Flight Reliability
DL 2166 · Delta Air Lines
San Francisco → Salt Lake City (SFO–SLC)81% of its flights flew this route. The rest (LAX–BOS, CLT–MSP) are included in these numbers.
- 81%
- Arrive within 15 minutes
- 8 min
- Average arrival delay
- 0%
- Cancelled
- 9 min early
- Median arrival delay
Based on 168 historical flights. Data through May 2026.
What the data says
6–9 PM has a slight edge.
Departures between 6–9 PM arrived on time 82% of the time, against 78% between 3–6 PM.
Friday is doing you no favors.
DL 2166 arrived on time 92% of the time on Tuesdays and just 67% on Fridays. That gap is worth planning around.
It basically never cancels.
Out of 168 scheduled flights, only 0.0% were cancelled.
Slipping a little lately.
DL 2166 arrived on time 80% of the time over the last three months in the data, compared with 85% in the three months before that.
The breakdown
- Mon67%(27 flights)
- Tue92%(26 flights)
- Wed92%(26 flights)
- Thu82%(27 flights)
- Fri67%(27 flights)
- Sat—(6 flights)
- Sun86%(29 flights)
- 3–6 PM78%(32 flights)
- 6–9 PM82%(136 flights)
Jun 72% → May 80% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 72% | 25 |
| July 2025 | 83% | 23 |
| August 2025 | 75% | 20 |
| September 2025 | 94% | 17 |
| October 2025 | 87% | 23 |
| November 2025 | 83% | 18 |
| December 2025 | 77% | 17 |
| May 2026 | 80% | 25 |
- Departures on time
- 79%
- Diverted
- 0%
- Flights flown
- 168
- Months covered
- 8
Same route, other flights
Keep nerding
Based on 168 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.