OnTimeStats

Historical on-time performance

Aspen to San Francisco

848 miData through May 2026Source: US DOT · BTS

Flights on ASE–SFO arrive on time 66% of the time over the last 12 months.

On-time rate66%arrived within 15 min
p90 delay115 min1 in 10 flights is worse (tail risk)
Cancelled6.6%of scheduled flights

based on 302 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • SkyWest Airlines
    On-time66%
    Medianon time
    p90115 min
    Cancel6.6%
    Flights302

Why flights run late

Delay causes

  • Airline27%
  • Weather6%
  • Air traffic (NAS)35%
  • Late aircraft33%
  • Security0%

Most delay minutes here are attributed to Air traffic (NAS).

When flights don't go

Why flights were cancelled

  • Airline0%
  • Weather95%
  • Air traffic (NAS)5%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 20 cancellations with a reported cause (BTS reports causes from June 2003).

Over time

On-time trend

By season

On-time rate by month

When to fly

Best time to fly ASE → SFO

All airlines · rolling 36 months (2023-06 .. 2026-05).

Best time of day

Mornings are the most reliable time of day to fly this route — 70% on time.

  • Mornings70% on time · p90 70 min · 392 flights
  • Middays59% on time · p90 145 min · 266 flights
  • Afternoons57% on time · p90 80 min · 137 flights · limited
  • Evenings53% on time · p90 115 min · 275 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 51% to 75% on time.

  • Wednesdays75% on time · p90 60 min · 138 flights · limited
  • Tuesdays72% on time · p90 45 min · 138 flights · limited
  • Thursdays63% on time · p90 100 min · 152 flights · limited
  • Saturdays60% on time · p90 95 min · 169 flights · limited
  • Mondays57% on time · p90 125 min · 151 flights · limited
  • Sundays55% on time · p90 95 min · 165 flights · limited
  • Fridays51% on time · p90 125 min · 157 flights · limited

Keep exploring

Related pages

Methodology

A flight is on time when it arrives within 15 minutes of schedule — the US DOT / BTS standard. Median and p90(the “1-in-10 bad day”) are read from the full arrival-delay distribution, never averaged across periods.

Figures cover a carrier’s own BTS-coded flights. Cells below ~200 flights are flagged as limited data. All numbers are pre-computed from public BTS On-Time Performance data.