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Flight Reliability

DL 3994 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 3994 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
1 min early
Average arrival delay
0.7%
Cancelled
8 min early
Median arrival delay

Based on 595 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon89%(88 flights)
  • Tue91%(85 flights)
  • Wed87%(83 flights)
  • Thu93%(85 flights)
  • Fri82%(81 flights)
  • Sat89%(80 flights)
  • Sun83%(89 flights)
On-time by departure window
  • 6–9 AM78%(91 flights)
  • 9 AM–12 PM77%(60 flights)
  • 12–3 PM76%(25 flights)
  • 3–6 PM93%(403 flights)
  • 6–9 PM67%(12 flights)
On-time trend by month
79%
May

Jun 90% → May 79% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202590%60
July 202593%60
August 202595%58
September 202596%50
October 202593%60
November 202589%52
December 202596%47
January 202666%44
February 202674%42
March 202688%32
April 202683%30
May 202679%56
Departures on time
89%
Diverted
0%
Flights flown
591
Months covered
12

Keep nerding

Based on 595 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.