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Flight Reliability

DL 489 · Delta Air Lines

Seattle → Raleigh–Durham (SEA–RDU)

78
Usually Fine
WanderNerd Reliability Score
77%
Arrive within 15 minutes
4 min
Average arrival delay
1.4%
Cancelled
4 min early
Median arrival delay

Based on 360 historical flights. Data through May 2026.

What the data says

3–6 PM has a slight edge.

Departures between 3–6 PM arrived on time 77% of the time, against 71% between 9 PM–12 AM.

Friday is doing you no favors.

DL 489 arrived on time 87% of the time on Tuesdays and just 67% on Fridays. That gap is worth planning around.

A bit behind the Delta Air Lines network.

DL 489 arrived on time 77% of the time, versus 81% across the Delta Air Lines network.

Slipping a little lately.

DL 489 arrived on time 75% of the time over the last three months in the data, compared with 81% in the three months before that.

The breakdown

On-time by weekday
  • Mon70%(50 flights)
  • Tue87%(52 flights)
  • Wed85%(52 flights)
  • Thu82%(51 flights)
  • Fri67%(51 flights)
  • Sat78%(46 flights)
  • Sun69%(52 flights)
On-time by departure window
  • 3–6 PM77%(340 flights)
  • 9 PM–12 AM71%(14 flights)
On-time trend by month
81%
May

Jun 73% → May 81% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202573%30
July 202571%31
August 202581%31
September 202580%30
October 202581%31
November 202569%26
December 202579%28
January 202686%29
February 202678%27
March 202673%30
April 202670%30
May 202681%31
Departures on time
83%
Diverted
0.3%
Flights flown
354
Months covered
12

Same route, other flights

Keep nerding

Based on 360 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.