Flight Reliability
F9 4277 · Frontier Airlines
Washington → Las Vegas (IAD–LAS)
78
Usually Fine
WanderNerd Reliability Score
- 71%
- Arrive within 15 minutes
- 12 min
- Average arrival delay
- 0%
- Cancelled
- 7 min early
- Median arrival delay
Based on 94 historical flights. Data through May 2026.
What the data says
Friday is doing you no favors.
F9 4277 arrived on time 93% of the time on Thursdays and just 53% on Fridays. That gap is worth planning around.
Lagging the IAD–LAS route.
F9 4277 arrived on time 71% of the time, versus 85% across the IAD–LAS route.
The breakdown
- Mon60%(15 flights)
- Tue73%(11 flights)
- Wed80%(10 flights)
- Thu93%(15 flights)
- Fri53%(15 flights)
- Sat57%(14 flights)
- Sun86%(14 flights)
- 6–9 AM71%(83 flights)
- 9 AM–12 PM73%(11 flights)
73%
May
Jun 68% → May 73% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 68% | 25 |
| July 2025 | 74% | 31 |
| August 2025 | 73% | 26 |
| May 2026 | 73% | 11 |
- Departures on time
- 61%
- Diverted
- 0%
- Flights flown
- 94
- Months covered
- 5
Same route, other flights
Keep nerding
Based on 94 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.