Flight number record

OO 3983

SkyWest Airlines · Los Angeles to San Jose

Route: LAX → SJC
Departs: 21:35
Flights: 255
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 3983, 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 3983 earns an A+. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 12 points better than the national rate of 77.6%. When something does go wrong the average delay runs about 45 minutes. That rests on 255 flights, with a median arrival 13 minutes early.

Set against the rest of the country, OO 3983's record is 12 points better than the US average of 77.6%. That gap is worth roughly 122 fewer late arrivals for every thousand flights.

On time

89.8%

Arrivals under 15 minutes late, of 254 completed flights

Avg delay

44 min

Across delayed arrivals only, not all flights

Cancelled

0.39%

National rate is 1.81%

1 hour+ late

3.1%

National rate is 8.1%

These figures cover 255 flights between July 2025 and June 2026. The median arrival is 13 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 3983 flies

OO 3983 flies LAX to SJC without a single fixed slot. Its most common scheduled departure was 21:35, used on 98 of 255 flights, with 20:55 (32 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 21:3598 flights38.4%
Departs 20:5532 flights12.5%

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 21:35 departure sits in the 8pm–5am window. Across every US flight scheduled in that window the on-time rate is 70.5%, and OO 3983 runs 19 points better at 89.8%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.

Against the route

OO 3983 next to LAX to SJC

Every carrier on LAX to SJC combined arrived on time 86.6% of the time across 4,429 flights, so OO 3983 is 3 points ahead of it. SkyWest flew 2,049 flights on the same city pair under all its flight numbers, including this one, and those ran 91.4% on time. Across its whole network SkyWest Airlines managed 79.0%, which this flight beats by 11 points.

OO 3983 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 3983thin sample	255	89.8%	44 min	0.39%	A+
All SkyWest Airlines on LAX–SJC	2,049	91.4%	55 min	0.34%	A+
All carriers on LAX–SJC	4,429	86.6%	52 min	0.79%	A+
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 3983 quarter by quarter

Quarter by quarter OO 3983 held fairly steady: 88.6% in Jul–Sep 2025, 91.5% in Oct–Dec 2025 and 89.1% in Jan–Mar 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 202588 flights88.6%
Oct–Dec 202583 flights91.5%
Jan–Mar 202664 flights89.1%
Apr–Jun 202620 flights—

Scale runs 80% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, OO 3983 did best on Tuesday at 97.5% on time and worst on Friday at 80.6%. Each day rests on about 36 flights, so a gap of 17 points is worth noticing but could still narrow in another year.

Delay causes

Why OO 3983 runs late

One category carries most of the weight here. Carrier accounts for 75% of the 1,153 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
75%
Extreme weather
17%
National Airspace System
8%

Extreme weather accounts for 17% 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 2.8 times the usual weather exposure. The split is drawn from 1,153 delay minutes reported on OO 3983.

Cancellations are rare at 0.39%, below the national 1.81% 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 3.1% 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.

The same number turns up on four other city pairs in the data, including DTW to BUF (36), BUF to DTW (36) and SEA to SNA (1), but none flew often enough under OO 3983 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to LAX to SJC only.

One caution: this is a thin sample. 255 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 3983

For a booking, OO 3983 has one of the better records a US domestic flight can show: 89.8% on time and 0.39% 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