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(UA) United Airlines 4539 On-Time Performance Rating

Date Range:

01-Aug-2025 to 30-Sep-2025

(IAD) Washington Dulles International Airport

Dulles, VA, US

(PHL) Philadelphia International Airport

Philadelphia, PA, US

On-Time Performance Chart

(using rounded numbers)
On-Time
44
73%
Late
1
2%
Very Late
2
3%
Excessive
11
18%
Cancelled
2
3%
Diverted
0
0%

Delay Statistics

(Aggregate Arrival Delay Statistics for this Flight)

Total Flights Observed
60
Total Delays ( > 1 min )
25
Codeshares
60
Average Delay (min.)
80.72
Standard Deviation
93
Min
0
Max
252

UA 4539 On-Time Performance Details

Overall Rating
0.6 of 5
Poor
Percentage On-Time 73%
Average Delay Time 80.72 min
FlightStats Rating is a merit measurement considering both on-time performance and delay severity. The score, 0.6 shows that this flight has on-time performance characteristics better than 11% of all other flights in the FlightStats database.
On-Time Performance Rating
1.2 of 5
Poor
Percentage On-Time 73%
This flight has an on-time performance of 73%. Statistically, when taking into consideration sample size, standard deviation, and mean, this flight is on-time more often than 24% of other flights.
Delay Performance
0.0 of 5
Very Poor
Average Delay Time 80.72 min
This flight has an average delay of 80.72 minutes with a standard deviation of 93 minutes. Statistically, when taking into consideration sample size, standard deviation, and mean, this flight has delay performance characteristics better than 0% of other flights.