DL521
DL521 (Delta Air Lines) is a multi-stop service on 2 routes, busiest Los Angeles to Dallas-Fort Worth. Of 707 departures recorded from October 2024 to July 2026, 87.5% left on time, according to the US BTS.
- On-time departures87.5%of 707 flights
- Average delay5.9 min
- July 202649▲ 58.1%vs July 2025
- Cancelled1.4%
- Legs flown under this number2
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 | 31 | 31 | 0.0% |
| February | 28 | 37 | ▲ 32.1% |
| March | 31 | 49 | ▲ 58.1% |
| April | 30 | 37 | ▲ 23.3% |
| May | 31 | 31 | 0.0% |
| June | 30 | 27 | ▼ 10.0% |
| July | 31 | 49 | ▲ 58.1% |
| August | 31 | – | – |
| September | 30 | – | – |
| October | 31 | – | in progress |
| November | 30 | – | – |
| December | 31 | – | – |
| Year to date (Jan–Jul) | 212 | 261 | ▲ 23.1% |
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 | 86.7% | 86.7% | 0.0% |
| February | 75.0% | 83.8% | ▲ 11.7% |
| March | 86.7% | 91.5% | ▲ 5.6% |
| April | 83.3% | 89.2% | ▲ 7.0% |
| May | 80.7% | 93.3% | ▲ 15.7% |
| June | 80.0% | 81.5% | ▲ 1.9% |
| July | 80.7% | 95.9% | ▲ 18.9% |
| August | 86.7% | – | – |
| September | 90.0% | – | – |
| October | 96.8% | – | in progress |
| November | 85.2% | – | – |
| December | 90.3% | – | – |
| Year-to-date average (Jan–Jul) | 81.9% | 88.8% | ▲ 8.5% |
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 | 1 | 1 | 0.0% |
| February | 0 | 0 | – |
| March | 1 | 2 | ▲ 100.0% |
| April | 0 | 0 | – |
| May | 0 | 1 | – |
| June | 0 | 0 | – |
| July | 0 | 0 | – |
| August | 1 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 3 | – | – |
| December | 0 | – | – |
| Year to date (Jan–Jul) | 2 | 4 | ▲ 100.0% |
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 98.6% 697
- Cancelled 1.4% 10
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
2| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| LAX DFW Los Angeles International Airport – Dallas Fort Worth International Airport | 1,983 | 6.3 min | 87.3% | 646 |
| DFW LAX Dallas Fort Worth International Airport – Los Angeles International Airport | 1,983 | 2.3 min | 90.0% | 61 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 20 | 20 | 100.0% | 0 |
| November 2024 | 30 | 30 | 86.7% | 0 |
| December 2024 | 31 | 31 | 90.3% | 0 |
| January 2025 | 31 | 30 | 86.7% | 1 |
| February 2025 | 28 | 28 | 75.0% | 0 |
| March 2025 | 31 | 30 | 86.7% | 1 |
| April 2025 | 30 | 30 | 83.3% | 0 |
| May 2025 | 31 | 31 | 80.7% | 0 |
| June 2025 | 30 | 30 | 80.0% | 0 |
| July 2025 | 31 | 31 | 80.7% | 0 |
| August 2025 | 31 | 30 | 86.7% | 1 |
| September 2025 | 30 | 30 | 90.0% | 0 |
| October 2025 | 31 | 31 | 96.8% | 0 |
| November 2025 | 30 | 27 | 85.2% | 3 |
| December 2025 | 31 | 31 | 90.3% | 0 |
| January 2026 | 31 | 30 | 86.7% | 1 |
| February 2026 | 37 | 37 | 83.8% | 0 |
| March 2026 | 49 | 47 | 91.5% | 2 |
| April 2026 | 37 | 37 | 89.2% | 0 |
| May 2026 | 31 | 30 | 93.3% | 1 |
| June 2026 | 27 | 27 | 81.5% | 0 |
| July 2026 | 49 | 49 | 95.9% | 0 |