UA519
UA519 (United Airlines) is a multi-stop service on 24 routes, busiest San Diego to Denver. Of 798 departures recorded from October 2024 to July 2026, 82.7% left on time, according to the US BTS.
- On-time departures82.7%of 798 flights
- Average delay9.4 min
- July 202641▼ 31.7%vs July 2025
- Cancelled0.8%
- Legs flown under this number24
Recorded departures by month
All legs under this number combined; see the leg table.
The most recent periods19 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 29 | 20 | ▼ 31.0% |
| February | 27 | 32 | ▲ 18.5% |
| March | 54 | 45 | ▼ 16.7% |
| April | 22 | 26 | ▲ 18.2% |
| May | 38 | 22 | ▼ 42.1% |
| June | 85 | 32 | ▼ 62.4% |
| July | 60 | 41 | ▼ 31.7% |
| August | 44 | – | – |
| September | 25 | – | – |
| October | 43 | – | in progress |
| November | 45 | – | – |
| December | 27 | – | – |
| Year to date (Jan–Jul) | 315 | 218 | ▼ 30.8% |
according to the US BTS · October 2024 → July 2026
On-time departures by month
On time = departure within 15 minutes of schedule. Non-cancelled flights with a recorded delay only.
The most recent periods19 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 89.7% | 100.0% | ▲ 11.5% |
| February | 88.9% | 93.8% | ▲ 5.5% |
| March | 75.9% | 86.1% | ▲ 13.3% |
| April | 81.8% | 100.0% | ▲ 22.2% |
| May | 73.0% | 95.5% | ▲ 30.8% |
| June | 75.3% | 68.8% | ▼ 8.7% |
| July | 67.8% | 75.6% | ▲ 11.5% |
| August | 72.7% | – | – |
| September | 75.0% | – | – |
| October | 100.0% | – | in progress |
| November | 93.3% | – | – |
| December | 92.6% | – | – |
| Year-to-date average (Jan–Jul) | 78.9% | 88.5% | ▲ 12.2% |
according to the US BTS · October 2024 → July 2026
Average departure delay by month
according to the US BTS · October 2024 → July 2026
Cancelled departures by month
The most recent periods19 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 0 | 1 | – |
| February | 0 | 0 | – |
| March | 0 | 2 | – |
| April | 0 | 0 | – |
| May | 1 | 0 | ▼ 100.0% |
| June | 0 | 0 | – |
| July | 1 | 0 | ▼ 100.0% |
| August | 0 | – | – |
| September | 1 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 2 | 3 | ▲ 50.0% |
according to the US BTS · October 2024 → July 2026
This is a historical record of departures already flown, not a forecast for your flight.
Several legs: the headline figure averages all of them. See the leg table.
Cancellation share
- Not cancelled 99.2% 792
- Cancelled 0.8% 6
Share of all recorded flights in the period, all legs. · Oct 12, 2024 → Jul 31, 2026
On time, leg by leg
Departures within 15 minutes of schedule; small figure = departures recorded.
Legs flown under this number
4| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| SAN DEN San Diego International Airport – Denver International Airport | 1,371 | 8.0 min | 82.5% | 335 |
| DEN MCO Denver International Airport – Orlando International Airport | 2,486 | 2.9 min | 84.4% | 188 |
| ORD MIA Chicago O'Hare International Airport – Miami International Airport | 1,930 | 21.8 min | 76.5% | 102 |
| BOS ORD Boston Logan International Airport – Chicago O'Hare International Airport | 1,391 | 5.0 min | 89.2% | 37 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 33 | 33 | 84.9% | 0 |
| November 2024 | 17 | 17 | 88.2% | 0 |
| December 2024 | 31 | 31 | 83.9% | 0 |
| January 2025 | 29 | 29 | 89.7% | 0 |
| February 2025 | 27 | 27 | 88.9% | 0 |
| March 2025 | 54 | 54 | 75.9% | 0 |
| April 2025 | 22 | 22 | 81.8% | 0 |
| May 2025 | 38 | 37 | 73.0% | 1 |
| June 2025 | 85 | 85 | 75.3% | 0 |
| July 2025 | 60 | 59 | 67.8% | 1 |
| August 2025 | 44 | 44 | 72.7% | 0 |
| September 2025 | 25 | 24 | 75.0% | 1 |
| October 2025 | 43 | 43 | 100.0% | 0 |
| November 2025 | 45 | 45 | 93.3% | 0 |
| December 2025 | 27 | 27 | 92.6% | 0 |
| January 2026 | 20 | 19 | 100.0% | 1 |
| February 2026 | 32 | 32 | 93.8% | 0 |
| March 2026 | 45 | 43 | 86.1% | 2 |
| April 2026 | 26 | 26 | 100.0% | 0 |
| May 2026 | 22 | 22 | 95.5% | 0 |
| June 2026 | 32 | 32 | 68.8% | 0 |
| July 2026 | 41 | 41 | 75.6% | 0 |