became obvious: these two crew members were spending a large portion—nearly a third by one informal estimate—of their time in intercrew communication and crew coordination behaviors. That is, they were talking to each other, explicitly, about what they were doing, what they intended to do, what they would like the other person to do, and so on. This was very unlike the operations of single-seat fighter aircraft where there was no one else to talk to.