A system using automatic dependent surveillance-broadcast (ADS-B) data and traffic alert and collision avoidance system (TCAS) data for determining navigation solutions for a vehicle is provided. The system has a communal position system (CPS) with a CPS sensor located in the vehicle. The CPS sensor receives ADS-B data and TCAS data from each of one or more proximate vehicles. The system further has a computer system coupled to the CPS. The computer system is configured to perform the steps of: checking the ADS-B data and the TCAS data for data reasonableness; performing data synchronization of the ADS-B data and the TCAS data; and computing a CPS position and a position accuracy based on the ADS-B data and the TCAS data. The navigation solutions include an alternate navigation solution, an independent navigation solution, and a complementary navigation solution.