Flight Reliability
F9 4252 · Frontier Airlines
Salt Lake City → Denver (SLC–DEN)
- 78%
- Arrive within 15 minutes
- 0 min
- Average arrival delay
- 1.3%
- Cancelled
- 14 min early
- Median arrival delay
Based on 158 historical flights. Data through May 2026.
What the data says
The late departure is the smart one here.
F9 4252 departing between 9 PM–12 AM arrived on time 85% of the time, versus 70% between 6–9 PM.
Mondays have been rough.
F9 4252 arrived on time 86% of the time on Fridays and just 68% on Mondays. That gap is worth planning around.
A bit ahead of the Frontier Airlines network.
F9 4252 arrived on time 78% of the time, versus 73% across the Frontier Airlines network.
Trending in the right direction.
F9 4252 arrived on time 86% of the time over the last three months in the data, compared with 72% in the three months before that.
The breakdown
- Mon68%(28 flights)
- Tue—(5 flights)
- Wed—(5 flights)
- Thu77%(22 flights)
- Fri86%(28 flights)
- Sat76%(38 flights)
- Sun80%(30 flights)
- 3–6 PM—(3 flights)
- 6–9 PM70%(74 flights)
- 9 PM–12 AM85%(79 flights)
Jun 53% → May 91% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 53% | 15 |
| July 2025 | 67% | 12 |
| August 2025 | 72% | 18 |
| September 2025 | 76% | 21 |
| October 2025 | 79% | 19 |
| November 2025 | 88% | 24 |
| May 2026 | 91% | 23 |
- Departures on time
- 74%
- Diverted
- 0%
- Flights flown
- 156
- Months covered
- 12
Same route, other flights
Keep nerding
Based on 158 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.