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Flight Reliability

DL 1238 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 1238 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

91%
Arrive within 15 minutes
3 min early
Average arrival delay
2.8%
Cancelled
10 min early
Median arrival delay

Based on 395 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon97%(61 flights)
  • Tue93%(61 flights)
  • Wed95%(59 flights)
  • Thu89%(55 flights)
  • Fri92%(61 flights)
  • Sat78%(36 flights)
  • Sun84%(51 flights)
On-time by departure window
  • 6–9 AM90%(179 flights)
  • 3–6 PM89%(92 flights)
  • 6–9 PM93%(113 flights)
On-time trend by month
90%
May

Jun 88% → May 90% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202588%32
July 202591%23
August 202593%29
September 202593%30
October 202593%30
November 202590%29
December 202579%33
January 202685%26
February 202692%13
March 202692%39
April 202698%52
May 202690%48
Departures on time
91%
Diverted
0%
Flights flown
384
Months covered
12

Keep nerding

Based on 395 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.