Flight number record

OO 5966

SkyWest Airlines · Arcata/Eureka to Denver

Route: ACV → DEN
Departs: 12:30
Flights: 346
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 5966, 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 5966 lands a B, level with the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by close to two hours on average. That is a workable record, not a spotless one. That rests on 346 flights, with a median arrival 5 minutes early.

On time

78.3%

Arrivals under 15 minutes late, of 337 completed flights

Avg delay

113 min

Across delayed arrivals only, not all flights

Cancelled

1.45%

National rate is 1.81%

1 hour+ late

12.5%

National rate is 8.1%

These figures cover 346 flights between July 2025 and June 2026. Beyond the headline rate, 12.5% 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 5966 flies

OO 5966 flies ACV to DEN without a single fixed slot. Its most common scheduled departure was 12:30, used on 167 of 346 flights, with 12:34 (83 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 12:30167 flights48.3%
Departs 12:3483 flights24.0%

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 12:30 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.8%, and OO 5966 runs level with that at 78.3%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

OO 5966 next to ACV to DEN

Every carrier on ACV to DEN combined arrived on time 78.0% of the time across 378 flights, so OO 5966 is about level with it. Across its whole network SkyWest Airlines managed 79.0%, close to this flight's figure.

OO 5966 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 5966thin sample	346	78.3%	113 min	1.45%	B
All SkyWest Airlines on ACV–DEN	378	78.0%	127 min	1.32%	B
All carriers on ACV–DEN	378	78.0%	127 min	1.32%	B
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 5966 quarter by quarter

OO 5966 did not run the same all year. Its best quarter was Oct–Dec 2025 at 90.1% on time and its weakest Apr–Jun 2026 at 62.8%, a swing of 27 points on roughly 87 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 202574 flights77.5%
Oct–Dec 202591 flights90.1%
Jan–Mar 202690 flights82.0%
Apr–Jun 202691 flights62.8%

Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, OO 5966 did best on Thursday at 85.4% on time and worst on Tuesday at 71.4%. Each day rests on about 49 flights, so a gap of 14 points is worth noticing but could still narrow in another year.

Delay causes

Why OO 5966 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 8,277 reported delay minutes.

Extreme weather
41%
National Airspace System
26%
Late-arriving aircraft
20%
Carrier
13%

Extreme weather accounts for 41% 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 6.6 times the usual weather exposure. The split is drawn from 8,277 delay minutes reported on OO 5966.

Cancellations sit at 1.45% against a national 1.81%, which is ordinary. Diversions add another 1.16%.

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. 12.5% 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 1,026 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.

Every one of the 346 flights under OO 5966 in the data flew ACV to DEN. The number was not reused on any other city pair, which makes this a clean record of one route.

One caution: this is a thin sample. 346 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 5966

For a booking, OO 5966 is a flight to put a long connection behind. 12.5% of its completed flights arrived an hour or more late, which a short layover will not absorb. If the onward flight is on a separate ticket, the risk sits with you.

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