Flight number record
OO 4011
SkyWest Airlines · Atlanta to Aspen
- Route
- ATL → ASE
- Departs
- 09:40
- Flights
- 336
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 4011, 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 4011 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 336 flights, with a median arrival 3 minutes early.
Key figures
On time
76.3%
Arrivals under 15 minutes late, of 316 completed flights
Avg delay
72 min
Across delayed arrivals only, not all flights
Cancelled
1.49%
National rate is 1.89%
1 hour+ late
7.9%
National rate is 8.3%
These figures cover 336 flights between September 2025 and August 2026. The median arrival is 3 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 4011 flies
OO 4011 flies ATL to ASE without a single fixed slot. Its most common scheduled departure was 09:40, used on 165 of 336 flights, with 09:45 (135 flights) next.
- Departs 09:40165 flights49.1%
- Departs 09:45135 flights40.2%
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 09:40 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 83.9%, and OO 4011 runs 8 points worse at 76.3%. 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 4011 next to ATL to ASE
Every carrier on ATL to ASE combined arrived on time 73.2% of the time across 450 flights, so OO 4011 is 3 points ahead of it. 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 4011thin sample | 336 | 76.3% | 72 min | 1.49% | B |
| All SkyWest Airlines on ATL–ASE | 450 | 73.2% | 79 min | 1.56% | C |
| All carriers on ATL–ASE | 450 | 73.2% | 79 min | 1.56% | C |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 4011 quarter by quarter
OO 4011 did not run the same all year. Its best quarter was Jul–Sep 2025 at 86.7% on time and its weakest Jan–Mar 2026 at 68.3%, a swing of 18 points on roughly 67 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 flights86.7%
- Oct–Dec 202592 flights73.3%
- Jan–Mar 202690 flights68.3%
- Apr–Jun 202662 flights82.5%
- Jul–Sep 202662 flights80.3%
Scale runs 60% to 90%.
By weekday, OO 4011 ranged from 71.7% on Monday to 83.0% on Wednesday. With about 48 flights behind each day, a spread of 11 points is inside normal variation, so the day you fly is not worth changing for this flight.
Arrival by arrival
How late OO 4011 runs when it is late
OO 4011 often beats the schedule: 82 of 316 completed flights, 26%, arrived 15 minutes or more early. The 75 late arrivals split 34 under half an hour, 16 between 30 and 60 minutes, and 25 an hour or more.
- 15+ min early82 flights25.9%
- Within 15 min159 flights50.3%
- 15–29 min late34 flights10.8%
- 30–59 min late16 flights5.1%
- 1–2 hours late15 flights4.7%
- 2+ hours late10 flights3.2%
Scale runs 0% to 100%.
Share of 316 completed flights by arrival against schedule.
9 of 53 late departures made up the time and arrived on time, 17% of them. In the other direction, 31 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at ASE.
The worst days
Worst days for OO 4011
The latest arrival of the period was on 1 December 2025, 9 hours 21 minutes behind schedule; most of its delay minutes were filed as extreme weather. The same cause led on three of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 1 December 2025 | 9 hours 21 minutes | Extreme weather |
| 7 December 2025 | 6 hours 35 minutes | Extreme weather |
| 23 February 2026 | 6 hours 9 minutes | Carrier |
| 9 November 2025 | 4 hours 4 minutes | Carrier |
| 5 January 2026 | 3 hours 22 minutes | Extreme weather |
Delay causes
Why OO 4011 runs late
Carrier accounts for 51% of the 5,360 delay minutes carriers reported here, and the remaining four split what is left.
- 51%Carrier
- 32%Extreme weather
- 17%National Airspace System
- 0%Security
Extreme weather accounts for 32% 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 5.3 times the usual weather exposure. The split is drawn from 5,360 delay minutes reported on OO 4011.
Cancellations sit at 1.49% against a national 1.89%, which is ordinary. Diversions add another 4.46%.
Connections and routes
What a delay on this flight costs
7.9% of arrivals land an hour or more late, close to the national 8.3%, so 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.
The 1,304 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.
Every one of the 336 flights under OO 4011 in the data flew ATL to ASE. 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. 336 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 4011
For a booking, read OO 4011 as 76.3% on time with 1.49% cancelled over 336 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- Hartsfield-Jackson Atlanta International (ATL) 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
- Late aircraft, weather, or the airline: what actually causes US flight delays
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.