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Flight Reliability

DL 3947 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 3947 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

75%
Arrive within 15 minutes
23 min
Average arrival delay
1.4%
Cancelled
8 min early
Median arrival delay

Based on 354 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon84%(50 flights)
  • Tue65%(52 flights)
  • Wed80%(49 flights)
  • Thu69%(51 flights)
  • Fri60%(47 flights)
  • Sat76%(45 flights)
  • Sun89%(55 flights)
On-time by departure window
  • 6–9 AM85%(95 flights)
  • 9 AM–12 PM—(3 flights)
  • 12–3 PM—(3 flights)
  • 3–6 PM70%(116 flights)
  • 6–9 PM68%(120 flights)
  • 9 PM–12 AM92%(12 flights)
On-time trend by month
94%
May

Jun 50% → May 94% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202550%42
July 202567%57
August 202564%44
September 202574%34
December 202583%12
January 202670%30
February 202696%28
March 202686%28
April 202692%48
May 202694%18
Departures on time
76%
Diverted
0%
Flights flown
349
Months covered
11

Keep nerding

Based on 354 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.