IR.II.B.K2bFAA-S-ACS-8C · Nov 2023Knowledge
b. Area navigation (RNAV), global positioning system (GPS), Wide Area Augmentation Syst...
Operation of the aircraft’s applicable navigation system(s), including: b. Area navigation (RNAV), global positioning system (GPS), Wide Area Augmentation System (WAAS), flight management system (FMS), autopilot
Bottom line
A flight management system (FMS) is an integrated system of airborne sensor, receiver and computer with both navigation and aircraft performance databases. GPS is a U.S. satellite-based radio navigation system that provides a positioning service anywhere in the world. GNSS is a generic term for a worldwide position, velocity, and time determination system, and it includes GPS and satellite-based augmentation systems such as WAAS.
Key numbers
| Number | What it means |
|---|---|
| At or above FL 240, U.S.-registered civil aircraft in the 50 states and D.C. need approved DME or a suitable RNAV system if VOR navigation equipment is required | FL 240 DME/RNAV |
| Notify ATC immediately when the required DME or RNAV system fails at and above FL 240 | Failure action |
FAA references
- AC 90-105 Appendix J — AC No: 90-105A
- 14 CFR 91.205 (Powered civil aircraft with standard U.S. airworthiness certificates: Instrument and equipment requirements.) — eCFR current as of 2026-03-05
- AFH ch. 13 (p. 13-8) — FAA-H-8083-3C
- AC 90-100, para. 4m — AC No: 90-100A
- RMH ch. 3 (p. 3-6) — FAA-H-8083-2A
- 14 CFR 91.711 (Special rules for foreign civil aircraft.) — eCFR current as of 2026-03-05
- RMH ch. 7 (pp. 7-3–7-4) — FAA-H-8083-2A
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