(UA) United Airlines 4520 On-Time Performance Rating

Date Range:

15-Aug-2026 to 15-Oct-2026

(PHL) Philadelphia International Airport

Philadelphia, PA, US

(IAD) Washington Dulles International Airport

Dulles, VA, US

On-Time Performance Chart

(using rounded numbers)

On-Time

89%

Late

11%

Very Late

Excessive

Cancelled

Diverted

Delay Statistics

(Aggregate Arrival Delay Statistics for this Flight)

Total Flights Observed

Total Delays ( > 1 min )

Codeshares

Average Delay (min.)

8.333333333333334

Standard Deviation

Min

Max

UA 4520 On-Time Performance Details

Overall Rating

4.0 of 5

Good

Percentage On-Time 89%

Average Delay Time 8.333333333333334 min

FlightStats Rating is a merit measurement considering both on-time performance and delay severity. The score, 4 shows that this flight has on-time performance characteristics better than 79% of all other flights in the FlightStats database.

On-Time Performance Rating

4.1 of 5

Good

Percentage On-Time 89%

This flight has an on-time performance of 89%. Statistically, when taking into consideration sample size, standard deviation, and mean, this flight is on-time more often than 82% of other flights.

Delay Performance

3.9 of 5

Good

Average Delay Time 8.333333333333334 min

This flight has an average delay of 8.333333333333334 minutes with a standard deviation of 11 minutes. Statistically, when taking into consideration sample size, standard deviation, and mean, this flight has delay performance characteristics better than 79% of other flights.