ON TIMEBOARD

UA 5851 on time

United Airlines 5851: Aspen to Los Angeles at 10:00 a.m. (past 12 months)

On time
79%
164 flights · likely 72–85%
Cancelled
1.8%
of scheduled flights
Typical arrival
−9 min
median vs schedule
When late
+101 min
average delay
Similar flights
79%
UA, same route & hour

About 1 in 5 UA 5851 flights from Aspen arrived 15+ minutes late, diverted or cancelled over the past year (21%); 1.8% were cancelled. The typical flight landed 9 minutes early.

UA 5851: ASE → LAX

Scheduled to leave Aspen at 10:00 a.m. local time, operated by SkyWest as OO 5851. Over the past year it arrived on time 79% of the time (164 flights), in line with other UA flights on the route at that hour (79%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Apr 2025: 87% on time (30 flights)87AprJun 2025: 72% on time (29 flights)72JunJul 2025: 81% on time (31 flights)81JulAug 2025: 74% on time (31 flights)74AugSep 2025: 87% on time (30 flights)87SepOct 2025: 72% on time (25 flights)72OctDec 2025: too few flights (13 flights)DecJan 2026: too few flights (5 flights)JanFeb 2026: 65% on time (17 flights)65FebMar 2026: 97% on time (31 flights)97MarApr 2026: 82% on time (22 flights)82AprAug 2026: 81% on time (21 flights)81Aug

By day of week

DayFlightsOn time
Monday2483%
Tuesday2383%
Wednesday2378%
Thursday2383%
Friday2475%
Saturday2471%
Sunday2383%

Why it was late

Airline (crew, maintenance, ops) 58%Severe weather 17%Air traffic & airport (NAS) 13%Late inbound plane 12%

All flights ASE → LAX · Connecting off UA 5851? Check the risk

Questions

How often is UA 5851 from ASE to LAX late?

United Airlines 5851 from Aspen, CO to Los Angeles, CA arrived 15 or more minutes late, was diverted or was cancelled on 21% of 164 scheduled flights between September 2025 and August 2026. 1.8% 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.