DL509
DL509 (Delta Air Lines) is a multi-stop service on 10 routes, busiest Detroit to San Francisco. Of 477 departures recorded from October 2024 to July 2026, 67.3% left on time, according to the US BTS.
- On-time departures67.3%of 477 flights
- Average delay27.4 min
- July 202618▼ 18.2%vs July 2025
- Cancelled0.6%
- Legs flown under this number10
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 | 8 | 30 | ▲ 275.0% |
| February | 8 | 28 | ▲ 250.0% |
| March | 16 | 28 | ▲ 75.0% |
| April | 18 | 28 | ▲ 55.6% |
| May | 25 | 26 | ▲ 4.0% |
| June | 27 | 19 | ▼ 29.6% |
| July | 22 | 18 | ▼ 18.2% |
| August | 25 | – | – |
| September | 26 | – | – |
| October | 26 | – | in progress |
| November | 24 | – | – |
| December | 26 | – | – |
| Year to date (Jan–Jul) | 124 | 177 | ▲ 42.7% |
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 | 62.5% | 50.0% | ▼ 20.0% |
| February | 37.5% | 82.1% | ▲ 119.0% |
| March | 66.7% | 57.1% | ▼ 14.3% |
| April | 77.8% | 50.0% | ▼ 35.7% |
| May | 76.0% | 69.2% | ▼ 8.9% |
| June | 74.1% | 52.6% | ▼ 28.9% |
| July | 68.2% | 38.9% | ▼ 43.0% |
| August | 76.0% | – | – |
| September | 84.6% | – | – |
| October | 92.3% | – | in progress |
| November | 78.3% | – | – |
| December | 68.0% | – | – |
| Year-to-date average (Jan–Jul) | 66.1% | 57.1% | ▼ 13.5% |
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 | 0 | 0 | – |
| February | 0 | 0 | – |
| March | 1 | 0 | ▼ 100.0% |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | 0 | 0 | – |
| July | 0 | 0 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 1 | – | – |
| December | 1 | – | – |
| Year to date (Jan–Jul) | 1 | 0 | ▼ 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 99.4% 474
- Cancelled 0.6% 3
Share of all recorded flights in the period, all legs. · Oct 13, 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 |
|---|---|---|---|---|
| DTW SFO Detroit Metropolitan Wayne County Airport – San Francisco International Airport | 3,337 | 27.7 min | 61.4% | 295 |
| SNA SLC John Wayne Orange County International Airport – Salt Lake City International Airport | 947 | 27.2 min | 85.3% | 110 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 13 | 13 | 69.2% | 0 |
| November 2024 | 16 | 16 | 75.0% | 0 |
| December 2024 | 20 | 20 | 45.0% | 0 |
| January 2025 | 8 | 8 | 62.5% | 0 |
| February 2025 | 8 | 8 | 37.5% | 0 |
| March 2025 | 16 | 15 | 66.7% | 1 |
| April 2025 | 18 | 18 | 77.8% | 0 |
| May 2025 | 25 | 25 | 76.0% | 0 |
| June 2025 | 27 | 27 | 74.1% | 0 |
| July 2025 | 22 | 22 | 68.2% | 0 |
| August 2025 | 25 | 25 | 76.0% | 0 |
| September 2025 | 26 | 26 | 84.6% | 0 |
| October 2025 | 26 | 26 | 92.3% | 0 |
| November 2025 | 24 | 23 | 78.3% | 1 |
| December 2025 | 26 | 25 | 68.0% | 1 |
| January 2026 | 30 | 30 | 50.0% | 0 |
| February 2026 | 28 | 28 | 82.1% | 0 |
| March 2026 | 28 | 28 | 57.1% | 0 |
| April 2026 | 28 | 28 | 50.0% | 0 |
| May 2026 | 26 | 26 | 69.2% | 0 |
| June 2026 | 19 | 19 | 52.6% | 0 |
| July 2026 | 18 | 18 | 38.9% | 0 |