ON TIMEBOARD

UA 1638 on time

United Airlines 1638: Denver to Los Angeles at 8:00 a.m. (past 12 months)

On time
92%
365 flights · likely 89–94%
Cancelled
0.0%
of scheduled flights
Typical arrival
−5 min
median vs schedule
When late
+30 min
average delay
Similar flights
92%
UA, same route & hour

About 1 in 12 UA 1638 flights from Denver arrived 15+ minutes late, diverted or cancelled over the past year (8%); 0.0% were cancelled. The typical flight landed 5 minutes early.

UA 1638: DEN → LAX

Scheduled to leave Denver at 8:00 a.m. local time. Over the past year it arrived on time 92% of the time (365 flights), in line with other UA flights on the route at that hour (92%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: 90% on time (30 flights)90SepOct 2025: 87% on time (31 flights)87OctNov 2025: 93% on time (30 flights)93NovDec 2025: 84% on time (31 flights)84DecJan 2026: 94% on time (31 flights)94JanFeb 2026: 93% on time (28 flights)93FebMar 2026: 87% on time (31 flights)87MarApr 2026: 100% on time (30 flights)100AprMay 2026: 94% on time (31 flights)94MayJun 2026: 90% on time (30 flights)90JunJul 2026: 90% on time (31 flights)90JulAug 2026: 100% on time (31 flights)100Aug

By day of week

DayFlightsOn time
Monday5387%
Tuesday5294%
Wednesday5296%
Thursday5296%
Friday5294%
Saturday5288%
Sunday5287%

Why it was late

Air traffic & airport (NAS) 57%Airline (crew, maintenance, ops) 22%Late inbound plane 20%

All flights DEN → LAX · Connecting off UA 1638? Check the risk

Questions

How often is UA 1638 from DEN to LAX late?

United Airlines 1638 from Denver, CO to Los Angeles, CA arrived 15 or more minutes late, was diverted or was cancelled on 8% of 365 scheduled flights between September 2025 and August 2026. 0.0% were cancelled.

Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check United Airlines for today's flight. Method.