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Flight Reliability

DL 1509 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 1509 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
3 min early
Average arrival delay
3.2%
Cancelled
10 min early
Median arrival delay

Based on 730 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon93%(100 flights)
  • Tue89%(102 flights)
  • Wed84%(101 flights)
  • Thu89%(104 flights)
  • Fri91%(101 flights)
  • Sat87%(99 flights)
  • Sun84%(99 flights)
On-time by departure window
  • 6–9 AM88%(289 flights)
  • 9 AM–12 PM88%(417 flights)
On-time trend by month
84%
May

Jun 83% → May 84% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202583%57
July 202589%62
August 202579%62
September 2025100%60
October 202595%62
November 202582%56
December 202586%62
January 202686%58
February 202682%56
March 202695%55
April 202697%60
May 202684%56
Departures on time
88%
Diverted
0.1%
Flights flown
706
Months covered
12

Keep nerding

Based on 730 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.