Week 2026 / 36 · 2026-08-31 – 2026-09-06
Week 36 (31 August–6 September 2026): Integrity-drop measurements (consistent with GNSS degradation)
Indicative · based on ADS-B integrity (NIC) data
Affected aircraft-hour share
%3.6
▲ 0 pp vs previous week
Affected aircraft-hours
6,709
/ 186,526 aircraft-hours
Events
260
260 medium/high sufficiency
Position anomalies
96
high/medium-sufficiency events
Day by day
Each day's affected aircraft-hour share (%). Peak day in dark colour.
- 3.1Mon
- 3.6Tue
- 3.8Wed
- 3.2Thu
- 3.8Fri
- 3.7Sat
- 3.9Sun
Last 12 weeks
Weekly share; this report is the highlighted point. Weeks without data are left blank.
%3.1%4.1
Highest FIRs
Regions with enough sample during the week, by affected aircraft share.
- Ankara%10.8
- Damascus%8.3
- Bucharest%5.7
- Istanbul%4.4
- Sofia%4.3
- Amman%2.9
- Nicosia%2.7
- Cairo%2.4
Cell map of the peak day · 2026-09-06
Each polygon is an H3 cell; “no data” does not mean calm.
- Insufficient data
- Low
- Medium
- High
Largest event of the week
Istanbul
342
2026-09-05, 00–22 UTC, 23 hours in total. The number of unique affected aircraft is shown above.
Position anomalies (spoofing) · day by day
High- and medium-sufficiency events (rule-based, focus region only); high in dark colour.
- 13Mon
- 8Tue
- 14Wed
- 14Thu
- 11Fri
- 8Sat
- 28Sun
Findings this week
- In the regional scope (Türkiye and neighbours), 3.60% (6,709) of 186,526 aircraft-hours over seven days showed degraded navigation integrity; the daily rate ranged from 3.09% to 3.93%. The peak day was 6 September (3.93%), followed by 4 September (3.82%). These data do not identify the cause of any rise or fall.
- Share of aircraft affected by region (weekly, FIRs with sufficient observation volume): Ankara 10.8%, Damascus 8.3%, Bucharest 5.7%, Istanbul 4.4%, Sofia 4.3%.
- The integrity-drop event affecting the most aircraft this week was on 5 September in the Istanbul FIR: 342 unique aircraft, 23 hours (00–22 UTC), 49 cells (event = connected medium/high-level cell-hours). All days of the week were produced with the same algorithm version (1.5.0), so the events are comparable with one another.
- Position anomalies (spoofing, rule-based, focus region): 96 high/medium-confidence events this week (91 high, 5 medium); busiest day 6 September (28). There are also 15 low-confidence events and 506 jumps overlapping with low integrity; jumps coinciding with integrity loss are not counted in this headline figure; the cause is not stated. Indicator only: it states no cause.
Data period, version and scope
This report was published on 15 October 2026 and rests on the published data of that day: regional scope (Türkiye and neighbours), algorithm 1.5.0 (a single affected-aircraft definition is used: a notable share of reports showing low integrity; faulty-transmitter filter applied). This report was prepared retrospectively on 15 October 2026, after the week ended: the figures show the current reprocessed series, not necessarily what would have been published at the time. Earlier weekly reports may have been prepared with a different scope or algorithm version; reports must not be compared directly. The data come from a single source (adsb.lol); areas without receivers are invisible and “no data” does not mean “calm”. It is an indicator only: it states no cause and makes no definitive detection claim.
This report is based on observed ADS-B data and is not an operational navigation source. See the methodology page for the general framework.