DL977
DL977 (Delta Air Lines) is a multi-stop service on 6 routes, busiest Boston to San Francisco. Of 987 departures recorded from October 2024 to July 2026, 76.2% left on time, according to the US BTS.
- On-time departures76.2%of 987 flights
- Average delay16.4 min
- July 202662▲ 463.6%vs July 2025
- Cancelled1.0%
- Legs flown under this number6
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 | 49 | 47 | ▼ 4.1% |
| February | 45 | 44 | ▼ 2.2% |
| March | 52 | 54 | ▲ 3.8% |
| April | 56 | 56 | 0.0% |
| May | 62 | 62 | 0.0% |
| June | 19 | 60 | ▲ 215.8% |
| July | 11 | 62 | ▲ 463.6% |
| August | 25 | – | – |
| September | 30 | – | – |
| October | 31 | – | in progress |
| November | 29 | – | – |
| December | 36 | – | – |
| Year to date (Jan–Jul) | 294 | 385 | ▲ 31.0% |
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 | 79.6% | 68.2% | ▼ 14.3% |
| February | 73.3% | 77.5% | ▲ 5.7% |
| March | 82.7% | 79.6% | ▼ 3.7% |
| April | 87.5% | 75.9% | ▼ 13.2% |
| May | 71.0% | 80.7% | ▲ 13.6% |
| June | 79.0% | 78.3% | ▼ 0.8% |
| July | 90.9% | 74.2% | ▼ 18.4% |
| August | 72.0% | – | – |
| September | 70.0% | – | – |
| October | 58.1% | – | in progress |
| November | 65.5% | – | – |
| December | 71.4% | – | – |
| Year-to-date average (Jan–Jul) | 80.6% | 76.3% | ▼ 5.2% |
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 | 3 | – |
| February | 0 | 4 | – |
| March | 0 | 0 | – |
| April | 0 | 2 | – |
| May | 0 | 0 | – |
| June | 0 | 0 | – |
| July | 0 | 0 | – |
| August | 0 | – | – |
| September | 0 | – | – |
| October | 0 | – | in progress |
| November | 0 | – | – |
| December | 1 | – | – |
| Year to date (Jan–Jul) | 0 | 9 |
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 99.0% 977
- Cancelled 1.0% 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
3| Routes | Distance (km) | Avg delay | On time | Departures |
|---|---|---|---|---|
| BOS SFO Boston Logan International Airport – San Francisco International Airport | 4,341 | 8.8 min | 84.5% | 424 |
| SFO BOS San Francisco International Airport – Boston Logan International Airport | 4,341 | 22.3 min | 70.4% | 410 |
| MCO ATL Orlando International Airport – Hartsfield Jackson Atlanta International Airport | 651 | 25.1 min | 65.1% | 130 |
Monthly figures
| Period | Departures | With departure delay recorded | On time | Cancelled |
|---|---|---|---|---|
| October 2024 | 40 | 40 | 75.0% | 0 |
| November 2024 | 60 | 60 | 78.3% | 0 |
| December 2024 | 57 | 57 | 79.0% | 0 |
| January 2025 | 49 | 49 | 79.6% | 0 |
| February 2025 | 45 | 45 | 73.3% | 0 |
| March 2025 | 52 | 52 | 82.7% | 0 |
| April 2025 | 56 | 56 | 87.5% | 0 |
| May 2025 | 62 | 62 | 71.0% | 0 |
| June 2025 | 19 | 19 | 79.0% | 0 |
| July 2025 | 11 | 11 | 90.9% | 0 |
| August 2025 | 25 | 25 | 72.0% | 0 |
| September 2025 | 30 | 30 | 70.0% | 0 |
| October 2025 | 31 | 31 | 58.1% | 0 |
| November 2025 | 29 | 29 | 65.5% | 0 |
| December 2025 | 36 | 35 | 71.4% | 1 |
| January 2026 | 47 | 44 | 68.2% | 3 |
| February 2026 | 44 | 40 | 77.5% | 4 |
| March 2026 | 54 | 54 | 79.6% | 0 |
| April 2026 | 56 | 54 | 75.9% | 2 |
| May 2026 | 62 | 62 | 80.7% | 0 |
| June 2026 | 60 | 60 | 78.3% | 0 |
| July 2026 | 62 | 62 | 74.2% | 0 |