WN3911
WN3911 (Southwest Airlines) is a multi-stop service on 22 routes, busiest Boston to Chicago. Of 457 departures recorded from October 2024 to July 2026, 68.9% left on time, according to the US BTS.
- On-time departures68.9%of 457 flights
- Average delay18.9 min
- July 202627▲ 3.8%vs July 2025
- Cancelled1.5%
- Legs flown under this number22
Recorded departures by month
All legs under this number combined; see the leg table.
Months without data are left blank.
The most recent periods18 periods
| Period | Departures 2025 | Departures 2026 | Change vs last year |
|---|---|---|---|
| January | 3 | 28 | ▲ 833.3% |
| February | – | 28 | – |
| March | 26 | 4 | ▼ 84.6% |
| April | 30 | 9 | ▼ 70.0% |
| May | 31 | 8 | ▼ 74.2% |
| June | 26 | 25 | ▼ 3.8% |
| July | 26 | 27 | ▲ 3.8% |
| August | 34 | – | – |
| September | 35 | – | – |
| October | 14 | – | in progress |
| November | 24 | – | – |
| December | 21 | – | – |
according to the US BTS · October 2024 → July 2026
On-time departures by month
Months without data are left blank.
On time = departure within 15 minutes of schedule. Non-cancelled flights with a recorded delay only.
The most recent periods18 periods
| Period | On time 2025 | On time 2026 | Change vs last year |
|---|---|---|---|
| January | 100.0% | 89.3% | ▼ 10.7% |
| February | – | 100.0% | – |
| March | 76.0% | 100.0% | ▲ 31.6% |
| April | 60.0% | 88.9% | ▲ 48.2% |
| May | 64.5% | 87.5% | ▲ 35.6% |
| June | 73.1% | 50.0% | ▼ 31.6% |
| July | 65.4% | 24.0% | ▼ 63.3% |
| August | 44.1% | – | – |
| September | 65.7% | – | – |
| October | 85.7% | – | in progress |
| November | 90.5% | – | – |
| December | 76.2% | – | – |
according to the US BTS · October 2024 → July 2026
Average departure delay by month
Months without data are left blank.
according to the US BTS · October 2024 → July 2026
Cancelled departures by month
Months without data are left blank.
The most recent periods18 periods
| Period | Cancelled 2025 | Cancelled 2026 | Change vs last year |
|---|---|---|---|
| January | 0 | 0 | – |
| February | – | 0 | – |
| March | 1 | 0 | ▼ 100.0% |
| April | 0 | 0 | – |
| May | 0 | 0 | – |
| June | 0 | 1 | – |
| July | 0 | 2 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 3 | – | – |
| December | 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 98.5% 450
- Cancelled 1.5% 7
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
7| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| BOS MDW Boston Logan International Airport – Chicago Midway International Airport | 1,381 | 47.6 min | 42.9% | 59 |
| TUS DEN Tucson International Airport – Denver International Airport | 1,029 | 0.3 min | 94.8% | 58 |
| LAX LAS Los Angeles International Airport – Harry Reid International Airport | 380 | 17.9 min | 60.3% | 58 |
| OKC DEN OKC Will Rogers World Airport – Denver International Airport | 796 | 27.8 min | 46.0% | 50 |
| OAK SNA Oakland San Francisco Bay Airport – John Wayne Orange County International Airport | 597 | 5.1 min | 85.7% | 45 |
| MDW SAT Chicago Midway International Airport – San Antonio International Airport | 1,668 | 30.1 min | 64.3% | 42 |
| ELP LAS El Paso International Airport – Harry Reid International Airport | 938 | 11.7 min | 78.1% | 33 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 18 | 18 | 72.2% | 0 |
| November 2024 | 29 | 29 | 65.5% | 0 |
| December 2024 | 11 | 11 | 63.6% | 0 |
| January 2025 | 3 | 3 | 100.0% | 0 |
| March 2025 | 26 | 25 | 76.0% | 1 |
| April 2025 | 30 | 30 | 60.0% | 0 |
| May 2025 | 31 | 31 | 64.5% | 0 |
| June 2025 | 26 | 26 | 73.1% | 0 |
| July 2025 | 26 | 26 | 65.4% | 0 |
| August 2025 | 34 | 34 | 44.1% | 0 |
| September 2025 | 35 | 35 | 65.7% | 0 |
| October 2025 | 14 | 14 | 85.7% | 0 |
| November 2025 | 24 | 21 | 90.5% | 3 |
| December 2025 | 21 | 21 | 76.2% | 0 |
| January 2026 | 28 | 28 | 89.3% | 0 |
| February 2026 | 28 | 28 | 100.0% | 0 |
| March 2026 | 4 | 4 | 100.0% | 0 |
| April 2026 | 9 | 9 | 88.9% | 0 |
| May 2026 | 8 | 8 | 87.5% | 0 |
| June 2026 | 25 | 24 | 50.0% | 1 |
| July 2026 | 27 | 25 | 24.0% | 2 |