Flight Reliability
UA 1240 · United Airlines
Dallas–Fort Worth → Washington (DFW–IAD)94% of its flights flew this route. The rest (ORD–FCA, SFO–EWR) are included in these numbers.
83
Pretty Reliable
WanderNerd Reliability Score
- 80%
- Arrive within 15 minutes
- 11 min
- Average arrival delay
- 1.1%
- Cancelled
- 5 min early
- Median arrival delay
Based on 348 historical flights. Data through May 2026.
What the data says
The 3–6 PM departure wins.
UA 1240 departing between 3–6 PM arrived on time 81% of the time, versus 58% between 6–9 AM.
Sunday scaries are real for this one.
UA 1240 arrived on time 84% of the time on Tuesdays. On Sundays: 75%.
Slipping a little lately.
UA 1240 arrived on time 78% of the time over the last three months in the data, compared with 84% in the three months before that.
The breakdown
- Mon77%(48 flights)
- Tue84%(45 flights)
- Wed77%(51 flights)
- Thu82%(51 flights)
- Fri84%(51 flights)
- Sat80%(46 flights)
- Sun75%(52 flights)
- 12–3 AM—(1 flights)
- 6–9 AM58%(19 flights)
- 3–6 PM81%(324 flights)
73%
May
Jun 77% → May 73% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 77% | 30 |
| July 2025 | 71% | 31 |
| August 2025 | 87% | 30 |
| September 2025 | 93% | 30 |
| October 2025 | 77% | 30 |
| November 2025 | 73% | 26 |
| December 2025 | 66% | 29 |
| January 2026 | 91% | 22 |
| February 2026 | 96% | 25 |
| March 2026 | 74% | 31 |
| April 2026 | 87% | 30 |
| May 2026 | 73% | 30 |
- Departures on time
- 78%
- Diverted
- 0%
- Flights flown
- 344
- Months covered
- 12
Same route, other flights
Keep nerding
Based on 348 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.