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Flight Reliability

WN 1639 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 1639 moved between routes during this period. Numbers below combine all of them, so treat them as background, not a verdict. For a cleaner answer, check the route you are actually flying.

Combined across all its routes

80%
Arrive within 15 minutes
6 min
Average arrival delay
1.2%
Cancelled
5 min early
Median arrival delay

Based on 321 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon83%(47 flights)
  • Tue86%(42 flights)
  • Wed77%(43 flights)
  • Thu79%(48 flights)
  • Fri78%(50 flights)
  • Sat81%(41 flights)
  • Sun74%(46 flights)
On-time by departure window
  • 6–9 AM100%(31 flights)
  • 9 AM–12 PM84%(56 flights)
  • 12–3 PM87%(37 flights)
  • 3–6 PM90%(48 flights)
  • 6–9 PM71%(93 flights)
  • 9 PM–12 AM64%(52 flights)
On-time trend by month
73%
May

Jun 64% → May 73% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202564%28
July 202569%29
August 202582%22
September 2025100%21
October 202585%26
November 202584%19
January 202689%45
February 202679%34
March 202685%33
April 202662%26
May 202673%26
Departures on time
75%
Diverted
0%
Flights flown
317
Months covered
12

Keep nerding

Based on 321 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.