Flight Reliability
F9 4235 · Frontier Airlines
Denver → Salt Lake City (DEN–SLC)
100
Nerd Approved
WanderNerd Reliability Score
- 94%
- Arrive within 15 minutes
- 9 min early
- Average arrival delay
- 0%
- Cancelled
- 13 min early
- Median arrival delay
Based on 46 historical flights. Data through May 2026.
What the data says
The 9 AM–12 PM departure wins.
F9 4235 departing between 9 AM–12 PM arrived on time 100% of the time, versus 92% between 6–9 AM.
Mondays have been rough.
F9 4235 arrived on time 100% of the time on Fridays and just 82% on Mondays. That gap is worth planning around.
Well ahead of the DEN–SLC route.
F9 4235 arrived on time 94% of the time, versus 78% across the DEN–SLC route.
Well ahead of the Frontier Airlines network.
F9 4235 arrived on time 94% of the time, versus 73% across the Frontier Airlines network.
The breakdown
- Mon82%(11 flights)
- Tue—(0 flights)
- Wed—(0 flights)
- Thu—(9 flights)
- Fri100%(11 flights)
- Sat—(4 flights)
- Sun91%(11 flights)
- 6–9 AM92%(36 flights)
- 9 AM–12 PM100%(10 flights)
- Departures on time
- 96%
- Diverted
- 0%
- Flights flown
- 46
- Months covered
- 4
Same route, other flights
Keep nerding
Based on 46 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.