Flight number record
OO 4685
SkyWest Airlines · Duluth to Chicago
- Route
- DLH → ORD
- Departs
- 15:03
- Flights
- 307
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 4685, check with SkyWest Airlines. SkyWest Airlines flies under contract for larger airlines, so a ticket for this flight may show a different airline code and number.
OO 4685 draws a D−. Roughly one flight in two arrives at least 15 minutes late, and the typical late arrival is an hour and a half behind schedule. Build slack into anything you connect to. That rests on 307 flights, with a median arrival 8 minutes late.
The national on-time rate over the same period is 77.3%, so OO 4685 runs 18 points behind the country as a whole. Across a thousand flights that is about 184 extra late arrivals.
Key figures
On time
58.9%
Arrivals under 15 minutes late, of 292 completed flights
Avg delay
95 min
Across delayed arrivals only, not all flights
Cancelled
4.89%
National rate is 1.89%
1 hour+ late
19.2%
National rate is 8.3%
These figures cover 307 flights between September 2025 and August 2026. Beyond the headline rate, 19.2% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Schedule
When OO 4685 flies
OO 4685 flies DLH to ORD without a single fixed slot. Its most common scheduled departure was 15:03, used on 101 of 307 flights, with 15:07 (51 flights) and 15:05 (37 flights) next.
- Departs 15:03101 flights32.9%
- Departs 15:0751 flights16.6%
- Departs 15:0537 flights12.1%
Scale runs 0% to 100%.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 15:03 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 71.9%, and OO 4685 runs 13 points worse at 58.9%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
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Against the route
OO 4685 next to DLH to ORD
Every carrier on DLH to ORD combined arrived on time 69.0% of the time across 1,239 flights, so OO 4685 is 10 points behind it. SkyWest flew 1,116 flights on the same city pair under all its flight numbers, including this one, and those ran 68.3% on time. Across its whole network SkyWest Airlines managed 78.7%, which this flight trails by 20 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| OO 4685thin sample | 307 | 58.9% | 95 min | 4.89% | D− |
| All SkyWest Airlines on DLH–ORD | 1,116 | 68.3% | 108 min | 4.84% | C− |
| All carriers on DLH–ORD | 1,239 | 69.0% | 106 min | 4.76% | C− |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 4685 quarter by quarter
OO 4685 did not run the same all year. Its best quarter was Oct–Dec 2025 at 60.2% on time and its weakest Jul–Sep 2026 at 50.0%, a swing of 10 points on roughly 77 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
- Jul–Sep 202529 flights—
- Oct–Dec 202588 flights60.2%
- Jan–Mar 202687 flights58.5%
- Apr–Jun 202662 flights60.0%
- Jul–Sep 202641 flights50.0%
Scale runs 40% to 65%. Rows with fewer than 30 flights show a dash.
By weekday, OO 4685 ranged from 52.4% on Thursday to 61.9% on Tuesday. With about 44 flights behind each day, a spread of 10 points is inside normal variation, so the day you fly is not worth changing for this flight.
Arrival by arrival
How late OO 4685 runs when it is late
The 120 late arrivals split 39 under half an hour, 25 between 30 and 60 minutes, and 56 an hour or more.
- 15+ min early68 flights23.3%
- Within 15 min104 flights35.6%
- 15–29 min late39 flights13.4%
- 30–59 min late25 flights8.6%
- 1–2 hours late29 flights9.9%
- 2+ hours late27 flights9.2%
Scale runs 0% to 100%.
Share of 292 completed flights by arrival against schedule.
Time lost at the gate mostly stays lost. Of 94 departures that left 15 minutes late or more, only 9 made it up before arrival. In the other direction, 35 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at ORD.
The worst days
Worst days for OO 4685
The latest arrival of the period was on 22 January 2026, 19 hours 36 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. On three of the five worst days the largest share was filed as national airspace system delay.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 22 January 2026 | 19 hours 36 minutes | Late-arriving aircraft |
| 17 March 2026 | 9 hours 15 minutes | Late-arriving aircraft |
| 7 November 2025 | 7 hours 10 minutes | National Airspace System |
| 6 March 2026 | 6 hours 11 minutes | National Airspace System |
| 30 November 2025 | 5 hours 19 minutes | National Airspace System |
Delay causes
Why OO 4685 runs late
Late-arriving aircraft accounts for 53% of the 11,000 delay minutes carriers reported here, and the remaining four split what is left.
- 53%Late-arriving aircraft
- 29%National Airspace System
- 13%Carrier
- 5%Extreme weather
53% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 11,000 reported delay minutes here, that single category outweighs weather by 10 to one. The split is drawn from 11,357 delay minutes reported on OO 4685.
Cancellations run at 4.89%, against 1.89% nationally. That is about one flight in twenty 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 routes
What a delay on this flight costs
19.2% 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.
The same number turns up on five other city pairs in the data, including ATW to ORD (32), DAY to ORD (20) and FSD to ORD (1), but none flew often enough under OO 4685 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to DLH to ORD only.
One caution: this is a thin sample. 307 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 OO 4685
For a booking, the cancellation rate is the figure to plan around on OO 4685: 4.89% of its 307 scheduled flights did not operate. A late arrival costs an hour and a half, but a cancellation costs the day, so leave a later option open.
Related
Where to go next
- DLH to ORD, every carrier and departure
- ORD to DLH, the return direction
- SkyWest Airlines 4670 on the same route77.1%
- SkyWest Airlines 5754 on the same route66.9%
- Chicago O'Hare International (ORD) delay statistics
- SkyWest Airlines on-time record
- Every SkyWest Airlines flight number with a record
- The most and least reliable flight numbers in the US
- Why the first flight of the morning is statistically safest
A flight number here means SkyWest Airlines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.
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.