RTCA DO-239

Description / Abstract: This document presents requirements for the aircraft equipment associated with Traffic Information Service Data Link (TISDL) communications. The TIS data link function is intended to improve the safety and efficiency of “see and avoid” flight by providing pilots with automatic display of nearby traffic and warnings of any potentially threatening conditions. The source of TIS information is the file of aircraft tracks maintained by the ground Mode S sensor providing coverage for a region of airspace. TIS generates alerts for any traffic aircraft in Mode S coverage that carry a transponder (ATCRBS or Mode S). TIS provides traffic advisories similar to those of TCAS-1, but does not provide resolution advisories. Section 1 provides information and assumptions needed to understand the rationale for equipment characteristics and requirements. Section 2 contains the minimum performance standards for the equipment. Section 3 describes the performance required of the installed equipment and Section 4 describes the operational performance characteristics for equipment installations.