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DelayAtlas

Flight number record

OO 3940

SkyWest Airlines · Colorado Springs to Salt Lake City

Route
COS → SLC
Departs
08:15
Flights
365
Period
July 2025 to June 2026
A+GRADE

Historical statistics for July 2025 to June 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 19 points better than the national rate of 77.6%. 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 19 points better than the US average of 77.6%. That gap is worth roughly 188 fewer late arrivals for every thousand flights.

Key figures

On time

96.4%

Arrivals under 15 minutes late, of 365 completed flights

Avg delay

100 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

1 hour+ late

0.8%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 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.

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 133 of 365 flights, with 07:59 (62 flights) and 08:00 (54 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

  • Departs 08:15133 flights36.4%
  • Departs 07:5962 flights17.0%
  • Departs 08:0054 flights14.8%

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 08:15 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and OO 3940 runs 12 points better at 96.4%. 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 3940 next to COS to SLC

Every carrier on COS to SLC combined arrived on time 93.1% of the time across 716 flights, so OO 3940 is 3 points ahead of it. Across its whole network SkyWest Airlines managed 79.0%, which this flight beats by 17 points.

OO 3940 against its route and carrier
Compared withFlightsOn timeAvg delayCancelledGrade
OO 394036596.4%100 min0.00%A+
All SkyWest Airlines on COS–SLC71693.1%63 min0.14%A+
All carriers on COS–SLC71693.1%63 min0.14%A+
SkyWest Airlines, whole network852,93579.0%88 min1.77%B

Across the year

OO 3940 quarter by quarter

Quarter by quarter OO 3940 held fairly steady: 95.7% in Jul–Sep 2025, 97.8% in Oct–Dec 2025, 94.4% in Jan–Mar 2026 and 97.8% 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 flights95.7%
  • Oct–Dec 202592 flights97.8%
  • Jan–Mar 202690 flights94.4%
  • Apr–Jun 202691 flights97.8%

Scale runs 85% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, OO 3940 ranged from 92.3% on Sunday to 98.1% on Monday. With about 52 flights behind each day, a spread of 6 points is inside normal variation, so the day you fly is not worth changing for this flight.

On-time rate by day of the week98.1Mon98.1Tue96.2Wed96.2Thu96.2Fri98.1Sat92.3Sun
Monday: 98.1 percent on time. Tuesday: 98.1 percent on time. Wednesday: 96.2 percent on time. Thursday: 96.2 percent on time. Friday: 96.2 percent on time. Saturday: 98.1 percent on time. Sunday: 92.3 percent on time

Delay causes

Why OO 3940 runs late

One category carries most of the weight here. Extreme weather accounts for 72% of the 1,300 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.

  • Extreme weather
    72%
  • Carrier
    27%
  • National Airspace System
    1%

Extreme weather accounts for 72% 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 11.6 times the usual weather exposure. The split is drawn from 1,300 delay minutes reported on OO 3940.

Cancellations are rare at 0.00%, below the national 1.81% 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 0.8% land an hour or more behind schedule, against 8.1% 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: 96.4% on time and 0.00% cancelled. That is a base rate, not a promise about any single 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.