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Flight Reliability

WN 3979 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 3979 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

75%
Arrive within 15 minutes
9 min
Average arrival delay
1.3%
Cancelled
2 min early
Median arrival delay

Based on 312 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon70%(43 flights)
  • Tue66%(44 flights)
  • Wed76%(41 flights)
  • Thu72%(43 flights)
  • Fri75%(44 flights)
  • Sat91%(44 flights)
  • Sun72%(47 flights)
On-time by departure window
  • 3–6 AM92%(38 flights)
  • 6–9 AM79%(19 flights)
  • 9 AM–12 PM92%(76 flights)
  • 12–3 PM65%(66 flights)
  • 3–6 PM63%(60 flights)
  • 6–9 PM75%(32 flights)
  • 9 PM–12 AM20%(15 flights)
On-time trend by month
48%
May

Jun 56% → May 48% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202556%27
July 202553%30
August 202567%12
October 202574%31
November 202596%27
December 2025100%31
January 202689%36
February 202688%42
March 202647%19
April 202658%19
May 202648%23
Departures on time
74%
Diverted
0.6%
Flights flown
306
Months covered
12

Keep nerding

Based on 312 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.