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Flight Reliability

WN 4159 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 4159 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

78%
Arrive within 15 minutes
6 min
Average arrival delay
1.1%
Cancelled
2 min early
Median arrival delay

Based on 267 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon76%(42 flights)
  • Tue80%(35 flights)
  • Wed68%(37 flights)
  • Thu70%(43 flights)
  • Fri80%(39 flights)
  • Sat97%(33 flights)
  • Sun79%(33 flights)
On-time by departure window
  • 3–6 AM88%(17 flights)
  • 6–9 AM96%(98 flights)
  • 12–3 PM63%(72 flights)
  • 3–6 PM56%(25 flights)
  • 6–9 PM71%(48 flights)
  • 9 PM–12 AM—(2 flights)
On-time trend by month
78%
May

Jun 84% → May 78% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202584%19
July 202557%21
August 202593%29
September 202597%30
November 202586%22
December 202572%18
February 202653%15
March 202655%29
April 202679%33
May 202678%36
Departures on time
74%
Diverted
0.7%
Flights flown
262
Months covered
12

Keep nerding

Based on 267 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.