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Flight Reliability

DL 3821 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 3821 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

92%
Arrive within 15 minutes
7 min early
Average arrival delay
1.1%
Cancelled
13 min early
Median arrival delay

Based on 625 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon90%(90 flights)
  • Tue98%(90 flights)
  • Wed92%(88 flights)
  • Thu89%(89 flights)
  • Fri92%(87 flights)
  • Sat92%(85 flights)
  • Sun92%(89 flights)
On-time by departure window
  • 6–9 AM92%(293 flights)
  • 9 AM–12 PM93%(309 flights)
  • 12–3 PM79%(14 flights)
  • 3–6 PM—(2 flights)
On-time trend by month
92%
May

Jun 93% → May 92% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202593%60
July 202598%62
August 202598%62
September 202597%60
October 202597%62
November 202595%58
December 202592%50
January 202686%28
February 202674%46
March 202681%58
April 202693%60
May 202692%12
Departures on time
92%
Diverted
0%
Flights flown
618
Months covered
12

Keep nerding

Based on 625 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.