Flight number record
OO 4711
SkyWest Airlines · Chicago to Milwaukee
- Route
- ORD → MKE
- Departs
- 19:45
- Flights
- 257
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 4711, 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 4711 draws a C−. About one flight in three arrives at least 15 minutes late, and the typical late arrival is a little over an hour behind schedule. Build slack into anything you connect to. That rests on 257 flights, with a median arrival 1 minute late.
The national on-time rate over the same period is 77.3%, so OO 4711 runs 11 points behind the country as a whole. Across a thousand flights that is about 110 extra late arrivals.
Key figures
On time
66.3%
Arrivals under 15 minutes late, of 243 completed flights
Avg delay
80 min
Across delayed arrivals only, not all flights
Cancelled
5.45%
National rate is 1.89%
1 hour+ late
16.0%
National rate is 8.3%
These figures cover 257 flights between September 2025 and August 2026. Beyond the headline rate, 16.0% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Schedule
When OO 4711 flies
OO 4711 flies ORD to MKE without a single fixed slot. Its most common scheduled departure was 19:45, used on 97 of 257 flights, with 19:50 (77 flights) and 19:42 (38 flights) next.
- Departs 19:4597 flights37.7%
- Departs 19:5077 flights30.0%
- Departs 19:4238 flights14.8%
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 19:45 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.0%, and OO 4711 runs level with that at 66.3%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
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Against the route
OO 4711 next to ORD to MKE
Every carrier on ORD to MKE combined arrived on time 64.3% of the time across 5,344 flights, so OO 4711 is 2 points ahead of it. SkyWest flew 5,047 flights on the same city pair under all its flight numbers, including this one, and those ran 63.9% on time. Across its whole network SkyWest Airlines managed 78.7%, which this flight trails by 12 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| OO 4711thin sample | 257 | 66.3% | 80 min | 5.45% | C− |
| All SkyWest Airlines on ORD–MKE | 5,047 | 63.9% | 92 min | 4.58% | D− |
| All carriers on ORD–MKE | 5,344 | 64.3% | 92 min | 4.68% | D− |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 4711 quarter by quarter
Quarter by quarter OO 4711 held fairly steady: 68.2% in Jan–Mar 2026, 68.2% in Apr–Jun 2026 and 62.7% in Jul–Sep 2026. A spread of 6 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.
- Oct–Dec 202514 flights—
- Jan–Mar 202690 flights68.2%
- Apr–Jun 202691 flights68.2%
- Jul–Sep 202662 flights62.7%
Scale runs 55% to 75%. Rows with fewer than 30 flights show a dash.
By weekday, OO 4711 did best on Saturday at 80.0% on time and worst on Sunday at 47.1%. Each day rests on about 37 flights, so a gap of 33 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late OO 4711 runs when it is late
The 82 late arrivals split 23 under half an hour, 20 between 30 and 60 minutes, and 39 an hour or more.
- 15+ min early58 flights23.9%
- Within 15 min103 flights42.4%
- 15–29 min late23 flights9.5%
- 30–59 min late20 flights8.2%
- 1–2 hours late20 flights8.2%
- 2+ hours late19 flights7.8%
Scale runs 0% to 100%.
Share of 243 completed flights by arrival against schedule.
Time lost at the gate mostly stays lost. Of 66 departures that left 15 minutes late or more, only 4 made it up before arrival. In the other direction, 20 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 MKE.
The worst days
Worst days for OO 4711
The latest arrival of the period was on 2 July 2026, 11 hours 28 minutes behind schedule; most of its delay minutes were filed as extreme weather. The same cause led on three of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 2 July 2026 | 11 hours 28 minutes | Extreme weather |
| 31 August 2026 | 4 hours 5 minutes | Extreme weather |
| 9 July 2026 | 3 hours 51 minutes | Late-arriving aircraft |
| 8 June 2026 | 3 hours 50 minutes | Extreme weather |
| 30 January 2026 | 3 hours 4 minutes | Late-arriving aircraft |
Delay causes
Why OO 4711 runs late
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 6,556 reported delay minutes.
- 33%Late-arriving aircraft
- 24%National Airspace System
- 23%Carrier
- 20%Extreme weather
Extreme weather accounts for 20% 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 quarterly figures above are the more useful view of the risk. The national share is 6%, so this operation carries roughly 3.4 times the usual weather exposure. The split is drawn from 6,556 delay minutes reported on OO 4711.
Cancellations run at 5.45%, against 1.89% nationally. That is roughly 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
16.0% 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 four other city pairs in the data, including COS to DEN (82), OKC to IAH (1) and HDN to DEN (1), but none flew often enough under OO 4711 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to ORD to MKE only.
One caution: this is a thin sample. 257 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 4711
For a booking, the cancellation rate is the figure to plan around on OO 4711: 5.45% of its 257 scheduled flights did not operate. A late arrival costs a little over an hour, but a cancellation costs the day, so leave a later option open.
Related
Where to go next
- ORD to MKE, every carrier and departure
- MKE to ORD, the return direction
- SkyWest Airlines 5555 on the same route52.2%
- SkyWest Airlines 5362 on the same route69.9%
- Chicago O'Hare International (ORD) delay statistics
- Milwaukee Mitchell International (MKE) 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.