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Flight Reliability

DL 4279 · Delta Air Lines

Salt Lake City → SGU (SLC–SGU)

100
Nerd Approved
WanderNerd Reliability Score
93%
Arrive within 15 minutes
5 min early
Average arrival delay
0%
Cancelled
13 min early
Median arrival delay

Based on 363 historical flights. Data through May 2026.

What the data says

Skip Monday if you can.

DL 4279 arrived on time 98% of the time on Wednesdays. On Mondays: 89%.

Better than the Delta Air Lines network average.

DL 4279 arrived on time 93% of the time, versus 81% across the Delta Air Lines network.

It basically never cancels.

Out of 363 scheduled flights, only 0.0% were cancelled.

The breakdown

On-time by weekday
  • Mon89%(52 flights)
  • Tue94%(52 flights)
  • Wed98%(51 flights)
  • Thu92%(51 flights)
  • Fri92%(52 flights)
  • Sat94%(52 flights)
  • Sun93%(53 flights)
On-time by departure window
  • 12–3 PM—(1 flights)
  • 6–9 PM92%(221 flights)
  • 9 PM–12 AM94%(141 flights)
On-time trend by month
94%
May

Jun 93% → May 94% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202593%30
July 202581%31
August 2025100%31
September 202597%30
October 202590%31
November 202597%30
December 202597%29
January 202684%31
February 202696%28
March 202690%31
April 2026100%30
May 202694%31
Departures on time
93%
Diverted
0%
Flights flown
363
Months covered
12

Same route, other flights

Keep nerding

Based on 363 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.