Carrier route record
YXSDF→DTW
Republic Airways · Louisville to Detroit
- Flights
- 408
- Period
- July 2025 to June 2026
- Share of route
- 34%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Republic Airways.
Republic on SDF to DTW earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 12 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 408 flights, with a median arrival 10 minutes early.
Set against the rest of the country, Republic's SDF to DTW record is 12 points better than the US average of 77.6%. That gap is worth roughly 121 fewer late arrivals for every thousand flights.
Key figures
On time
89.7%
Arrivals under 15 minutes late, of 407 completed flights
Avg delay
66 min
Across delayed arrivals only, not all flights
Cancelled
0.25%
National rate is 1.81%
Whole route
81.9%
Every carrier on SDF to DTW, 1,190 flights
These figures cover 408 flights between July 2025 and June 2026. The median arrival is 10 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
Republic against every carrier on SDF to DTW
Republic flew 408 of the 1,190 flights on SDF to DTW, about 34% of it. Its 89.7% on time is 8 points better than the route as a whole, which runs 81.9%. Ranked by on-time rate it is first of four carriers on the route, where the range runs from Republic at 89.7% to Delta at 63.6%. Two 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 |
|---|---|---|---|---|---|
| Republic Airways (this page) | 408 | 89.7% | 66 min | 0.25% | A+ |
| Spirit Airlinesthin sample | 18 | 88.9% | 306 min | 0.00% | A+ |
| SkyWest Airlines | 753 | 77.7% | 121 min | 1.20% | B |
| Delta Air Linesthin sample | 11 | 63.6% | 114 min | 0.00% | D+ |
Flight by flight
Republic flight numbers on SDF to DTW
Departure window
When Republic runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 408 flights.
- 5am–8am74 flights85.1%
- 8am–11am295 flights90.1%
- 11am–2pm—
- 2pm–5pm—
- 5pm–8pm39 flights94.9%
- 8pm–5am—
Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is the strongest at 94.9% on time. The full set of windows spans 10 points.
Across the year
Republic on SDF to DTW through the year
January is the weak month at 71.9% on time, against 96.8% in August. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. October was the busiest month here, with 48 flights.
Across the week, Thursday is the strongest day at 94.7% on time and Friday the weakest at 83.6%. 11 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Republic runs late on this route
One category carries most of the weight here. Carrier accounts for 64% of the 2,759 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 64%Carrier
- 23%National Airspace System
- 12%Late-arriving aircraft
- 1%Extreme weather
The largest share of delay minutes, 64%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 1,760 of the 2,759 delay minutes reported here. The split is drawn from 2,759 reported delay minutes.
Cancellations are rare at 0.25%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
Badly late arrivals are rare here: only 3.7% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
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 5pm–8pm window matters as much as it does.
The return leg is a different operation and performs like one: it runs 80.0% on time across 408 flights, 10 points below 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 10 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 SDF to DTW
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 89.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 407 completed flights over 12 months sit behind that.
Related
Where to go next
- SDF to DTW, every carrier
- Republic on DTW to SDF, the return leg
- SkyWest Airlines on SDF to DTW77.7%
- Republic Airways network-wide record
- Detroit Metropolitan Wayne County (DTW) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.