AI.II.B.R4FAA-S-ACS-25 · Nov 2023Risk management
Collision reaction time.
Collision reaction time.
Bottom line
It takes 12.5 seconds for a pilot to identify, react, and avoid a midair collision. High closure rates from the performance capabilities of many aircraft limit the time available for detection, decision, and evasive action. If another aircraft appears to have no relative motion, it is likely to be on a collision course.
FAA references
- AC 90-48, paras. 8.1.4, 8.1.6, 8.1.7, 8.1.8 — AC No: 90-48E
- AFH ch. 1 (pp. 1-10–1-11) — FAA-H-8083-3C
- AFH ch. 1 (p. 1-11) — FAA-H-8083-3C
- AIM 4-4-15 (Use of Visual Clearing Procedures and Scanning Techniques) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
- AC 90-48 ch. 4 — AC No: 90-48E
- AIM 8-1-8 (Judgment Aspects of Collision Avoidance) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
Build understanding you can use
Unlock the full lesson and continue studying this element.
- Full teaching sections: Hazard; How it shows up; Decision rules; Mitigations; The hazard
- Check your understanding with answers you can reveal