Flight OddsAA4778 BOS → ORD
American Airlines · Boston, MA to Chicago, IL · 9 flights observed, 2025-07-08 to 2025-08-05 · 867 mi
AA4778 covers more than one route in the data window — the stats below are for BOS → ORD, the one it has flown most recently. The others are linked under “Other routes”.
On-time arrival
38%
Median delay
+23 min
90th percentile
+81 min
Cancellation rate
11%
How often is AA4778 on time?
Across 9 flights on BOS → ORD from 2025-07-08 to 2025-08-05, AA4778 arrived within 15 minutes of schedule 38% of the time. The median arrival delay was +23 min, and the worst 10% of flights arrived +81 min or later. 11% of flights were cancelled.
Delay distribution
Arrival delay for completed flights (excludes cancellations and diversions).
| Arrival | Flights | Share |
|---|---|---|
| Early / on-time | 3 | 38% |
| 16-30 min | 2 | 25% |
| 31-60 min | 1 | 13% |
| 61-120 min | 2 | 25% |
| 2+ hrs | 0 | 0% |
Performance by month
| Month | Flights | On-time | Avg delay |
|---|---|---|---|
| 2025-07 | 7 | 43% | +35 min |
| 2025-08 | 1 | 0% | +27 min |
Performance by day of week
| Day | Flights | On-time |
|---|---|---|
| Mon | No data | — |
| Tue | 5 | 40% |
| Wed | 3 | 33% |
| Thu | No data | — |
| Fri | No data | — |
| Sat | No data | — |
| Sun | No data | — |
Other routes
Related
Based on US Department of Transportation Bureau of Transportation Statistics on-time data. Loading live conditions and full charts…