Flight number record

OO 4234

SkyWest Airlines · Salt Lake City to Grand Junction

Route: SLC → GJT
Departs: 21:30
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 4234, 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 4234 earns an A+. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 20 points better than the national rate of 77.6%. When something does go wrong the average delay runs close to two hours. That rests on 365 flights, with a median arrival 18 minutes early.

Set against the rest of the country, OO 4234's record is 20 points better than the US average of 77.6%. That gap is worth roughly 196 fewer late arrivals for every thousand flights.

On time

97.2%

Arrivals under 15 minutes late, of 363 completed flights

Avg delay

121 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

1 hour+ late

1.1%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. The median arrival is 18 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 4234 flies

OO 4234 flies SLC to GJT without a single fixed slot. Its most common scheduled departure was 21:30, used on 150 of 365 flights, with 20:55 (97 flights) and 20:50 (74 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 21:30150 flights41.1%
Departs 20:5597 flights26.6%
Departs 20:5074 flights20.3%

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 21:30 departure sits in the 8pm–5am window. Across every US flight scheduled in that window the on-time rate is 70.5%, and OO 4234 runs 27 points better at 97.2%. 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 4234 next to SLC to GJT

Every carrier on SLC to GJT combined arrived on time 95.3% of the time across 582 flights, so OO 4234 is 2 points ahead of it. Across its whole network SkyWest Airlines managed 79.0%, which this flight beats by 18 points.

OO 4234 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 4234	365	97.2%	121 min	0.00%	A+
All SkyWest Airlines on SLC–GJT	582	95.3%	76 min	0.00%	A+
All carriers on SLC–GJT	582	95.3%	76 min	0.00%	A+
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 4234 quarter by quarter

Quarter by quarter OO 4234 held fairly steady: 95.7% in Jul–Sep 2025, 98.9% in Oct–Dec 2025, 97.8% in Jan–Mar 2026 and 96.7% in Apr–Jun 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 202592 flights95.7%
Oct–Dec 202592 flights98.9%
Jan–Mar 202690 flights97.8%
Apr–Jun 202691 flights96.7%

Scale runs 85% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, OO 4234 ranged from 90.2% on Friday to 100.0% on Wednesday. With about 52 flights behind each day, a spread of 10 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why OO 4234 runs late

One category carries most of the weight here. Carrier accounts for 89% of the 1,206 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
89%
Extreme weather
7%
National Airspace System
3%

The largest share of delay minutes, 89%, 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 1,074 of the 1,206 delay minutes reported here. The split is drawn from 1,206 delay minutes reported on OO 4234.

Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are 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 1.1% 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.

Every one of the 365 flights under OO 4234 in the data flew SLC to GJT. The number was not reused on any other city pair, which makes this a clean record of one route.

One caution: this is a thin sample. 365 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 4234

For a booking, OO 4234 has one of the better records a US domestic flight can show: 97.2% on time and 0.00% 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