OnTimeStats

Historical on-time performance

San Francisco to Aspen

848 miData through May 2026Source: US DOT · BTS

Flights on SFO–ASE arrive on time 69% of the time over the last 12 months.

On-time rate69%arrived within 15 min
p90 delay95 min1 in 10 flights is worse (tail risk)
Cancelled3.0%of scheduled flights

based on 304 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • SkyWest Airlines
    On-time69%
    Medianon time
    p9095 min
    Cancel3.0%
    Flights304

Why flights run late

Delay causes

  • Airline46%
  • Weather9%
  • Air traffic (NAS)17%
  • Late aircraft28%
  • Security0%

Most delay minutes here are attributed to Airline.

When flights don't go

Why flights were cancelled

  • Airline11%
  • Weather78%
  • Air traffic (NAS)11%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 9 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 SFO → ASE

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

Best time of day

On-time rates are fairly even by time of day on this route — ranging from 55% to 69% on time.

  • Evenings69% on time · p90 25 min · 111 flights · limited
  • Afternoons69% on time · p90 75 min · 541 flights
  • Mornings55% on time · p90 125 min · 401 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 56% to 75% on time.

  • Wednesdays75% on time · p90 55 min · 140 flights · limited
  • Tuesdays70% on time · p90 90 min · 135 flights · limited
  • Saturdays64% on time · p90 110 min · 169 flights · limited
  • Thursdays63% on time · p90 80 min · 156 flights · limited
  • Mondays62% on time · p90 80 min · 151 flights · limited
  • Sundays61% on time · p90 100 min · 164 flights · limited
  • Fridays56% on time · p90 120 min · 160 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.