TCAS alert prevention (TCAP)

TCAS alert prevention (TCAP)


Airborne Collision Avoidance System (ACAS) Alert Prevention (TCAP) functionality has been introduced by Airbus to prevent the generation of Resolution Advisory (RA) in 1000-foot level-off geometries. The functionality which is currently available for the Airbus wide body aircraft (and expected to become available on the A320 family of aircraft) uses a new altitude capture law for flight guidance computers, which decreases aircraft’s vertical rate towards the selected altitude, once a Traffic Advisory (TA) has been generated and the autopilot and/or flight director are engaged.

The TCAP functionality is complementary to the flight guidance computer’s conventional altitude capture function.

The TCAP functionality has been specified in the Minimum Aviation System Performance Specification (MASPS) for Flight Guidance System (FGS) coupled to ACAS published by European Organisation for Civil Aviation Equipment (EUROCAE) (ED-224).

Illustration of an encounter without and with TCAP functionality

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