Skip to content
WanderNerd
Check a flight

Flight Reliability

UA 4566 · United Airlines

SCE → Chicago (SCE–ORD)93% of its flights flew this route. The rest (PWM–IAD, ORD–SCE) are included in these numbers.

67
Usually Fine
WanderNerd Reliability Score
74%
Arrive within 15 minutes
22 min
Average arrival delay
1.7%
Cancelled
8 min early
Median arrival delay

Based on 350 historical flights. Data through May 2026.

What the data says

The 12–3 PM departure wins.

UA 4566 departing between 12–3 PM arrived on time 75% of the time, versus 47% between 9 AM–12 PM.

Sunday scaries are real for this one.

UA 4566 arrived on time 86% of the time on Fridays and just 67% on Sundays. That gap is worth planning around.

A bit behind the United Airlines network.

UA 4566 arrived on time 74% of the time, versus 79% across the United Airlines network.

Ticking up lately.

UA 4566 arrived on time 70% of the time over the last three months in the data, compared with 64% in the three months before that.

The breakdown

On-time by weekday
  • Mon75%(52 flights)
  • Tue77%(43 flights)
  • Wed71%(49 flights)
  • Thu76%(50 flights)
  • Fri86%(49 flights)
  • Sat67%(51 flights)
  • Sun67%(48 flights)
On-time by departure window
  • 6–9 AM—(5 flights)
  • 9 AM–12 PM47%(19 flights)
  • 12–3 PM75%(318 flights)
On-time trend by month
64%
May

Jun 75% → May 64% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202575%28
July 202574%31
August 202583%30
September 202587%30
October 202584%31
November 202579%29
December 202552%31
January 202657%21
February 202683%24
March 202677%30
April 202669%29
May 202664%28
Departures on time
74%
Diverted
0.6%
Flights flown
342
Months covered
12

Same route, other flights

Keep nerding

Based on 350 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.