Abstract: A midair collision avoidance system (MCAS) employs an existing design of Traffic Alert and Collision Avoidance System (TCAS) as a module and seamlessly integrates it with a customized tactical module which is capable of providing unique tactical avoidance guidance control and display. The tactical module handles all phases of a tactical mission, including formation flight (e.g., formation fall-in, arming formation flight, engaging formation flight following, and formation break-away), and an air-refueling sequence (e.g., rendezvous, linkup, re-fueling, and disengaging air-refueling). The tactical module divides the air space around the aircraft into advisory, caution, and warning zones and for each provides display, tone and voice alerts to facilitate pop-up avoidance guidance commands. Military aircraft can thus effectively avoid mid air and near mid air collision situations in all three different operation modes: air traffic control (ATC) management mode, tactical mode, and a mixed mode.