Flight number record
OO 4650
SkyWest Airlines · Denver to Colorado Springs
- Route
- DEN → COS
- Departs
- 21:05
- Flights
- 322
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 4650, 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 4650 lands a B, about a point worse than the national rate of 77.3%. About one flight in four arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That rests on 322 flights, with a median arrival 6 minutes early.
Key figures
On time
76.3%
Arrivals under 15 minutes late, of 317 completed flights
Avg delay
73 min
Across delayed arrivals only, not all flights
Cancelled
1.24%
National rate is 1.89%
1 hour+ late
9.5%
National rate is 8.3%
These figures cover 322 flights between September 2025 and August 2026. Beyond the headline rate, 9.5% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Schedule
When OO 4650 flies
OO 4650 flies DEN to COS without a single fixed slot. Its most common scheduled departure was 21:05, used on 116 of 322 flights, with 21:10 (81 flights) and 21:00 (74 flights) next.
- Departs 21:05116 flights36.0%
- Departs 21:1081 flights25.2%
- Departs 21:0074 flights23.0%
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 21:05 departure sits in the 8pm–5am window. Across every US flight scheduled in that window the on-time rate is 70.1%, and OO 4650 runs 6 points better at 76.3%. 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 4650 next to DEN to COS
Every carrier on DEN to COS combined arrived on time 76.5% of the time across 4,989 flights, so OO 4650 is about level with it. SkyWest flew 3,338 flights on the same city pair under all its flight numbers, including this one, and those ran 76.6% on time. Across its whole network SkyWest Airlines managed 78.7%, which this flight trails by 2 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| OO 4650thin sample | 322 | 76.3% | 73 min | 1.24% | B |
| All SkyWest Airlines on DEN–COS | 3,338 | 76.6% | 73 min | 1.65% | B |
| All carriers on DEN–COS | 4,989 | 76.5% | 68 min | 1.26% | B |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 4650 quarter by quarter
OO 4650 did not run the same all year. Its best quarter was Jan–Mar 2026 at 84.1% on time and its weakest Jul–Sep 2026 at 66.7%, a swing of 17 points on roughly 81 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 202526 flights—
- Oct–Dec 202554 flights81.1%
- Jan–Mar 202690 flights84.1%
- Apr–Jun 202691 flights77.8%
- Jul–Sep 202661 flights66.7%
Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.
By weekday, OO 4650 did best on Tuesday at 88.1% on time and worst on Sunday at 65.2%. Each day rests on about 46 flights, so a gap of 23 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late OO 4650 runs when it is late
OO 4650 often beats the schedule: 96 of 317 completed flights, 30%, arrived 15 minutes or more early. The 75 late arrivals split 25 under half an hour, 20 between 30 and 60 minutes, and 30 an hour or more.
- 15+ min early96 flights30.3%
- Within 15 min146 flights46.1%
- 15–29 min late25 flights7.9%
- 30–59 min late20 flights6.3%
- 1–2 hours late18 flights5.7%
- 2+ hours late12 flights3.8%
Scale runs 0% to 100%.
Share of 317 completed flights by arrival against schedule.
17 of 85 late departures made up the time and arrived on time, 20% of them. 7 flights left on time and still arrived late.
The worst days
Worst days for OO 4650
The latest arrival of the period was on 3 December 2025, 13 hours 21 minutes behind schedule; most of its delay minutes were filed as national airspace system delay. On three of the five worst days the largest share was filed as a late-arriving aircraft.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 3 December 2025 | 13 hours 21 minutes | National Airspace System |
| 13 August 2026 | 4 hours | National Airspace System |
| 31 May 2026 | 3 hours 49 minutes | Late-arriving aircraft |
| 21 August 2026 | 3 hours 12 minutes | Late-arriving aircraft |
| 4 May 2026 | 3 hours 10 minutes | Late-arriving aircraft |
Delay causes
Why OO 4650 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 5,504 reported delay minutes.
- 42%National Airspace System
- 28%Carrier
- 21%Late-arriving aircraft
- 9%Extreme weather
42% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 2,301 minutes out of 5,504, against a national NAS share of 21%. The split is drawn from 5,504 delay minutes reported on OO 4650.
Cancellations sit at 1.24% against a national 1.89%, which is ordinary. Diversions add another 0.31%.
Connections and routes
What a delay on this flight costs
9.5% 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 three other city pairs in the data, including BIS to DEN (58), FAT to LAX (37) and FAT to SFO (1), but none flew often enough under OO 4650 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to DEN to COS only.
One caution: this is a thin sample. 322 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 4650
For a booking, read OO 4650 as 76.3% on time with 1.24% cancelled over 322 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- DEN to COS, every carrier and departure
- COS to DEN, the return direction
- SkyWest Airlines 5546 on the same route80.6%
- SkyWest Airlines 5246 on the same route84.3%
- SkyWest Airlines 5861 on the same route66.5%
- SkyWest Airlines 5306 on the same route83.6%
- Denver International (DEN) 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
- How often a connection fails at the major US hubs
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.