Flight number record
OO 3985
SkyWest Airlines · Salt Lake City to Hailey
- Route
- SLC → SUN
- Departs
- 20:45
- Flights
- 253
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 3985, 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 3985 earns an A+. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 19 points better than the national rate of 77.3%. When something does go wrong the average delay runs about 45 minutes. That rests on 253 flights, with a median arrival 15 minutes early.
Set against the rest of the country, OO 3985's record is 19 points better than the US average of 77.3%. That gap is worth roughly 187 fewer late arrivals for every thousand flights.
Key figures
On time
96.0%
Arrivals under 15 minutes late, of 248 completed flights
Avg delay
44 min
Across delayed arrivals only, not all flights
Cancelled
0.79%
National rate is 1.89%
1 hour+ late
0.8%
National rate is 8.3%
These figures cover 253 flights between September 2025 and August 2026. The median arrival is 15 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 3985 flies
OO 3985 flies SLC to SUN without a single fixed slot. Its most common scheduled departure was 20:45, used on 98 of 253 flights, with 21:05 (86 flights) and 20:55 (29 flights) next.
- Departs 20:4598 flights38.7%
- Departs 21:0586 flights34.0%
- Departs 20:5529 flights11.5%
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 20:45 departure sits in the 8pm–5am window. Across every US flight scheduled in that window the on-time rate is 70.1%, and OO 3985 runs 26 points better at 96.0%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
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Against the route
OO 3985 next to SLC to SUN
Every carrier on SLC to SUN combined arrived on time 93.5% of the time across 1,078 flights, so OO 3985 is 3 points ahead of it. Across its whole network SkyWest Airlines managed 78.7%, which this flight beats by 17 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| OO 3985thin sample | 253 | 96.0% | 44 min | 0.79% | A+ |
| All SkyWest Airlines on SLC–SUN | 1,078 | 93.5% | 52 min | 0.74% | A+ |
| All carriers on SLC–SUN | 1,078 | 93.5% | 52 min | 0.74% | A+ |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 3985 quarter by quarter
Quarter by quarter OO 3985 held fairly steady: 93.0% in Jan–Mar 2026, 98.9% in Apr–Jun 2026 and 95.2% in Jul–Sep 2026. A spread of 6 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.
- Oct–Dec 202512 flights—
- Jan–Mar 202690 flights93.0%
- Apr–Jun 202689 flights98.9%
- Jul–Sep 202662 flights95.2%
Scale runs 85% to 100%. Rows with fewer than 30 flights show a dash.
By weekday, OO 3985 ranged from 91.9% on Saturday to 100.0% on Friday. With about 36 flights behind each day, a spread of 8 points is inside normal variation, so the day you fly is not worth changing for this flight.
Arrival by arrival
How late OO 3985 runs when it is late
OO 3985 often beats the schedule: 132 of 248 completed flights, 53%, arrived 15 minutes or more early. Most of the lateness is short. 6 of the 10 late arrivals were under half an hour behind, and 2 reached an hour or more.
- 15+ min early132 flights53.2%
- Within 15 min106 flights42.7%
- 15–29 min late6 flights2.4%
- 30–59 min late2 flights0.8%
- 1–2 hours late1 flights0.4%
- 2+ hours late1 flights0.4%
Scale runs 0% to 100%.
Share of 248 completed flights by arrival against schedule.
Only 13 of 248 completed flights left 15 minutes late or more, too few to say how often the time is made up.
The worst days
Worst days for OO 3985
The latest arrival of the period was on 16 March 2026, 2 hours 32 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 |
|---|---|---|
| 16 March 2026 | 2 hours 32 minutes | Carrier |
| 15 July 2026 | 1 hour 13 minutes | Carrier |
| 19 February 2026 | 58 minutes | Carrier |
| 11 July 2026 | 38 minutes | Carrier |
| 14 February 2026 | 28 minutes | Carrier |
Delay causes
Why OO 3985 runs late
Carrier accounts for 92% of the 444 delay minutes carriers reported here, and the remaining four split what is left.
- 92%Carrier
- 8%Extreme weather
The largest share of delay minutes, 92%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 407 of the 444 delay minutes reported here. The split is drawn from 444 delay minutes reported on OO 3985.
Cancellations are rare at 0.79%, below the national 1.89% 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 0.8% land an hour or more behind schedule, against 8.3% 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 three other city pairs in the data, including LAX to SMF (68), DTW to GRR (1) and GRR to DTW (1), but none flew often enough under OO 3985 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SLC to SUN only.
One caution: this is a thin sample. 253 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 3985
For a booking, OO 3985 has one of the better records a US domestic flight can show: 96.0% on time and 0.79% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- SLC to SUN, every carrier and departure
- SUN to SLC, the return direction
- SkyWest Airlines 3973 on the same route92.4%
- Salt Lake City International (SLC) 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
- Worst months to fly in the US, ranked by the data
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.