Flight Reliability
UA 5109 · United Airlines
SLN → Denver (SLN–DEN)92% of its flights flew this route. The rest (DEN–BFF, DEN–WYS) are included in these numbers.
- 84%
- Arrive within 15 minutes
- 12 min
- Average arrival delay
- 0.3%
- Cancelled
- 8 min early
- Median arrival delay
Based on 395 historical flights. Data through May 2026.
What the data says
Mondays have been rough.
UA 5109 arrived on time 93% of the time on Fridays and just 69% on Mondays. That gap is worth planning around.
A bit ahead of the United Airlines network.
UA 5109 arrived on time 84% of the time, versus 79% across the United Airlines network.
It basically never cancels.
Out of 395 scheduled flights, only 0.3% were cancelled.
Trending in the right direction.
UA 5109 arrived on time 91% of the time over the last three months in the data, compared with 79% in the three months before that.
The breakdown
- Mon69%(58 flights)
- Tue85%(52 flights)
- Wed85%(52 flights)
- Thu87%(55 flights)
- Fri93%(57 flights)
- Sat80%(59 flights)
- Sun87%(60 flights)
- 6–9 AM83%(392 flights)
- 9 AM–12 PM—(1 flights)
Jun 91% → May 94% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 91% | 34 |
| July 2025 | 83% | 29 |
| August 2025 | 73% | 40 |
| September 2025 | 94% | 46 |
| October 2025 | 74% | 31 |
| November 2025 | 77% | 31 |
| December 2025 | 56% | 32 |
| January 2026 | 83% | 30 |
| February 2026 | 96% | 28 |
| March 2026 | 90% | 31 |
| April 2026 | 90% | 30 |
| May 2026 | 94% | 31 |
- Departures on time
- 84%
- Diverted
- 0.3%
- Flights flown
- 393
- Months covered
- 12
Same route, other flights
Keep nerding
Based on 395 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.