AD 2021-05-17 Prompted By Conflict Between The TCAS Display Indications And Aural Alerts

The FAA is superseding Airworthiness Directive (AD) AD 2019-12-09 for certain Rockwell Collins, Inc. (Rockwell Collins) FDSA-6500 flight display system applications installed on airplanes. AD 2019-12-09 imposed operating limitations on the traffic collision avoidance system (TCAS). AD 2019-12-09 was prompted by conflict between the TCAS display indications and aural alerts that may occur during a resolution advisory (RA) scenario.

This AD retains the requirements of AD 2019-12-09 until a software upgrade is completed. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective April 29, 2021.

Supplementary Information: The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2019-12-09, Amendment 39-19664 (84 FR 32260, July 8, 2019), (AD 2019-12-09). AD 2019-12-09 applied to certain part-numbered Rockwell Collins FDSA-6500 flight display system applications that may be installed on, but not limited to, Bombardier Inc. Model CL-600-2B16 (604 variant) airplanes and Textron Aviation Inc. Models 525B, B200, B200C, B200CGT, B200GT, B300, B300C, and C90GTi airplanes. The NPRM published in the Federal Register on December 14, 2020 (85 FR 80686).

AD 2019-12-09 prohibited operation with the TCAS in TA/RA mode by requiring a revision to the Limitations section of the airplane flight manual (AFM) or AFM supplement (AFMS) and by fabricating and installing a placard on each aircraft primary flight display. AD 2019-12-09 resulted from a report that a conflict could occur between the TCAS primary cockpit display indications and the aural alerts during an RA scenario. The FAA issued AD 2019-12-09 as an interim action to address the immediate urgency to prevent the pilot from over-correcting or under-correcting for aircraft separation, which may result in a mid-air collision.

In the NPRM, the FAA proposed to retain the actions of AD 2019-12-09 and install updated software on the flight data system applications within 12 months. Once the software is upgraded, the FAA proposed to allow removal of the limitations and placard. Because the requirements proposed in the NPRM had a longer compliance time, the FAA provided the public an opportunity to comment. The FAA is issuing this AD to address the unsafe condition on these products.

FMI: www.regulations.gov