Which departure time was most reliable for DEN to COS?
Among qualifying DEN-to-COS departure window results, Early morning had the highest on-time rate: 87.0% of 453 flights. Evening was lowest at 65.0% across 1,392 flights.
| Departure window | Flights | On time | 30+ min | Cancelled |
|---|---|---|---|---|
| Early morning | 453 | 87.0% | 8.8% | 0.2% |
| Late morning | 981 | 81.4% | 9.7% | 1.6% |
| Afternoon | 1,447 | 76.5% | 14.7% | 1.9% |
| Evening | 1,392 | 65.0% | 23.0% | 1.4% |
| Night | 766 | 72.5% | 18.8% | 1.2% |
Which weekday was most reliable for DEN to COS?
Among qualifying DEN-to-COS weekday results, Wednesday had the highest on-time rate: 78.7% of 703 flights. Friday was lowest at 69.5% across 728 flights.
| Day | Flights | On time | 30+ min | Cancelled |
|---|---|---|---|---|
| Monday | 721 | 75.9% | 14.1% | 0.7% |
| Tuesday | 700 | 76.1% | 15.0% | 1.3% |
| Wednesday | 703 | 78.7% | 13.2% | 1.0% |
| Thursday | 720 | 72.9% | 17.1% | 1.8% |
| Friday | 728 | 69.5% | 19.4% | 2.6% |
| Saturday | 715 | 75.2% | 16.4% | 0.8% |
| Sunday | 752 | 74.2% | 17.3% | 1.9% |
Which airline was most reliable for DEN to COS?
Among qualifying DEN-to-COS airline results, United Airlines had the highest on-time rate: 76.4% of 614 flights. Southwest Airlines was lowest at 72.6% across 1,142 flights.
| Airline | Flights | On time | 30+ min | Cancelled |
|---|---|---|---|---|
| SkyWest Airlines | 3,283 | 75.0% | 16.0% | 1.9% |
| Southwest Airlines | 1,142 | 72.6% | 15.9% | 0.4% |
| United Airlines | 614 | 76.4% | 16.8% | 1.0% |
Which month was most reliable for DEN to COS?
Among qualifying DEN-to-COS month results, February 2026 had the highest on-time rate: 82.7% of 346 flights. July 2025 was lowest at 56.0% across 466 flights.
| Month | Flights | On time | 30+ min | Cancelled |
|---|---|---|---|---|
| July 2025 | 466 | 56.0% | 29.2% | 3.6% |
| August 2025 | 466 | 63.3% | 26.4% | 1.1% |
| September 2025 | 443 | 79.0% | 11.7% | 0.0% |
| October 2025 | 450 | 81.6% | 10.7% | 0.0% |
| November 2025 | 426 | 79.6% | 7.0% | 8.0% |
| December 2025 | 441 | 75.1% | 16.8% | 1.1% |
| January 2026 | 387 | 78.0% | 15.0% | 1.3% |
| February 2026 | 346 | 82.7% | 10.7% | 0.3% |
| March 2026 | 388 | 79.4% | 14.2% | 1.0% |
| April 2026 | 362 | 81.2% | 12.4% | 0.0% |
| May 2026 | 428 | 76.6% | 15.0% | 0.2% |
| June 2026 | 436 | 68.6% | 20.4% | 0.2% |
What drove DEN to COS delay minutes?
Late aircraft was the largest recorded DEN-to-COS delay category, accounting for 40.1% of 80,682 BTS-attributed delay minutes during July 2025–June 2026.
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