Re-entry predictions of space debris for collision avoidance with air traffic

The need for a safe and efficient integration of space vehicle operations into air traffic system to minimize the risk of impacts of spacecraft and aircraft and to sustain a steady air traffic is evident. This work provides a strategy toward more efficient management of uncontrolled re-entries by combining uncertainty propagation analysis with the FAA's ConOps in the framework of the FAA's Next Generation Air Transportation System (NextGen). The paper considers the scenario where a spacecraft re-entry is completely uncontrolled. During such re-entry, predictions are very difficult and are affected by various sources of uncertainty. Then the resulting position distribution throughout airspace boundaries is analysed and the impact on air traffic is estimated by defining protected airspace areas. The impact of the size of the protected area on the air traffic control is analysed and strategies for re-routing of air traffic are proposed. To verify the proposed results, the re-entry of the core stage of the CZ-5B R/B launcher is simulated.