Route Reliability
Washington → Louisville
IAD–SDF · 451 miles · Washington Dulles International Airport to Louisville Muhammad Ali International Airport
- 82%
- Arrive within 15 minutes
- 9 min
- Average arrival delay
- 0.8%
- Cancelled
- 916
- Flights in the data
Data through May 2026.
United Airlines is the only airline in this data on this route, arriving on time 82% of the time across 916 flights. No comparison to make.
What the data says
The 12–3 PM departure wins.
IAD–SDF flights departing between 12–3 PM arrived on time 83% of the time, versus 74% between 6–9 PM.
Mondays have been rough.
IAD–SDF flights arrived on time 88% of the time on Saturdays and just 73% on Mondays. That gap is worth planning around.
Trending in the right direction.
IAD–SDF flights arrived on time 87% of the time over the last three months in the data, compared with 78% in the three months before that.
Best historical flights
Ranked by on-time arrivals, minimum 100 flights. Past performance, not a promise.
Top flights by on-time rate
More flights on this route
The breakdown
- Mon73%(131 flights)
- Tue88%(128 flights)
- Wed81%(132 flights)
- Thu80%(130 flights)
- Fri80%(132 flights)
- Sat88%(120 flights)
- Sun82%(133 flights)
- 6–9 AM80%(89 flights)
- 12–3 PM83%(359 flights)
- 3–6 PM83%(324 flights)
- 6–9 PM74%(113 flights)
- 9 PM–12 AM76%(21 flights)
Jun 65% → May 83% on time
| Month | On-time percentage | Flights |
|---|---|---|
| June 2025 | 65% | 88 |
| July 2025 | 74% | 119 |
| August 2025 | 92% | 107 |
| September 2025 | 89% | 84 |
| October 2025 | 84% | 62 |
| November 2025 | 83% | 59 |
| December 2025 | 74% | 61 |
| January 2026 | 71% | 58 |
| February 2026 | 91% | 53 |
| March 2026 | 84% | 62 |
| April 2026 | 93% | 61 |
| May 2026 | 83% | 92 |
Same trip, other airports
Keep nerding
Based on 916 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.