Safety Assessments of ADS-B and ASAS

Three Safety Assessments conducted at different levels assess various applications of ADS-B and ASAS. They support different purposes: developing surveillance requirements; evaluation of the technology and its applications as a complete entity for an investment decision; and comparing the safety contributions of potentially alternative systems. The Operational Safety Assessment methodology adopted by RTCA/EUROCAE provides the common framework for these studies. ASAS is a very appropriate candidate for applying this method. Some aspects of the systems and applications are relatively immature. Nevertheless, early safety assessments are extremely useful in guiding developers to assure robustness where it is needed. The RTCA work seeks to develop surveillance performance requirements. Its work is still in the early stages. The other two studies are Comparative Safety Assessments. Both of these were directed by the FAA. One of these studies 25 assorted applications that address various enhancements. The other compares the safety of Airborne Conflict Management to the Traffic Alert and Collision Avoidance System. This paper discusses the application of the safety method and presents the findings of these studies.