Flight number record
OO 3951
SkyWest Airlines · Los Angeles to Phoenix
- Route
- LAX → PHX
- Departs
- 10:01
- Flights
- 289
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 3951, 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 3951 earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 10 points better than the national rate of 77.3%. When something does go wrong the average delay runs a little over an hour. That rests on 289 flights, with a median arrival 7 minutes early.
Set against the rest of the country, OO 3951's record is 10 points better than the US average of 77.3%. That gap is worth roughly 95 fewer late arrivals for every thousand flights.
Key figures
On time
86.8%
Arrivals under 15 minutes late, of 288 completed flights
Avg delay
70 min
Across delayed arrivals only, not all flights
Cancelled
0.35%
National rate is 1.89%
1 hour+ late
4.2%
National rate is 8.3%
These figures cover 289 flights between September 2025 and August 2026. The median arrival is 7 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 3951 flies
OO 3951 flies LAX to PHX without a single fixed slot. Its most common scheduled departure was 10:01, used on 93 of 289 flights, with 10:00 (65 flights) and 10:05 (46 flights) next.
- Departs 10:0193 flights32.2%
- Departs 10:0065 flights22.5%
- Departs 10:0546 flights15.9%
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 10:01 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 83.9%, and OO 3951 runs 3 points better at 86.8%. 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 3951 next to LAX to PHX
Every carrier on LAX to PHX combined arrived on time 80.3% of the time across 7,623 flights, so OO 3951 is 7 points ahead of it. SkyWest flew 2,677 flights on the same city pair under all its flight numbers, including this one, and those ran 87.2% on time. Across its whole network SkyWest Airlines managed 78.7%, which this flight beats by 8 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| OO 3951thin sample | 289 | 86.8% | 70 min | 0.35% | A+ |
| All SkyWest Airlines on LAX–PHX | 2,677 | 87.2% | 61 min | 0.71% | A+ |
| All carriers on LAX–PHX | 7,623 | 80.3% | 68 min | 0.77% | B+ |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 3951 quarter by quarter
OO 3951 did not run the same all year. Its best quarter was Jul–Sep 2025 at 93.3% on time and its weakest Jan–Mar 2026 at 80.0%, a swing of 13 points on roughly 58 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 flights93.3%
- Oct–Dec 202578 flights88.3%
- Jan–Mar 202645 flights80.0%
- Apr–Jun 202687 flights85.1%
- Jul–Sep 202649 flights89.8%
Scale runs 70% to 100%.
By weekday, OO 3951 did best on Monday at 93.3% on time and worst on Friday at 76.2%. Each day rests on about 41 flights, so a gap of 17 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late OO 3951 runs when it is late
The 38 late arrivals split 16 under half an hour, 10 between 30 and 60 minutes, and 12 an hour or more.
- 15+ min early68 flights23.6%
- Within 15 min182 flights63.2%
- 15–29 min late16 flights5.6%
- 30–59 min late10 flights3.5%
- 1–2 hours late6 flights2.1%
- 2+ hours late6 flights2.1%
Scale runs 0% to 100%.
Share of 288 completed flights by arrival against schedule.
4 of 30 late departures made up the time and arrived on time, 13% of them. 12 flights left on time and still arrived late.
The worst days
Worst days for OO 3951
The latest arrival of the period was on 26 September 2025, 9 hours 1 minute behind schedule; most of its delay minutes were filed as national airspace system delay. 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 |
|---|---|---|
| 26 September 2025 | 9 hours 1 minute | National Airspace System |
| 18 April 2026 | 3 hours 10 minutes | Carrier |
| 21 June 2026 | 2 hours 59 minutes | Carrier |
| 3 April 2026 | 2 hours 54 minutes | Carrier |
| 4 June 2026 | 2 hours 50 minutes | Carrier |
Delay causes
Why OO 3951 runs late
Carrier accounts for 64% of the 2,646 delay minutes carriers reported here, and the remaining four split what is left.
- 64%Carrier
- 29%National Airspace System
- 7%Extreme weather
The largest share of delay minutes, 64%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 1,696 of the 2,646 delay minutes reported here. The split is drawn from 2,646 delay minutes reported on OO 3951.
Cancellations are rare at 0.35%, below the national 1.89% and low enough to earn the plus on the grade. Roughly one flight in 100 is 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 4.2% 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.
OO 3951 is not only a LAX to PHX flight. It also flew PHX to LAX (270 flights, 87.7% on time) often enough to be scored on its own. Airlines attach one number to several legs of an aircraft's day, and each leg keeps its own record here, so check which city pair is on your booking before reading a rate.
One caution: this is a thin sample. 289 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.
| Also flown as | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| PHX to LAXthin sample | 270 | 87.7% | 74 min | 0.37% | A+ |
What to do with this
Booking OO 3951
For a booking, OO 3951 has one of the better records a US domestic flight can show: 86.8% on time and 0.35% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- LAX to PHX, every carrier and departure
- PHX to LAX, the return direction
- SkyWest Airlines 3894 on the same route88.2%
- SkyWest Airlines 4119 on the same route84.8%
- Los Angeles International (LAX) delay statistics
- Phoenix Sky Harbor International (PHX) 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.