AA.I.C.K5FAA-S-ACS-11A · Nov 2023Knowledge
Low-visibility operations (e.g., surface movement, category II and III approaches). (AT...
Low-visibility operations (e.g., surface movement, category II and III approaches). (ATP)(AMEL, AMES).
Bottom line
No person may operate a civil aircraft in a Category II or III operation unless the requirements of 14 CFR 91.189 are met. When the approach procedure provides for and requires a DA/DH, the authorized DA/DH is the highest of the DA/DH prescribed by the approach procedure, the DA/DH prescribed for the pilot in command, and the DA/DH for which the aircraft is equipped.
Key numbers
| Number | What it means |
|---|---|
| 100 feet above touchdown zone elevation, using approach lights as a reference, unless red terminating bars or red side row bars are also visible | Approach lights |
| 100 feet above touchdown zone elevation and below, one specified visual reference must be distinctly visible and identifiable | EFVS visual refs |
| From the authorized DA/DH to 100 feet above the touchdown zone elevation, an approach light system or both the runway threshold and the touchdown zone must be visible using an EFVS | EFVS segment |
FAA references
- 14 CFR 91.189 (Category II and III operations: General operating rules.) — eCFR current as of 2026-03-05
- 14 CFR 91.176 (Straight-in landing operations below DA/DH or MDA using an enhanced flight vision system (EFVS) under IFR.) — eCFR current as of 2026-03-05
- AC 61-138, para. 14.2.1.2 — AC No: 61-138A
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