Preliminary Integrity Assessment of the LDACS Navigation Function

Various trade studies and analyses have been conducted to evolve the LDACS-NAV concept to meet certain performance requirements so that an LDACS implementation can be used by civil aircraft for navigation purposes. This paper continues this series of analyses by focusing on integrity requirements. A general LDACS architecture complying with an expected LDACSNAV specification is assessed for its feasibility in meeting integrity requirements specified for position sources enabling ADSB Out messages. The assessment is intended to guide the design of LDACS-NAV as it progresses through the standards-making process by identifying high-level integrity failure modes using fault tree analysis.