Flight number record
OO 3940
SkyWest Airlines · Colorado Springs to Salt Lake City
- Route
- COS → SLC
- Departs
- 08:15
- Flights
- 365
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 3940, 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 3940 earns an A+. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 18 points better than the national rate of 77.3%. When something does go wrong the average delay runs close to two hours. That rests on 365 flights, with a median arrival 15 minutes early.
Set against the rest of the country, OO 3940's record is 18 points better than the US average of 77.3%. That gap is worth roughly 175 fewer late arrivals for every thousand flights.
Key figures
On time
94.8%
Arrivals under 15 minutes late, of 365 completed flights
Avg delay
112 min
Across delayed arrivals only, not all flights
Cancelled
0.00%
National rate is 1.89%
1 hour+ late
1.9%
National rate is 8.3%
These figures cover 365 flights between September 2025 and August 2026. The median arrival is 15 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.
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Schedule
When OO 3940 flies
OO 3940 flies COS to SLC without a single fixed slot. Its most common scheduled departure was 08:15, used on 92 of 365 flights, with 08:10 (89 flights) and 07:59 (62 flights) next.
- Departs 08:1592 flights25.2%
- Departs 08:1089 flights24.4%
- Departs 07:5962 flights17.0%
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 08:15 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 83.9%, and OO 3940 runs 11 points better at 94.8%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
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Against the route
OO 3940 next to COS to SLC
Every carrier on COS to SLC combined arrived on time 91.9% of the time across 721 flights, so OO 3940 is 3 points ahead of it. Across its whole network SkyWest Airlines managed 78.7%, which this flight beats by 16 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| OO 3940 | 365 | 94.8% | 112 min | 0.00% | A+ |
| All SkyWest Airlines on COS–SLC | 721 | 91.9% | 76 min | 0.14% | A+ |
| All carriers on COS–SLC | 721 | 91.9% | 76 min | 0.14% | A+ |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 3940 quarter by quarter
OO 3940 did not run the same all year. Its best quarter was Oct–Dec 2025 at 97.8% on time and its weakest Jul–Sep 2026 at 85.5%, a swing of 12 points on roughly 73 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 202530 flights96.7%
- Oct–Dec 202592 flights97.8%
- Jan–Mar 202690 flights94.4%
- Apr–Jun 202691 flights97.8%
- Jul–Sep 202662 flights85.5%
Scale runs 75% to 100%.
By weekday, OO 3940 did best on Monday at 100.0% on time and worst on Sunday at 86.5%. Each day rests on about 52 flights, so a gap of 14 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late OO 3940 runs when it is late
OO 3940 often beats the schedule: 189 of 365 completed flights, 52%, arrived 15 minutes or more early. The 19 late arrivals split 5 under half an hour, 7 between 30 and 60 minutes, and 7 an hour or more.
- 15+ min early189 flights51.8%
- Within 15 min157 flights43.0%
- 15–29 min late5 flights1.4%
- 30–59 min late7 flights1.9%
- 1–2 hours late4 flights1.1%
- 2+ hours late3 flights0.8%
Scale runs 0% to 100%.
Share of 365 completed flights by arrival against schedule.
Time lost at the gate mostly stays lost. Of 20 departures that left 15 minutes late or more, only 2 made it up before arrival. Only 1 left on time and still arrived late.
The worst days
Worst days for OO 3940
The latest arrival of the period was on 25 March 2026, 13 hours 21 minutes behind schedule; most of its delay minutes were filed as extreme weather. On four of the five worst days the largest share was filed as carrier-caused (crew, maintenance, fuelling, baggage).
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 25 March 2026 | 13 hours 21 minutes | Extreme weather |
| 18 August 2026 | 5 hours 34 minutes | Carrier |
| 29 August 2026 | 3 hours 20 minutes | Carrier |
| 23 July 2026 | 1 hour 49 minutes | Carrier |
| 25 January 2026 | 1 hour 29 minutes | Carrier |
Delay causes
Why OO 3940 runs late
Carrier accounts for 57% of the 2,118 delay minutes carriers reported here, and the remaining four split what is left.
- 57%Carrier
- 43%Extreme weather
- 0%National Airspace System
Extreme weather accounts for 43% 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 7.2 times the usual weather exposure. The split is drawn from 2,118 delay minutes reported on OO 3940.
Cancellations are rare at 0.00%, below the national 1.89% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.
Connections and routes
What a delay on this flight costs
Badly late arrivals are rare here: only 1.9% land an hour or more behind schedule, against 8.3% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
Every one of the 365 flights under OO 3940 in the data flew COS to SLC. 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. 365 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 3940
For a booking, OO 3940 has one of the better records a US domestic flight can show: 94.8% on time and 0.00% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- COS to SLC, every carrier and departure
- SLC to COS, the return direction
- SkyWest Airlines 4449 on the same route88.0%
- Salt Lake City International (SLC) 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
- Worst months to fly in the US, ranked by the data
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.