Flight Reliability
DL 429 · Delta Air Lines
Seattle → New York (SEA–JFK)
75
Usually Fine
WanderNerd Reliability Score
- 88%
- Arrive within 15 minutes
- 3 min
- Average arrival delay
- 3.3%
- Cancelled
- 10 min early
- Median arrival delay
Based on 365 historical flights. Data through May 2026.
What the data says
Sunday scaries are real for this one.
DL 429 arrived on time 92% of the time on Wednesdays. On Sundays: 84%.
Better than the SEA–JFK route average.
DL 429 arrived on time 88% of the time, versus 74% across the SEA–JFK route.
A bit ahead of the Delta Air Lines network.
DL 429 arrived on time 88% of the time, versus 81% across the Delta Air Lines network.
Keep a backup plan handy.
DL 429 was cancelled 3.3% of the time. Typical for U.S. flights is around 1–2%.
The breakdown
- Mon86%(50 flights)
- Tue86%(51 flights)
- Wed92%(51 flights)
- Thu90%(50 flights)
- Fri86%(49 flights)
- Sat89%(45 flights)
- Sun84%(50 flights)
86%
May
Jun 93% → May 86% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 93% | 30 |
| July 2025 | 90% | 30 |
| August 2025 | 87% | 30 |
| September 2025 | 97% | 29 |
| October 2025 | 90% | 30 |
| November 2025 | 79% | 29 |
| December 2025 | 89% | 28 |
| January 2026 | 72% | 29 |
| February 2026 | 88% | 25 |
| March 2026 | 89% | 28 |
| April 2026 | 90% | 29 |
| May 2026 | 86% | 29 |
- Departures on time
- 92%
- Diverted
- 1.9%
- Flights flown
- 346
- Months covered
- 12
Same route, other flights
Keep nerding
Based on 365 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.