Carrier route record

OODTW→SDF

SkyWest Airlines · Detroit to Louisville

Flights: 753
Period: July 2025 to June 2026
Share of route: 63%
Carriers: 4

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with SkyWest Airlines.

SkyWest on DTW to SDF lands a B, 2 points worse than the national rate of 77.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 753 flights, with a median arrival 6 minutes early.

The US average over the same twelve months is 77.6%, so there is little to separate SkyWest on DTW to SDF from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

76.0%

Arrivals under 15 minutes late, of 742 completed flights

Avg delay

79 min

Across delayed arrivals only, not all flights

Cancelled

1.46%

National rate is 1.81%

Whole route

77.2%

Every carrier on DTW to SDF, 1,190 flights

These figures cover 753 flights between July 2025 and June 2026. Beyond the headline rate, 10.1% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.

Carrier by carrier

SkyWest against every carrier on DTW to SDF

SkyWest flew 753 of the 1,190 flights on DTW to SDF, most of the route. Its 76.0% on time is about level with the route as a whole at 77.2%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from Spirit at 83.3% to Delta at 45.5%. 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.

On-time performance by carrier on DTW to SDF
Airline	Flights	On time	Avg delay	Cancelled	Grade
Spirit Airlinesthin sample	18	83.3%	39 min	0.00%	B+
Republic Airways	408	80.0%	94 min	0.74%	B+
SkyWest Airlines (this page)	753	76.0%	79 min	1.46%	B
Delta Air Linesthin sample	11	45.5%	88 min	0.00%	F+

Departure window

When SkyWest runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 18 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am344 flights81.1%
11am–2pm210 flights79.3%
2pm–5pm137 flights63.4%
5pm–8pm62 flights63.9%
8pm–5am—

Scale runs 55% to 85%. Rows with fewer than 30 flights show a dash.

Book the morning departure. Flights leaving between 8am–11am arrive on time 81.1% of the time, against 63.4% for the afternoon window. That is 18 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 344 flights scheduled in it.

Across the year

SkyWest on DTW to SDF through the year

Darker means more delays. Figures are on-time percentages.September best, December worst

December is the weak month at 57.4% on time, against 93.0% in September. 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. April was the busiest month here, with 86 flights.

Across the week, Saturday is the strongest day at 85.1% on time and Friday the weakest at 67.6%. 18 points is a smaller lever than departure hour, but it is free.

Delay causes

Why SkyWest runs late on this route

One category carries most of the weight here. Carrier accounts for 70% of the 14,000 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.

Carrier
70%
Extreme weather
21%
National Airspace System
9%

Extreme weather accounts for 21% 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 3.3 times the usual weather exposure. The split is drawn from 13,991 reported delay minutes.

The largest share of delay minutes, 70%, 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 9,796 of the 14,000 delay minutes reported here.

Cancellations sit at 1.46% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.1% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum 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 8am–11am window matters as much as it does.

The return leg runs 77.7% on time across 753 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

One caution: this is a thin sample. 753 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 SkyWest on DTW to SDF

Put together: treat all of this as provisional. 753 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 76.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 742 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures