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Flight Reliability

DL 978 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 978 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
2 min early
Average arrival delay
0.7%
Cancelled
8 min early
Median arrival delay

Based on 425 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon85%(60 flights)
  • Tue95%(61 flights)
  • Wed92%(60 flights)
  • Thu90%(61 flights)
  • Fri82%(61 flights)
  • Sat88%(57 flights)
  • Sun85%(61 flights)
On-time by departure window
  • 6–9 AM88%(195 flights)
  • 9 AM–12 PM94%(108 flights)
  • 12–3 PM92%(26 flights)
  • 9 PM–12 AM82%(92 flights)
On-time trend by month
58%
May

Jun 96% → May 58% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202596%53
July 202595%61
August 202583%41
September 202593%30
October 202587%31
November 202583%30
December 202581%31
January 202690%30
February 202691%23
March 202693%30
April 202697%30
May 202658%31
Departures on time
88%
Diverted
0.2%
Flights flown
421
Months covered
12

Keep nerding

Based on 425 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.