Skip to content
WanderNerd
Check a flight

Flight Reliability

DL 4120 · Delta Air Lines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and DL 4120 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

84%
Arrive within 15 minutes
1 min
Average arrival delay
0.3%
Cancelled
9 min early
Median arrival delay

Based on 352 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon85%(59 flights)
  • Tue93%(55 flights)
  • Wed82%(55 flights)
  • Thu82%(56 flights)
  • Fri80%(55 flights)
  • Sat88%(16 flights)
  • Sun82%(55 flights)
On-time by departure window
  • 9 AM–12 PM—(1 flights)
  • 12–3 PM84%(188 flights)
  • 3–6 PM83%(95 flights)
  • 6–9 PM85%(67 flights)
On-time trend by month
80%
May

Jun 88% → May 80% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202588%24
July 202580%49
August 202587%38
September 202579%34
October 202583%46
November 202586%36
January 202693%27
February 202682%28
April 202694%16
May 202680%44
Departures on time
84%
Diverted
0%
Flights flown
351
Months covered
12

Keep nerding

Based on 352 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.