Carrier route record
YXDTW→SDF
Republic Airways · Detroit to Louisville
- Flights
- 408
- Period
- September 2025 to August 2026
- Share of route
- 37%
- Carriers
- 3
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Republic Airways.
Republic on DTW to SDF lands a B, level with the national rate of 77.3%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That rests on 408 flights, with a median arrival 8 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate Republic on DTW to SDF from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
77.6%
Arrivals under 15 minutes late, of 402 completed flights
Avg delay
90 min
Across delayed arrivals only, not all flights
Cancelled
1.23%
National rate is 1.89%
Whole route
77.5%
Every carrier on DTW to SDF, 1,089 flights
These figures cover 408 flights between September 2025 and August 2026. Beyond the headline rate, 9.7% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Republic against every carrier on DTW to SDF
Republic flew 408 of the 1,089 flights on DTW to SDF, about 37% of it. Its 77.6% on time is about level with the route as a whole at 77.5%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from SkyWest at 78.0% to Delta at 45.5%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines | 670 | 78.0% | 85 min | 1.64% | B |
| Republic Airways (this page) | 408 | 77.6% | 90 min | 1.23% | B |
| Delta Air Linesthin sample | 11 | 45.5% | 88 min | 0.00% | F+ |
Flight by flight
Republic flight numbers on DTW to SDF
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Departure window
When Republic runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 19 points, against half a point between the best and worst carrier.
- 5am–8am—
- 8am–11am4 flights—
- 11am–2pm—
- 2pm–5pm39 flights94.9%
- 5pm–8pm154 flights75.5%
- 8pm–5am211 flights76.0%
Scale runs 65% to 100%. Rows with fewer than 30 flights show a dash.
The best window here is not the first bank but the 2pm–5pm slot at 94.9% on time, ahead of 5pm–8pm at 75.5%. Where the curve peaks mid-day rather than at dawn, the constraint is usually congestion at one end rather than the aircraft's own rotation. The 8pm–5am window is the busiest, with 211 flights scheduled in it.
Across the year
Republic on DTW to SDF through the year
August is the worst month at 50.0% on time, 50 points below September, the best at 100.0%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. October was the busiest month here, with 48 flights.
Across the week, Thursday is the strongest day at 83.9% on time and Sunday the weakest at 66.7%, a spread of 17 points.
Arrival by arrival
How late Republic on DTW to SDF runs when it is late
Republic on DTW to SDF often beats the schedule: 104 of 402 completed flights, 26%, arrived 15 minutes or more early. The 90 late arrivals split 21 under half an hour, 30 between 30 and 60 minutes, and 39 an hour or more.
- 15+ min early104 flights25.9%
- Within 15 min208 flights51.7%
- 15–29 min late21 flights5.2%
- 30–59 min late30 flights7.5%
- 1–2 hours late19 flights4.7%
- 2+ hours late20 flights5.0%
Scale runs 0% to 100%.
Share of 402 completed flights by arrival against schedule.
Time lost at the gate mostly stays lost. Of 85 departures that left 15 minutes late or more, only 10 made it up before arrival. 15 flights left on time and still arrived late.
The worst days
Worst days for Republic on DTW to SDF
The latest arrival of the period was on 28 January 2026, 14 hours 32 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. Three of the five worst days fell in January 2026.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 28 January 2026 | 14 hours 32 minutes | Late-arriving aircraft |
| 4 November 2025 | 13 hours 31 minutes | Extreme weather |
| 14 December 2025 | 4 hours 32 minutes | Late-arriving aircraft |
| 14 January 2026 | 3 hours 56 minutes | Late-arriving aircraft |
| 29 January 2026 | 3 hours 51 minutes | Carrier |
Delay causes
Why Republic runs late on this route
Late-arriving aircraft accounts for 49% of the 8,096 delay minutes carriers reported here, and the remaining four split what is left.
- 49%Late-arriving aircraft
- 31%Carrier
- 11%Extreme weather
- 9%National Airspace System
Extreme weather accounts for 11% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 1.9 times the usual weather exposure. The split is drawn from 8,096 reported delay minutes.
49% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 8,096 reported delay minutes here, that single category outweighs weather by 4 to one.
Cancellations sit at 1.23% against a national 1.89%, which is ordinary. Diversions add another 0.25%.
Connections and stage length
What a delay here costs
9.7% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
At 306 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 2pm–5pm window matters as much as it does.
The return leg is a different operation and performs like one: it runs 89.9% on time across 408 flights, 12 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 12 points of difference.
One caution: this is a thin sample. 408 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking Republic on DTW to SDF
Put together: treat all of this as provisional. 408 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 77.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 402 completed flights over 12 months sit behind that.
Related
Where to go next
- DTW to SDF, every carrier
- Republic on SDF to DTW, the return leg
- SkyWest Airlines on DTW to SDF78.0%
- Republic Airways network-wide record
- Detroit Metropolitan Wayne County (DTW) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.