Flight number record

OO 4018

SkyWest Airlines · Los Angeles to San Diego

Route: LAX → SAN
Departs: 08:20
Flights: 310
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 4018, 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 4018 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 8 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 310 flights, with a median arrival 8 minutes early.

Set against the rest of the country, OO 4018's record is 8 points better than the US average of 77.6%. That gap is worth roughly 80 fewer late arrivals for every thousand flights.

On time

85.6%

Arrivals under 15 minutes late, of 306 completed flights

Avg delay

62 min

Across delayed arrivals only, not all flights

Cancelled

1.29%

National rate is 1.81%

1 hour+ late

5.6%

National rate is 8.1%

These figures cover 310 flights between July 2025 and June 2026. The median arrival is 8 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 4018 flies

OO 4018 flies LAX to SAN without a single fixed slot. Its most common scheduled departure was 08:20, used on 131 of 310 flights, with 09:00 (62 flights) and 08:15 (41 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 08:20131 flights42.3%
Departs 09:0062 flights20.0%
Departs 08:1541 flights13.2%

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 08:20 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and OO 4018 runs level with that at 85.6%. 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 4018 next to LAX to SAN

Every carrier on LAX to SAN combined arrived on time 86.7% of the time across 2,441 flights, so OO 4018 is about level with it. SkyWest flew 2,253 flights on the same city pair under all its flight numbers, including this one, and those ran 86.5% on time. Across its whole network SkyWest Airlines managed 79.0%, which this flight beats by 7 points.

OO 4018 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 4018thin sample	310	85.6%	62 min	1.29%	A
All SkyWest Airlines on LAX–SAN	2,253	86.5%	65 min	1.02%	A
All carriers on LAX–SAN	2,441	86.7%	64 min	0.94%	A+
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 4018 quarter by quarter

OO 4018 did not run the same all year. Its best quarter was Apr–Jun 2026 at 91.7% on time and its weakest Jan–Mar 2026 at 78.9%, a swing of 13 points on roughly 78 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 202592 flights89.1%
Oct–Dec 202592 flights86.4%
Jan–Mar 202690 flights78.9%
Apr–Jun 202636 flights91.7%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, OO 4018 ranged from 81.8% on Sunday to 88.6% on Wednesday. With about 44 flights behind each day, a spread of 7 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why OO 4018 runs late

One category carries most of the weight here. Carrier accounts for 58% of the 2,745 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.

Carrier
58%
National Airspace System
26%
Extreme weather
15%

Extreme weather accounts for 15% 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 2.4 times the usual weather exposure. The split is drawn from 2,745 delay minutes reported on OO 4018.

Cancellations sit at 1.29% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

5.6% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.

OO 4018 is not only a LAX to SAN flight. It also flew SAN to LAX (308 flights, 84.9% 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. 310 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.

Other routes flown as OO 4018
Also flown as	Flights	On time	Avg delay	Cancelled	Grade
SAN to LAXthin sample	308	84.9%	55 min	1.30%	B

What to do with this

Booking OO 4018

For a booking, OO 4018 has one of the better records a US domestic flight can show: 85.6% on time and 1.29% cancelled. That is a base rate, not a promise about any single day.

Where to go next

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, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures