An aircraft collision avoidance system providing warning and avoidance manuevers for all fixed and moving obstructions that threaten the safe navigation of the host aircraft. The system is effective against threatening aircraft, runway maintenance vehicles and prominent geographic obstructions such as radio towers and mountain peaks. It is an economical combination of basic telemetry equipment (transmitter/receiver) and current personal computer components configured to broadcast its host location and intended movement while simultaneously receiving the same information from all nearby similarly equipped stations, either air or ground. Maximum effectiveness is attained when data is available from the Global Positioning System but alternative sources of navigational information including dead reckoning are provided for. Althrough intended primarily for aviation use, the same technology and concepts are valid for the safe transit of ships and railway equipment.