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DelayAtlas

Flight number record

OO 4778

SkyWest Airlines · Chicago to Fargo

Route
ORD → FAR
Departs
08:45
Flights
321
Period
July 2025 to June 2026
DGRADE

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 4778, 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 4778 draws a D. About one flight in three arrives at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 321 flights, with a median arrival 2 minutes late.

The national on-time rate over the same period is 77.6%, so OO 4778 runs 13 points behind the country as a whole. Across a thousand flights that is about 129 extra late arrivals.

Key figures

On time

64.7%

Arrivals under 15 minutes late, of 312 completed flights

Avg delay

63 min

Across delayed arrivals only, not all flights

Cancelled

2.18%

National rate is 1.81%

1 hour+ late

10.9%

National rate is 8.1%

These figures cover 321 flights between July 2025 and June 2026. Beyond the headline rate, 10.9% 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 4778 flies

OO 4778 is scheduled to leave Chicago (ORD) at 08:45 local time and reach Fargo (FAR) at 10:56. That slot held for 302 of the 321 scheduled departures in the data, so the figures below describe one steady operation rather than a number that moved around the clock.

  • Departs 08:45302 flights94.1%

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 08:45 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and OO 4778 runs 19 points worse at 64.7%. 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 4778 next to ORD to FAR

Every carrier on ORD to FAR combined arrived on time 69.5% of the time across 2,065 flights, so OO 4778 is 5 points behind it. SkyWest flew 1,005 flights on the same city pair under all its flight numbers, including this one, and those ran 62.6% on time. Across its whole network SkyWest Airlines managed 79.0%, which this flight trails by 14 points.

OO 4778 against its route and carrier
Compared withFlightsOn timeAvg delayCancelledGrade
OO 4778thin sample32164.7%63 min2.18%D
All SkyWest Airlines on ORD–FAR1,00562.6%85 min3.18%D−
All carriers on ORD–FAR2,06569.5%76 min2.91%C
SkyWest Airlines, whole network852,93579.0%88 min1.77%B

Across the year

OO 4778 quarter by quarter

OO 4778 did not run the same all year. Its best quarter was Apr–Jun 2026 at 70.2% on time and its weakest Oct–Dec 2025 at 58.9%, a swing of 11 points on roughly 80 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 flights68.9%
  • Oct–Dec 202592 flights58.9%
  • Jan–Mar 202688 flights63.5%
  • Apr–Jun 202649 flights70.2%

Scale runs 50% to 75%. Rows with fewer than 30 flights show a dash.

By weekday, OO 4778 ranged from 58.7% on Friday to 68.2% on Thursday. With about 46 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.

On-time rate by day of the week66.7Mon63.0Tue65.2Wed68.2Thu58.7Fri65.1Sat66.7Sun
Monday: 66.7 percent on time. Tuesday: 63.0 percent on time. Wednesday: 65.2 percent on time. Thursday: 68.2 percent on time. Friday: 58.7 percent on time. Saturday: 65.1 percent on time. Sunday: 66.7 percent on time

Delay causes

Why OO 4778 runs late

One category carries most of the weight here. Carrier accounts for 50% of the 6,937 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
    50%
  • National Airspace System
    24%
  • Late-arriving aircraft
    23%
  • Extreme weather
    2%

The largest share of delay minutes, 50%, 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 3,467 of the 6,937 delay minutes reported here. The split is drawn from 6,937 delay minutes reported on OO 4778.

Cancellations sit at 2.18% against a national 1.81%, which is ordinary. Diversions add another 0.62%.

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. 10.9% 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 557 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The same number turns up on two other city pairs in the data, including FAR to ORD (41) and ORD to MSN (10), but none flew often enough under OO 4778 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to ORD to FAR only.

One caution: this is a thin sample. 321 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 4778

For a booking, read OO 4778 as 64.7% on time with 2.18% cancelled over 321 flights. Those are rates from the past twelve months, not a forecast for any particular day.

Related

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.