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Flight Reliability

DL 866 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 866 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
5 min
Average arrival delay
1.4%
Cancelled
7 min early
Median arrival delay

Based on 641 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon79%(89 flights)
  • Tue79%(89 flights)
  • Wed78%(91 flights)
  • Thu79%(92 flights)
  • Fri74%(90 flights)
  • Sat82%(90 flights)
  • Sun73%(89 flights)
On-time by departure window
  • 6–9 AM84%(38 flights)
  • 12–3 PM79%(345 flights)
  • 3–6 PM87%(102 flights)
  • 6–9 PM67%(145 flights)
On-time trend by month
71%
May

Jun 66% → May 71% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202566%56
July 202582%55
August 202582%62
September 202583%60
October 202588%60
November 202593%57
December 202573%48
January 202653%30
February 202696%28
March 202662%53
April 202678%59
May 202671%62
Departures on time
79%
Diverted
0.3%
Flights flown
630
Months covered
12

Keep nerding

Based on 641 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.