Flight number record
OO 4800
SkyWest Airlines · Grand Junction to Denver
- Route
- GJT → DEN
- Departs
- 05:30
- Flights
- 318
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 4800, 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 4800 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 10 points better than the national rate of 77.3%. When something does go wrong the average delay runs close to two hours. That rests on 318 flights, with a median arrival 20 minutes early.
Set against the rest of the country, OO 4800's record is 10 points better than the US average of 77.3%. That gap is worth roughly 101 fewer late arrivals for every thousand flights.
Key figures
On time
87.4%
Arrivals under 15 minutes late, of 318 completed flights
Avg delay
121 min
Across delayed arrivals only, not all flights
Cancelled
0.00%
National rate is 1.89%
1 hour+ late
5.7%
National rate is 8.3%
These figures cover 318 flights between September 2025 and August 2026. The median arrival is 20 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 4800 flies
OO 4800 is scheduled to leave Grand Junction (GJT) at 05:30 local time and reach Denver (DEN) at 07:00. That slot held for 318 of the 318 scheduled departures in the data, so the figures below describe one steady operation rather than a number that moved around the clock.
- Departs 05:30318 flights100.0%
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 05:30 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and OO 4800 runs level with that at 87.4%. 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 4800 next to GJT to DEN
Every carrier on GJT to DEN combined arrived on time 79.6% of the time across 2,282 flights, so OO 4800 is 8 points ahead of it. SkyWest flew 1,550 flights on the same city pair under all its flight numbers, including this one, and those ran 77.0% on time. Across its whole network SkyWest Airlines managed 78.7%, which this flight beats by 9 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| OO 4800thin sample | 318 | 87.4% | 121 min | 0.00% | A+ |
| All SkyWest Airlines on GJT–DEN | 1,550 | 77.0% | 80 min | 1.81% | B |
| All carriers on GJT–DEN | 2,282 | 79.6% | 75 min | 1.36% | B |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 4800 quarter by quarter
OO 4800 did not run the same all year. Its best quarter was Oct–Dec 2025 at 92.2% on time and its weakest Jan–Mar 2026 at 80.8%, a swing of 11 points on roughly 64 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 flights90.0%
- Oct–Dec 202577 flights92.2%
- Jan–Mar 202673 flights80.8%
- Apr–Jun 202685 flights90.6%
- Jul–Sep 202653 flights83.0%
Scale runs 70% to 100%.
By weekday, OO 4800 did best on Tuesday at 93.2% on time and worst on Sunday at 79.6%. Each day rests on about 45 flights, so a gap of 14 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late OO 4800 runs when it is late
OO 4800 often beats the schedule: 207 of 318 completed flights, 65%, arrived 15 minutes or more early. The 40 late arrivals split 10 under half an hour, 12 between 30 and 60 minutes, and 18 an hour or more.
- 15+ min early207 flights65.1%
- Within 15 min71 flights22.3%
- 15–29 min late10 flights3.1%
- 30–59 min late12 flights3.8%
- 1–2 hours late5 flights1.6%
- 2+ hours late13 flights4.1%
Scale runs 0% to 100%.
Share of 318 completed flights by arrival against schedule.
Time lost at the gate mostly stays lost. Of 34 departures that left 15 minutes late or more, only 4 made it up before arrival. 10 flights left on time and still arrived late.
The worst days
Worst days for OO 4800
The latest arrival of the period was on 15 October 2025, 7 hours 21 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on five of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 15 October 2025 | 7 hours 21 minutes | Carrier |
| 9 August 2026 | 7 hours 15 minutes | Carrier |
| 16 August 2026 | 6 hours 47 minutes | Carrier |
| 17 April 2026 | 5 hours 51 minutes | Carrier |
| 17 January 2026 | 4 hours 13 minutes | Carrier |
Delay causes
Why OO 4800 runs late
Carrier accounts for 82% of the 4,828 delay minutes carriers reported here, and the remaining four split what is left.
- 82%Carrier
- 14%Late-arriving aircraft
- 4%National Airspace System
- 1%Extreme weather
The largest share of delay minutes, 82%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 3,937 of the 4,828 delay minutes reported here. The split is drawn from 4,828 delay minutes reported on OO 4800.
Cancellations are rare at 0.00%, below the national 1.89% 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
5.7% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last close to two hours, which a normal layover absorbs.
The same number turns up on six other city pairs in the data, including CMH to ORD (19), DEN to SGF (12) and ORD to AVL (11), but none flew often enough under OO 4800 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to GJT to DEN only.
One caution: this is a thin sample. 318 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 4800
For a booking, OO 4800 has one of the better records a US domestic flight can show: 87.4% on time and 0.00% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- GJT to DEN, every carrier and departure
- DEN to GJT, the return direction
- SkyWest Airlines 4709 on the same route84.3%
- SkyWest Airlines 5755 on the same route64.3%
- SkyWest Airlines 4635 on the same route67.6%
- United Airlines 1877 on the same route86.3%
- Denver International (DEN) 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
- How to read this site: grades, sample sizes, and honest caveats
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.