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Flight Reliability

DL 5603 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 5603 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

83%
Arrive within 15 minutes
6 min
Average arrival delay
3.1%
Cancelled
11 min early
Median arrival delay

Based on 326 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon89%(44 flights)
  • Tue82%(44 flights)
  • Wed95%(42 flights)
  • Thu88%(43 flights)
  • Fri72%(46 flights)
  • Sat84%(45 flights)
  • Sun72%(50 flights)
On-time by departure window
  • 6–9 AM90%(212 flights)
  • 9 AM–12 PM77%(26 flights)
  • 12–3 PM—(4 flights)
  • 3–6 PM—(3 flights)
  • 6–9 PM62%(69 flights)
On-time trend by month
80%
May

Jun 94% → May 80% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202594%36
July 202597%31
August 2025100%30
September 202597%30
October 202583%30
November 202597%29
December 202572%39
January 202650%10
March 202638%16
April 202663%27
May 202680%30
Departures on time
85%
Diverted
0.6%
Flights flown
314
Months covered
12

Keep nerding

Based on 326 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.