background

(UA) United Airlines 4257 On-Time Performance Rating

Date Range:

01-Mar-2026 to 30-Apr-2026

(IAD) Washington Dulles International Airport

Dulles, VA, US

(TYS) Knoxville McGhee Tyson Airport

Knoxville, TN, US

On-Time Performance Chart

(using rounded numbers)
On-Time
41
91%
Late
2
4%
Very Late
0
0%
Excessive
2
4%
Cancelled
0
0%
Diverted
0
0%

Delay Statistics

(Aggregate Arrival Delay Statistics for this Flight)

Total Flights Observed
45
Total Delays ( > 1 min )
5
Codeshares
45
Average Delay (min.)
80.4
Standard Deviation
86
Min
0
Max
175

UA 4257 On-Time Performance Details

Overall Rating
2.5 of 5
Average
Percentage On-Time 91%
Average Delay Time 80.4 min
FlightStats Rating is a merit measurement considering both on-time performance and delay severity. The score, 2.5 shows that this flight has on-time performance characteristics better than 49% of all other flights in the FlightStats database.
On-Time Performance Rating
4.9 of 5
Very Good
Percentage On-Time 91%
This flight has an on-time performance of 91%. Statistically, when taking into consideration sample size, standard deviation, and mean, this flight is on-time more often than 98% of other flights.
Delay Performance
0.1 of 5
Very Poor
Average Delay Time 80.4 min
This flight has an average delay of 80.4 minutes with a standard deviation of 86 minutes. Statistically, when taking into consideration sample size, standard deviation, and mean, this flight has delay performance characteristics better than 2% of other flights.

Other Stops for UA 4257