Skip to content
WanderNerd
Check a flight

Flight Reliability

DL 3949 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 3949 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
21 min
Average arrival delay
0.5%
Cancelled
6 min early
Median arrival delay

Based on 407 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon82%(62 flights)
  • Tue71%(61 flights)
  • Wed69%(61 flights)
  • Thu83%(59 flights)
  • Fri81%(59 flights)
  • Sat70%(40 flights)
  • Sun68%(63 flights)
On-time by departure window
  • 3–6 AM96%(25 flights)
  • 6–9 AM83%(162 flights)
  • 9 AM–12 PM67%(33 flights)
  • 12–3 PM70%(33 flights)
  • 3–6 PM64%(108 flights)
  • 6–9 PM—(1 flights)
  • 9 PM–12 AM74%(43 flights)
On-time trend by month
89%
May

Jun 65% → May 89% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202565%23
July 202587%31
August 202590%10
September 202595%20
October 202591%43
November 202557%37
December 202566%58
January 202655%51
February 202663%24
March 202676%29
April 202691%44
May 202689%35
Departures on time
75%
Diverted
0%
Flights flown
405
Months covered
12

Keep nerding

Based on 407 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.