OnTimeStats

Historical on-time performance

Portland to Detroit

1,953 miData through May 2026Source: US DOT · BTS

Flights on PDX–DTW arrive on time 78% of the time over the last 12 months.

On-time rate78%arrived within 15 min
p90 delay30 min1 in 10 flights is worse (tail risk)
Cancelled0.9%of scheduled flights

based on 339 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • Delta Air Lines
    On-time78%
    Medianon time
    p9030 min
    Cancel0.9%
    Flights339

Why flights run late

Delay causes

  • Airline33%
  • Weather0%
  • Air traffic (NAS)8%
  • Late aircraft60%
  • Security0%

Most delay minutes here are attributed to Late aircraft.

When flights don't go

Why flights were cancelled

  • Airline100%
  • Weather0%
  • Air traffic (NAS)0%
  • Security0%

Most cancellations here are attributed to Airline. Shares are among 3 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 PDX → DTW

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

Best time of day

Middays are the most reliable time of day to fly this route — 85% on time.

  • Middays85% on time · p90 20 min · 539 flights
  • Overnights80% on time · p90 30 min · 512 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 76% to 90% on time.

  • Tuesdays90% on time · p90 10 min · 132 flights · limited
  • Fridays85% on time · p90 20 min · 172 flights · limited
  • Mondays85% on time · p90 20 min · 149 flights · limited
  • Wednesdays84% on time · p90 15 min · 132 flights · limited
  • Saturdays83% on time · p90 25 min · 133 flights · limited
  • Thursdays78% on time · p90 35 min · 166 flights · limited
  • Sundays76% on time · p90 40 min · 171 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.