Flight number record

OO 6391

SkyWest Airlines · Tucson to Los Angeles

Route: TUS → LAX
Departs: 17:15
Flights: 258
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 6391, 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 6391 lands a B, about a point worse than the national rate of 77.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 258 flights, with a median arrival 9 minutes early.

On time

76.5%

Arrivals under 15 minutes late, of 255 completed flights

Avg delay

97 min

Across delayed arrivals only, not all flights

Cancelled

1.16%

National rate is 1.81%

1 hour+ late

10.2%

National rate is 8.1%

These figures cover 258 flights between July 2025 and June 2026. Beyond the headline rate, 10.2% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.

Schedule

When OO 6391 flies

OO 6391 flies TUS to LAX without a single fixed slot. Its most common scheduled departure was 17:15, used on 86 of 258 flights, with 17:55 (44 flights) and 18:51 (37 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 17:1586 flights33.3%
Departs 17:5544 flights17.1%
Departs 18:5137 flights14.3%

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 17:15 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.2%, and OO 6391 runs 8 points better at 76.5%. 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 6391 next to TUS to LAX

Every carrier on TUS to LAX combined arrived on time 85.9% of the time across 2,581 flights, so OO 6391 is 9 points behind it. SkyWest flew 2,115 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 trails by 3 points.

OO 6391 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 6391thin sample	258	76.5%	97 min	1.16%	B
All SkyWest Airlines on TUS–LAX	2,115	86.5%	85 min	0.43%	A+
All carriers on TUS–LAX	2,581	85.9%	77 min	0.43%	A+
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 6391 quarter by quarter

OO 6391 did not run the same all year. Its best quarter was Jan–Mar 2026 at 83.5% on time and its weakest Oct–Dec 2025 at 70.3%, a swing of 13 points on roughly 86 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 202591 flights75.6%
Oct–Dec 202576 flights70.3%
Jan–Mar 202685 flights83.5%
Apr–Jun 20266 flights—

Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, OO 6391 did best on Friday at 85.7% on time and worst on Sunday at 63.9%. Each day rests on about 37 flights, so a gap of 22 points is worth noticing but could still narrow in another year.

Delay causes

Why OO 6391 runs late

One category carries most of the weight here. Carrier accounts for 46% of the 5,817 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
46%
Late-arriving aircraft
28%
Security
15%
Extreme weather
8%
National Airspace System
3%

The largest share of delay minutes, 46%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 2,674 of the 5,817 delay minutes reported here. The split is drawn from 5,817 delay minutes reported on OO 6391.

Cancellations sit at 1.16% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.2% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.

The same number turns up on four other city pairs in the data, including SMF to LAX (44), GRR to ORD (41) and ORD to GRR (41), but none flew often enough under OO 6391 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to TUS to LAX only.

One caution: this is a thin sample. 258 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 6391

For a booking, OO 6391 is one of the weaker ways to fly TUS to LAX: 9 points below the route as a whole. If the schedule allows, compare it with the other departures listed on the route page before settling on this one.

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