Flight Reliability
UA 4977 · United Airlines
Washington → Syracuse (IAD–SYR)
55
A Little Dicey
WanderNerd Reliability Score
- 76%
- Arrive within 15 minutes
- 23 min
- Average arrival delay
- 5.2%
- Cancelled
- 6 min early
- Median arrival delay
Based on 191 historical flights. Data through May 2026.
What the data says
Tuesday is the weak spot.
UA 4977 arrived on time 83% of the time on Mondays. On Tuesdays: 68%.
A bit behind the United Airlines network.
UA 4977 arrived on time 76% of the time, versus 79% across the United Airlines network.
Keep a backup plan handy.
UA 4977 was cancelled 5.2% of the time. Typical for U.S. flights is around 1–2%.
Ticking up lately.
UA 4977 arrived on time 82% of the time over the last three months in the data, compared with 76% in the three months before that.
The breakdown
- Mon83%(23 flights)
- Tue68%(22 flights)
- Wed69%(26 flights)
- Thu79%(28 flights)
- Fri79%(29 flights)
- Sat79%(24 flights)
- Sun71%(28 flights)
86%
May
Jun 59% → May 86% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 59% | 29 |
| July 2025 | 72% | 25 |
| August 2025 | 72% | 18 |
| January 2026 | 82% | 17 |
| March 2026 | 70% | 27 |
| April 2026 | 89% | 28 |
| May 2026 | 86% | 28 |
- Departures on time
- 79%
- Diverted
- 0.5%
- Flights flown
- 180
- Months covered
- 8
Same route, other flights
Keep nerding
Based on 191 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.