Flight Reliability
DL 721 · Delta Air Lines
Santa Ana → Atlanta (SNA–ATL)
84
Pretty Reliable
WanderNerd Reliability Score
- 82%
- Arrive within 15 minutes
- 13 min
- Average arrival delay
- 0.8%
- Cancelled
- 3 min early
- Median arrival delay
Based on 365 historical flights. Data through May 2026.
What the data says
Tuesdays have been rough.
DL 721 arrived on time 89% of the time on Wednesdays and just 73% on Tuesdays. That gap is worth planning around.
Ticking up lately.
DL 721 arrived on time 81% of the time over the last three months in the data, compared with 75% in the three months before that.
The breakdown
- Mon84%(51 flights)
- Tue73%(52 flights)
- Wed89%(52 flights)
- Thu87%(52 flights)
- Fri82%(51 flights)
- Sat84%(50 flights)
- Sun76%(53 flights)
84%
May
Jun 90% → May 84% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 90% | 30 |
| July 2025 | 81% | 31 |
| August 2025 | 87% | 30 |
| September 2025 | 83% | 29 |
| October 2025 | 90% | 31 |
| November 2025 | 83% | 30 |
| December 2025 | 73% | 30 |
| January 2026 | 74% | 31 |
| February 2026 | 79% | 28 |
| March 2026 | 73% | 30 |
| April 2026 | 87% | 30 |
| May 2026 | 84% | 31 |
- Departures on time
- 86%
- Diverted
- 0.3%
- Flights flown
- 361
- 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.