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Flight Reliability

DL 1309 · Delta Air Lines

Atlanta → Washington (ATL–IAD)91% of its flights flew this route. The rest (IAD–ATL) are included in these numbers.

74
Usually Fine
WanderNerd Reliability Score
77%
Arrive within 15 minutes
14 min
Average arrival delay
2.4%
Cancelled
0 min
Median arrival delay

Based on 287 historical flights. Data through May 2026.

What the data says

The late departure is the smart one here.

DL 1309 departing between 9 PM–12 AM arrived on time 93% of the time, versus 72% between 6–9 PM.

Friday is doing you no favors.

DL 1309 arrived on time 90% of the time on Saturdays and just 67% on Fridays. That gap is worth planning around.

A bit behind the Delta Air Lines network.

DL 1309 arrived on time 77% of the time, versus 81% across the Delta Air Lines network.

Recent months have been rougher.

DL 1309 arrived on time 67% of the time over the last three months in the data, compared with 89% in the three months before that.

The breakdown

On-time by weekday
  • Mon81%(48 flights)
  • Tue74%(34 flights)
  • Wed78%(36 flights)
  • Thu80%(55 flights)
  • Fri67%(49 flights)
  • Sat90%(10 flights)
  • Sun79%(48 flights)
On-time by departure window
  • 12–3 PM92%(25 flights)
  • 3–6 PM89%(26 flights)
  • 6–9 PM72%(200 flights)
  • 9 PM–12 AM93%(29 flights)
On-time trend by month
58%
May

Jun 61% → May 58% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202561%18
July 202543%14
August 202554%13
September 2025100%13
October 202597%29
November 202583%29
December 202582%22
January 202695%21
February 202689%36
March 202673%33
April 202669%26
May 202658%26
Departures on time
79%
Diverted
0%
Flights flown
280
Months covered
12

Same route, other flights

Keep nerding

Based on 287 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.