AA.I.E.K4FAA-S-ACS-11A · Nov 2023Knowledge
Flightpath warning systems (e.g., Traffic Alert and Collision Avoidance Systems (TCAS),...
Flightpath warning systems (e.g., Traffic Alert and Collision Avoidance Systems (TCAS), Terrain Awareness and Warning System (TAWS) and how to respond to a warning.
Bottom line
TCAS and TAWS are flightpath warning systems covered in navigation and flightpath warning system training. A warning alert is for a condition that requires immediate flightcrew awareness and immediate flightcrew response.
Key numbers
| Number | What it means |
|---|---|
| Turbine-powered Part 121 airplanes of more than 33,000 pounds maximum certificated takeoff weight | TCAS II weight |
| Turbine-powered airplanes manufactured on or before March 29, 2002 may not be operated after March 29, 2005 without approved TAWS | TAWS cutoff |
FAA references
- AC 61-138, para. 14.3.10.2 — AC No: 61-138A
- 14 CFR 25.1322 (Flightcrew alerting.) — eCFR current as of 2026-10-08
- 14 CFR 121.356 (Collision avoidance system.) — eCFR current as of 2026-10-01
- 14 CFR 121.354 (Terrain awareness and warning system.) — eCFR current as of 2026-10-01
- AC 120-90 Appendix 1 — AC No: 120-90
- AC 120-51 Appendix 3 — AC No: 120-51E
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