ARTCC NOTAMs (A1297/26, A0935/26) — GPS (WAAS/GBAS/ADS‑B) may be unavailable daily 20–23 Oct 2026 inside up to 330 NM radius centered at 303831N0862147W
Event summary
ARTCC NOTAMs (A1297/26 and A0935/26) reference GAFCFL GPS 26-11 testing and warn 'GPS (INCLUDING WAAS, GBAS, AND ADS-B) MAY NOT BE AVBL' during daily windows on 20–23 Oct 2026. The NOTAM texts specify an altitude‑dependent footprint up to a 330 NM radius centered at 303831N0862147W; affected operators should verify live NOTAMs and plan mitigations before operations.
CHRONOS Wire · October 20 · Alert 11
Publication details
- Published
- Updated
- Revision
- r1
- Source
- Notamify (extract of FAA/ARTCC NOTAM A1297/26)
Cliff Notes
- NOTAMs A1297/26 and A0935/26 (GAFCFL GPS 26-11) list planned GPS unavailability windows on 20–23 Oct 2026 with altitude‑dependent radii up to 330 NM centered at 303831N0862147W; check live NOTAMs before operations.
U.S. Impact
Current impact
Low
NOTAMs schedule short daily windows of planned GPS unavailability on 20–23 Oct 2026; operators relying on GNSS should check latest NOTAMs and plan alternates.
Potential impact
Elevated
Planned NOTAM windows affect Gulf/Florida ARTCC sectors with altitude‑dependent radii up to 330 NM; could degrade GPS‑dependent navigation, WAAS LPV approaches and ADS‑B surveillance during the listed windows and require procedural mitigations.
- Impact type
- Direct
- Confidence
- High
U.S. Impact is an analytical assessment of the estimated current and potential effects on the United States. It is not a probability forecast.
ELI5: Plain-English Explanation
FAA ARTCC NOTAMs warn planned GPS interference/testing (GAFCFL GPS 26-11) could make GPS, WAAS, GBAS and ADS‑B unreliable during announced daily windows on 20–23 Oct 2026 inside a large, altitude‑dependent radius centered at 303831N0862147W. Pilots and other GNSS‑reliant operators in the Gulf/Florida area should check live NOTAMs and plan mitigations for the listed windows.
Why Urgent Level 3
The NOTAMs schedule large-area planned GPS unavailability over upcoming days, which can materially affect flight planning and GNSS‑reliant maritime navigation; operators need time to verify and implement mitigations.
What Changed
New ARTCC NOTAMs (e.g., A1297/26 and A0935/26) publish GAFCFL GPS 26-11 testing windows and warn 'GPS (INCLUDING WAAS, GBAS, AND ADS-B) MAY NOT BE AVBL' within an altitude‑dependent footprint up to a 330 NM radius centered at 303831N0862147W for dates covering 20–23 Oct 2026.
What Is Genuinely New
ARTCC NOTAMs A1297/26 and A0935/26 (GAFCFL GPS 26-11) explicitly specify planned GPS unavailability windows on 20–23 Oct 2026 and an altitude‑dependent footprint (up to 330 NM radius centered at 303831N0862147W).
CHRONOS Bottom Line
ARTCC NOTAMs A1297/26 and A0935/26 announce planned GPS interference/testing (GAFCFL GPS 26-11) with daily windows on 20–23 Oct 2026 and an altitude‑dependent footprint up to 330 NM centered at 303831N0862147W; verify live NOTAMs before operations.
Uncertainties / Known Unknowns
Whether the tests proceed as published and the actual signal propagation/impact in specific localities; NOTAM variants show overlapping but not identical effective windows.
Detailed Analysis
NOTAMs A1297/26 (KZFW) and A0935/26 (KZTL) reference GAFCFL GPS 26-11 and warn 'GPS (INCLUDING WAAS, GBAS, AND ADS-B) MAY NOT BE AVBL' during specified daily windows between 20–23 Oct 2026. The notices list altitude‑dependent radii (330 NM at FL400–UNL down to 124 NM at 50 FT AGL) centered at 303831N0862147W. Operators should treat these as planning advisories and confirm the live NOTAM feed for updates or cancellations.
Sources / Evidence
- 01GPS, including WAAS, GBAS and ADS-B, may be unavailable in the affected area. - KZFW NOTAM | NotamifyNotamify (extract of FAA/ARTCC NOTAM A1297/26)
- 02GPS (GAFCFL GPS 26-11), including WAAS, GBAS, and ADS-B, may be unavailable in the affected area. - KZTL NOTAM | NotamifyNotamify (extract of FAA/ARTCC NOTAM A0935/26)
- 03FAASTeam notice: GPS Interference Testing Eglin AFB - GAFCFL advisoriesFAASTeam / faasafety.gov (GAFCFL flight advisory history)
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