Flight number record

OO 5634

SkyWest Airlines · Colorado Springs to Denver

Route: COS → DEN
Departs: 09:30
Flights: 348
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 5634, 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 5634 lands a B+, 6 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 348 flights, with a median arrival 5 minutes early.

Set against the rest of the country, OO 5634's record is 6 points better than the US average of 77.6%. That gap is worth roughly 56 fewer late arrivals for every thousand flights.

On time

83.2%

Arrivals under 15 minutes late, of 346 completed flights

Avg delay

73 min

Across delayed arrivals only, not all flights

Cancelled

0.57%

National rate is 1.81%

1 hour+ late

5.8%

National rate is 8.1%

These figures cover 348 flights between July 2025 and June 2026. The median arrival is 5 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.

Schedule

When OO 5634 flies

OO 5634 flies COS to DEN without a single fixed slot. Its most common scheduled departure was 09:30, used on 157 of 348 flights, with 09:34 (49 flights) and 09:20 (41 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 09:30157 flights45.1%
Departs 09:3449 flights14.1%
Departs 09:2041 flights11.8%

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 09:30 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and OO 5634 runs level with that at 83.2%. 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 5634 next to COS to DEN

Every carrier on COS to DEN combined arrived on time 78.8% of the time across 5,038 flights, so OO 5634 is 4 points ahead of it. SkyWest flew 3,282 flights on the same city pair under all its flight numbers, including this one, and those ran 81.3% on time. Across its whole network SkyWest Airlines managed 79.0%, which this flight beats by 4 points.

OO 5634 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 5634thin sample	348	83.2%	73 min	0.57%	B+
All SkyWest Airlines on COS–DEN	3,282	81.3%	75 min	1.68%	B
All carriers on COS–DEN	5,038	78.8%	71 min	1.33%	B
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 5634 quarter by quarter

Quarter by quarter OO 5634 held fairly steady: 82.4% in Jul–Sep 2025, 82.7% in Oct–Dec 2025, 82.2% in Jan–Mar 2026 and 85.6% in Apr–Jun 2026. A spread of 3 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights82.4%
Oct–Dec 202575 flights82.7%
Jan–Mar 202690 flights82.2%
Apr–Jun 202691 flights85.6%

Scale runs 75% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, OO 5634 did best on Wednesday at 89.6% on time and worst on Thursday at 73.5%. Each day rests on about 50 flights, so a gap of 16 points is worth noticing but could still narrow in another year.

Delay causes

Why OO 5634 runs late

One category carries most of the weight here. Carrier accounts for 55% of the 4,248 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
55%
Extreme weather
21%
National Airspace System
13%
Late-arriving aircraft
11%

Extreme weather accounts for 21% 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 4,248 delay minutes reported on OO 5634.

Cancellations are rare at 0.57%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

Connections and routes

What a delay on this flight costs

5.8% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.

Every one of the 348 flights under OO 5634 in the data flew COS 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. 348 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 5634

For a booking, read OO 5634 as 83.2% on time with 0.57% cancelled over 348 flights. Those are rates from the past twelve months, not a forecast for any particular day.

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