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WanderNerd

Flight Reliability

DL 1551 · Delta Air Lines

Los Angeles → Seattle (LAXSEA)94% of its flights flew this route. The rest (ATL–PNS, PNS–ATL) are included in these numbers.

88
Pretty Reliable
WanderNerd Reliability Score
85%
Arrive within 15 minutes
1 min early
Average arrival delay
0.6%
Cancelled
12 min early
Median arrival delay

Based on 330 historical flights. Data through May 2026.

What the data says

Skip Tuesday if you can.

DL 1551 arrived on time 91% of the time on Fridays. On Tuesdays: 79%.

A bit ahead of the Delta Air Lines network.

DL 1551 arrived on time 85% of the time, versus 81% across the Delta Air Lines network.

Slipping a little lately.

DL 1551 arrived on time 82% of the time over the last three months in the data, compared with 88% in the three months before that.

The breakdown

On-time by weekday
  • Mon87%(52 flights)
  • Tue79%(38 flights)
  • Wed90%(49 flights)
  • Thu80%(50 flights)
  • Fri91%(53 flights)
  • Sat90%(31 flights)
  • Sun81%(53 flights)
On-time by departure window
  • 6–9 PM85%(325 flights)
  • 9 PM–12 AM(1 flights)
On-time trend by month
58%
May

Jun 93% → May 58% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202593%30
July 202579%29
August 202587%31
September 2025100%30
October 202570%30
November 202582%28
December 202591%35
January 202689%27
February 202683%18
March 202696%22
April 202691%22
May 202658%24
Departures on time
80%
Diverted
0.6%
Flights flown
326
Months covered
12

Based on 330 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.