Flight number record
OO 3439
SkyWest Airlines · San Diego to Sacramento
- Route
- SAN → SMF
- Departs
- 11:00
- Flights
- 267
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 3439, 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 3439 sits in the middle of the pack with a B. Close to three flights in four arrive on time by the DOT's definition, 2 points worse than the national rate of 77.3%. The late ones land roughly 50 minutes behind schedule. That rests on 267 flights, with a median arrival 2 minutes early.
Key figures
On time
75.7%
Arrivals under 15 minutes late, of 263 completed flights
Avg delay
48 min
Across delayed arrivals only, not all flights
Cancelled
1.12%
National rate is 1.89%
1 hour+ late
7.2%
National rate is 8.3%
These figures cover 267 flights between September 2025 and August 2026. The median arrival is 2 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.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Schedule
When OO 3439 flies
OO 3439 flies SAN to SMF without a single fixed slot. Its most common scheduled departure was 11:00, used on 70 of 267 flights, with 12:30 (52 flights) and 13:10 (30 flights) next.
- Departs 11:0070 flights26.2%
- Departs 12:3052 flights19.5%
- Departs 13:1030 flights11.2%
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 11:00 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.3%, and OO 3439 runs 3 points worse at 75.7%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Against the route
OO 3439 next to SAN to SMF
Every carrier on SAN to SMF combined arrived on time 74.5% of the time across 5,181 flights, so OO 3439 is about level with it. SkyWest flew 1,136 flights on the same city pair under all its flight numbers, including this one, and those ran 80.0% on time. Across its whole network SkyWest Airlines managed 78.7%, which this flight trails by 3 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| OO 3439thin sample | 267 | 75.7% | 48 min | 1.12% | B |
| All SkyWest Airlines on SAN–SMF | 1,136 | 80.0% | 49 min | 1.41% | B |
| All carriers on SAN–SMF | 5,181 | 74.5% | 47 min | 0.87% | C+ |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 3439 quarter by quarter
OO 3439 did not run the same all year. Its best quarter was Jan–Mar 2026 at 81.2% on time and its weakest Oct–Dec 2025 at 64.4%, a swing of 17 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.
- Oct–Dec 202574 flights64.4%
- Jan–Mar 202666 flights81.2%
- Apr–Jun 202667 flights79.1%
- Jul–Sep 202660 flights79.7%
Scale runs 55% to 85%.
By weekday, OO 3439 did best on Tuesday at 85.0% on time and worst on Friday at 61.0%. Each day rests on about 38 flights, so a gap of 24 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late OO 3439 runs when it is late
The 64 late arrivals split 23 under half an hour, 22 between 30 and 60 minutes, and 19 an hour or more.
- 15+ min early56 flights21.3%
- Within 15 min143 flights54.4%
- 15–29 min late23 flights8.7%
- 30–59 min late22 flights8.4%
- 1–2 hours late17 flights6.5%
- 2+ hours late2 flights0.8%
Scale runs 0% to 100%.
Share of 263 completed flights by arrival against schedule.
23 of 85 late departures made up the time and arrived on time, 27% of them. Only 2 left on time and still arrived late.
The worst days
Worst days for OO 3439
The latest arrival of the period was on 29 May 2026, 3 hours 50 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 |
|---|---|---|
| 29 May 2026 | 3 hours 50 minutes | National Airspace System |
| 29 October 2025 | 2 hours 54 minutes | Late-arriving aircraft |
| 31 October 2025 | 1 hour 46 minutes | Late-arriving aircraft |
| 20 December 2025 | 1 hour 44 minutes | Late-arriving aircraft |
| 18 May 2026 | 1 hour 41 minutes | National Airspace System |
Delay causes
Why OO 3439 runs late
Late-arriving aircraft accounts for 46% of the 3,097 delay minutes carriers reported here, and the remaining four split what is left.
- 46%Late-arriving aircraft
- 41%National Airspace System
- 10%Carrier
- 3%Extreme weather
46% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 3,097 reported delay minutes here, that single category outweighs weather by 15 to one. The split is drawn from 3,097 delay minutes reported on OO 3439.
Cancellations sit at 1.12% against a national 1.89%, which is ordinary. Diversions add another 0.37%.
Connections and routes
What a delay on this flight costs
7.2% 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 roughly 50 minutes, which a normal layover absorbs.
The same number turns up on two other city pairs in the data, including SMF to SAN (228) and PDX to SEA (29), but none flew often enough under OO 3439 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SAN to SMF only.
One caution: this is a thin sample. 267 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 3439
For a booking, read OO 3439 as 75.7% on time with 1.12% cancelled over 267 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- SAN to SMF, every carrier and departure
- SMF to SAN, the return direction
- San Diego International (SAN) delay statistics
- Sacramento International (SMF) 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
- Why the first flight of the morning is statistically safest
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.