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Flight Reliability

DL 3959 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 3959 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

88%
Arrive within 15 minutes
1 min early
Average arrival delay
0.3%
Cancelled
11 min early
Median arrival delay

Based on 327 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon94%(48 flights)
  • Tue89%(47 flights)
  • Wed89%(47 flights)
  • Thu77%(47 flights)
  • Fri91%(46 flights)
  • Sat91%(44 flights)
  • Sun87%(47 flights)
On-time by departure window
  • 6–9 AM96%(26 flights)
  • 12–3 PM86%(109 flights)
  • 3–6 PM94%(104 flights)
  • 6–9 PM84%(55 flights)
  • 9 PM–12 AM78%(32 flights)
On-time trend by month
81%
May

Jun 100% → May 81% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 2025100%14
August 202591%21
September 202593%30
November 202586%14
December 202566%29
January 202690%58
February 202691%56
March 202692%37
April 202693%30
May 202681%31
Departures on time
89%
Diverted
0%
Flights flown
326
Months covered
11

Keep nerding

Based on 327 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.