DL977
Delta Air Lines flight 977 — Boston (BOS) to San Francisco (SFO)
On time
77%
Avg delay
~78 min
Cancelled
1.0%
DL977 is fairly reliable, though delays happen. About 77% of departures arrive on time. When delays happen, the most common cause is airline operations.
Monthly breakdown
| Month | On time | Cancelled | Avg delay |
|---|---|---|---|
| 2026-07 | 81% | 0.0% | 80 min |
| 2026-07 | 48% | 0.0% | 73 min |
| 2026-06 | 77% | 0.0% | 61 min |
| 2026-06 | 53% | 0.0% | 85 min |
| 2026-05 | 87% | 0.0% | 33 min |
| 2026-05 | 65% | 0.0% | 54 min |
| 2026-04 | 89% | 3.6% | 22 min |
| 2026-04 | 44% | 3.6% | 39 min |
| 2026-03 | 89% | 0.0% | 29 min |
| 2026-03 | 74% | 0.0% | 68 min |
| 2026-02 | 85% | 9.1% | 41 min |
| 2026-02 | 75% | 9.1% | 248 min |
Top delay cause
airline operations
Based on 2,134 tracked departures
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Get a free briefingData last updated October 2026. Source: Bureau of Transportation Statistics.