Carrier route record
OOORD→SDF
SkyWest Airlines · Chicago to Louisville
- Flights
- 645
- Period
- July 2025 to June 2026
- Share of route
- 23%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with SkyWest Airlines.
SkyWest on ORD to SDF sits in the middle of the pack with a C−. About seven flights in ten arrive on time by the DOT's definition, 7 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 645 flights. The strongest carrier on the route with a full sample, Envoy Air, flew 415 at 84.1% on time.
The national on-time rate over the same period is 77.6%, so SkyWest on ORD to SDF runs 7 points behind the country as a whole. Across a thousand flights that is about 66 extra late arrivals.
Key figures
On time
71.0%
Arrivals under 15 minutes late, of 624 completed flights
Avg delay
69 min
Across delayed arrivals only, not all flights
Cancelled
3.10%
National rate is 1.81%
Whole route
75.3%
Every carrier on ORD to SDF, 2,804 flights
These figures cover 645 flights between July 2025 and June 2026. Beyond the headline rate, 11.5% 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 ORD to SDF
SkyWest flew 645 of the 2,804 flights on ORD to SDF, about 23% of it. Its 71.0% on time is 4 points worse than the route as a whole, which runs 75.3%. Ranked by on-time rate it is number three of five carriers on the route, where the range runs from Envoy at 84.1% to United at 33.3%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. Envoy Air arrives on time 84.1% of the time; Republic Airways manages 75.0%. Sample sizes sit next to every figure, because a two-point gap across 1,733 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Envoy Air | 415 | 84.1% | 54 min | 1.20% | B |
| Republic Airways | 1,733 | 75.0% | 75 min | 3.87% | B− |
| SkyWest Airlines (this page) | 645 | 71.0% | 69 min | 3.10% | C− |
| American Airlinesthin sample | 4 | 50.0% | 71 min | 0.00% | F+ |
| United Airlinesthin sample | 6 | 33.3% | 45 min | 0.00% | F+ |
Republic Airways cancels 3.9% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
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 13 points, against 9 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am123 flights79.2%
- 8am–11am165 flights66.0%
- 11am–2pm100 flights72.4%
- 2pm–5pm219 flights69.5%
- 5pm–8pm10 flights—
- 8pm–5am28 flights—
Scale runs 60% to 85%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 79.2% of the time, against 66.0% for the morning window. That is 13 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 219 flights scheduled in it.
Across the year
SkyWest on ORD to SDF through the year
February is the weak month at 60.0% on time, against 87.2% 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 91 flights.
Across the week, Wednesday is the strongest day at 81.4% on time and Friday the weakest at 64.5%. 17 points is a smaller lever than departure hour, but it is free.
Delay causes
Why SkyWest runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 12,000 reported delay minutes.
- 38%Late-arriving aircraft
- 31%Carrier
- 24%National Airspace System
- 8%Extreme weather
38% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 12,000 reported delay minutes here, that single category outweighs weather by 5 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 12,451 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 79.2% on time here.
Cancellations run at 3.10%, against 1.81% nationally. That is about one flight in 30 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
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. 11.5% 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 286 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 5am–8am window matters as much as it does.
The return leg runs 70.9% on time across 645 flights, within half a point 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. 645 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 ORD to SDF
Put together: the delay figures matter less here than the 3.10% cancellation rate. A late arrival costs you a little over an hour; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 624 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to SDF, every carrier
- SkyWest on SDF to ORD, the return leg
- Envoy Air on ORD to SDF84.1%
- Republic Airways on ORD to SDF75.0%
- SkyWest Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- The US routes with the most cancellations
- Why the first flight of the morning is statistically safest
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.