The named Resolution Advisory type for a single-threat encounter, derived
from the corrective/sense/rate/crossing/reversal flags per RTCA DO-185B
Table 2-16 (reproduced as Table 3 in the FAA's "Introduction to TCAS II
v7.1"). "Maintain Climb"/"Maintain Descend" and "Crossing Maintain
Climb"/"Crossing Maintain Descend" are not distinct wire values - they
are the same broadcast RA as climb/descend (or their crossing
variants), annunciated differently by the receiving aircraft's own TCAS
unit depending on whether it was already climbing/descending faster than
the initially-commanded rate.
The named Resolution Advisory type for a single-threat encounter, derived from the corrective/sense/rate/crossing/reversal flags per RTCA DO-185B Table 2-16 (reproduced as Table 3 in the FAA's "Introduction to TCAS II v7.1"). "Maintain Climb"/"Maintain Descend" and "Crossing Maintain Climb"/"Crossing Maintain Descend" are not distinct wire values - they are the same broadcast RA as
climb/descend(or their crossing variants), annunciated differently by the receiving aircraft's own TCAS unit depending on whether it was already climbing/descending faster than the initially-commanded rate.