Flight Reliability
DL 3243 · Delta Air Lines
New York → Denver (JFK–DEN)
38
Bring Snacks
WanderNerd Reliability Score
- 55%
- Arrive within 15 minutes
- 30 min
- Average arrival delay
- 2.7%
- Cancelled
- 9 min
- Median arrival delay
Based on 183 historical flights. Data through May 2026.
What the data says
Friday is doing you no favors.
DL 3243 arrived on time 68% of the time on Tuesdays and just 44% on Fridays. That gap is worth planning around.
Well behind the JFK–DEN route.
DL 3243 arrived on time 55% of the time, versus 71% across the JFK–DEN route.
Well behind the Delta Air Lines network.
DL 3243 arrived on time 55% of the time, versus 81% across the Delta Air Lines network.
Recent months have been rougher.
DL 3243 arrived on time 54% of the time over the last three months in the data, compared with 64% in the three months before that.
The breakdown
- Mon48%(27 flights)
- Tue68%(28 flights)
- Wed63%(27 flights)
- Thu48%(25 flights)
- Fri44%(27 flights)
- Sat56%(16 flights)
- Sun58%(26 flights)
- 3–6 PM56%(174 flights)
- 6–9 PM—(2 flights)
47%
Dec
Jun 22% → Dec 47% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 22% | 23 |
| July 2025 | 41% | 27 |
| August 2025 | 69% | 29 |
| September 2025 | 83% | 29 |
| October 2025 | 48% | 27 |
| November 2025 | 67% | 24 |
| December 2025 | 47% | 17 |
- Departures on time
- 67%
- Diverted
- 1.1%
- Flights flown
- 176
- Months covered
- 7
Same route, other flights
Keep nerding
Based on 183 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.