Flight number record

OO 5234

SkyWest Airlines · Chicago to Milwaukee

Route: ORD → MKE
Departs: 10:20
Flights: 289
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 5234, 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 5234 sits in the middle of the pack with a C−. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 289 flights, with a median arrival 9 minutes early.

On time

74.0%

Arrivals under 15 minutes late, of 277 completed flights

Avg delay

72 min

Across delayed arrivals only, not all flights

Cancelled

4.15%

National rate is 1.81%

1 hour+ late

10.5%

National rate is 8.1%

These figures cover 289 flights between July 2025 and June 2026. Beyond the headline rate, 10.5% 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.

Schedule

When OO 5234 flies

OO 5234 flies ORD to MKE without a single fixed slot. Its most common scheduled departure was 10:20, used on 57 of 289 flights, with 10:35 (49 flights) and 11:30 (45 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 10:2057 flights19.7%
Departs 10:3549 flights17.0%
Departs 11:3045 flights15.6%

Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.

Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.

A 10:20 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and OO 5234 runs 10 points worse at 74.0%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

Against the route

OO 5234 next to ORD to MKE

Every carrier on ORD to MKE combined arrived on time 64.1% of the time across 5,201 flights, so OO 5234 is 10 points ahead of it. SkyWest flew 4,933 flights on the same city pair under all its flight numbers, including this one, and those ran 63.7% on time. Across its whole network SkyWest Airlines managed 79.0%, which this flight trails by 5 points.

OO 5234 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 5234thin sample	289	74.0%	72 min	4.15%	C−
All SkyWest Airlines on ORD–MKE	4,933	63.7%	93 min	4.64%	D−
All carriers on ORD–MKE	5,201	64.1%	93 min	4.75%	D−
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 5234 quarter by quarter

OO 5234 did not run the same all year. Its best quarter was Oct–Dec 2025 at 79.8% on time and its weakest Jan–Mar 2026 at 63.0%, a swing of 17 points on roughly 96 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 202592 flights76.9%
Oct–Dec 202590 flights79.8%
Jan–Mar 202686 flights63.0%
Apr–Jun 202621 flights—

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

By weekday, OO 5234 did best on Tuesday at 82.9% on time and worst on Monday at 69.2%. Each day rests on about 41 flights, so a gap of 14 points is worth noticing but could still narrow in another year.

Delay causes

Why OO 5234 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 5,178 reported delay minutes.

Carrier
32%
National Airspace System
31%
Late-arriving aircraft
25%
Extreme weather
11%

Extreme weather accounts for 11% 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 1.8 times the usual weather exposure. The split is drawn from 5,178 delay minutes reported on OO 5234.

Cancellations run at 4.15%, against 1.81% nationally. That is about one flight in 25 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

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.5% 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.

The same number turns up on seven other city pairs in the data, including GRB to ORD (32), SDF to ORD (24) and FWA to ORD (20), but none flew often enough under OO 5234 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. 289 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 5234

For a booking, the cancellation rate is the figure to plan around on OO 5234: 4.15% of its 289 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.

Where to go next

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, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures