IR.II.B.K2aFAA-S-ACS-8C · Nov 2023Knowledge
a. Very high frequency (VHF) Omnidirectional Range (VOR), distance measuring equipment ...
Operation of the aircraft’s applicable navigation system(s), including: a. Very high frequency (VHF) Omnidirectional Range (VOR), distance measuring equipment (DME), instrument landing system (ILS), marker beacon receiver/indicators
Bottom line
The basic components of an ILS are the localizer, glide slope, and outer marker, and, when installed for use with Category II or Category III instrument approach procedures, an inner marker.
Key numbers
| Number | What it means |
|---|---|
| Less than 12,000 ft above facility elevation for ARINC 424 FOM 0 | DME/DME max height |
| At or above FL 240, within the 50 states and D.C., when VOR equipment is required | DME/RANAV at FL240 |
| More than 5 minutes predicted continuous loss | RAIM loss limit |
FAA references
- 14 CFR 91.175 (Takeoff and landing under IFR.) — eCFR current as of 2026-03-05
- AC 90-100 Appendix 1 — AC No: 90-100A
- 14 CFR 91.205 (Powered civil aircraft with standard U.S. airworthiness certificates: Instrument and equipment requirements.) — eCFR current as of 2026-03-05
- AC 90-105, para. 9.3.5 — AC No: 90-105A
- AC 90-107, para. 8e — AC No: 90-107
- AC 90-105 Appendix A — AC No: 90-105A
- AC 90-105, para. 8.4.4 — AC No: 90-105A
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