Flight Reliability
F9 3599 · Frontier Airlines
Atlanta → Denver (ATL–DEN)
63
A Little Dicey
WanderNerd Reliability Score
- 69%
- Arrive within 15 minutes
- 22 min
- Average arrival delay
- 1.8%
- Cancelled
- 1 min early
- Median arrival delay
Based on 169 historical flights. Data through May 2026.
What the data says
The late departure is the smart one here.
F9 3599 departing between 6–9 PM arrived on time 72% of the time, versus 51% between 9 PM–12 AM.
Saturdays have been rough.
F9 3599 arrived on time 83% of the time on Thursdays and just 44% on Saturdays. That gap is worth planning around.
Lagging the ATL–DEN route.
F9 3599 arrived on time 69% of the time, versus 77% across the ATL–DEN route.
A bit behind the Frontier Airlines network.
F9 3599 arrived on time 69% of the time, versus 73% across the Frontier Airlines network.
The breakdown
- Mon74%(27 flights)
- Tue57%(21 flights)
- Wed78%(18 flights)
- Thu83%(24 flights)
- Fri78%(27 flights)
- Sat44%(23 flights)
- Sun65%(26 flights)
- 9 AM–12 PM—(3 flights)
- 12–3 PM—(3 flights)
- 6–9 PM72%(125 flights)
- 9 PM–12 AM51%(35 flights)
77%
May
Nov 80% → May 77% on time
| Month | On-time percentage | Flights |
|---|---|---|
| November 2025 | 80% | 15 |
| December 2025 | 64% | 22 |
| January 2026 | 82% | 17 |
| February 2026 | 71% | 24 |
| March 2026 | 54% | 28 |
| April 2026 | 62% | 29 |
| May 2026 | 77% | 31 |
- Departures on time
- 58%
- Diverted
- 0%
- Flights flown
- 166
- Months covered
- 7
Same route, other flights
Keep nerding
Based on 169 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.