Flight number record
OO 4777
SkyWest Airlines · Des Moines to Denver
- Route
- DSM → DEN
- Departs
- 05:30
- Flights
- 305
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s OO 4777, 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 4777 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 11 points better than the national rate of 77.3%. When something does go wrong the average delay runs about 3.0 hours. That rests on 305 flights, with a median arrival 13 minutes early.
Set against the rest of the country, OO 4777's record is 11 points better than the US average of 77.3%. That gap is worth roughly 107 fewer late arrivals for every thousand flights.
Key figures
On time
88.0%
Arrivals under 15 minutes late, of 301 completed flights
Avg delay
178 min
Across delayed arrivals only, not all flights
Cancelled
1.31%
National rate is 1.89%
1 hour+ late
6.6%
National rate is 8.3%
These figures cover 305 flights between September 2025 and August 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.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Schedule
When OO 4777 flies
OO 4777 flies DSM to DEN without a single fixed slot. Its most common scheduled departure was 05:30, used on 150 of 305 flights, with 05:50 (75 flights) and 05:45 (73 flights) next.
- Departs 05:30150 flights49.2%
- Departs 05:5075 flights24.6%
- Departs 05:4573 flights23.9%
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 4777 runs level with that at 88.0%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Against the route
OO 4777 next to DSM to DEN
Every carrier on DSM to DEN combined arrived on time 83.5% of the time across 2,327 flights, so OO 4777 is 5 points ahead of it. SkyWest flew 907 flights on the same city pair under all its flight numbers, including this one, and those ran 90.6% 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 4777thin sample | 305 | 88.0% | 178 min | 1.31% | A |
| All SkyWest Airlines on DSM–DEN | 907 | 90.6% | 108 min | 0.77% | A+ |
| All carriers on DSM–DEN | 2,327 | 83.5% | 88 min | 0.64% | B+ |
| SkyWest Airlines, whole network | 855,406 | 78.7% | 88 min | 1.79% | B |
Across the year
OO 4777 quarter by quarter
Quarter by quarter OO 4777 held fairly steady: 87.7% in Oct–Dec 2025, 88.0% in Jan–Mar 2026, 91.2% in Apr–Jun 2026 and 83.9% in Jul–Sep 2026. A spread of 7 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.
- Oct–Dec 202566 flights87.7%
- Jan–Mar 202686 flights88.0%
- Apr–Jun 202691 flights91.2%
- Jul–Sep 202662 flights83.9%
Scale runs 75% to 95%.
By weekday, OO 4777 did best on Wednesday at 95.3% on time and worst on Saturday at 76.2%. Each day rests on about 44 flights, so a gap of 19 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late OO 4777 runs when it is late
OO 4777 often beats the schedule: 140 of 301 completed flights, 47%, arrived 15 minutes or more early. When OO 4777 is late it tends to be very late: 20 of its 36 late arrivals were an hour or more behind, and 13 were two hours or more.
- 15+ min early140 flights46.5%
- Within 15 min125 flights41.5%
- 15–29 min late10 flights3.3%
- 30–59 min late6 flights2.0%
- 1–2 hours late7 flights2.3%
- 2+ hours late13 flights4.3%
Scale runs 0% to 100%.
Share of 301 completed flights by arrival against schedule.
Time lost at the gate mostly stays lost. Of 31 departures that left 15 minutes late or more, only 2 made it up before arrival. 7 flights left on time and still arrived late.
The worst days
Worst days for OO 4777
The latest arrival of the period was on 28 March 2026, 15 hours 58 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The five worst days are spread across March, July, November and August, with no single month standing out.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 28 March 2026 | 15 hours 58 minutes | Carrier |
| 3 July 2026 | 9 hours 15 minutes | Extreme weather |
| 30 November 2025 | 8 hours 50 minutes | Extreme weather |
| 19 March 2026 | 8 hours 50 minutes | Late-arriving aircraft |
| 16 August 2026 | 8 hours 43 minutes | Carrier |
Delay causes
Why OO 4777 runs late
Carrier accounts for 61% of the 6,400 delay minutes carriers reported here, and the remaining four split what is left.
- 61%Carrier
- 29%Extreme weather
- 8%Late-arriving aircraft
- 2%National Airspace System
- 0%Security
Extreme weather accounts for 29% 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 4.8 times the usual weather exposure. The split is drawn from 6,400 delay minutes reported on OO 4777.
Cancellations sit at 1.31% against a national 1.89%, which is ordinary. Diversions add another 0.00%.
Connections and routes
What a delay on this flight costs
6.6% 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 about 3.0 hours, which a normal layover absorbs.
The 589 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty.
The same number turns up on two other city pairs in the data, including SFO to SNA (55) and FAR to DEN (1), but none flew often enough under OO 4777 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to DSM to DEN only.
One caution: this is a thin sample. 305 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 4777
For a booking, OO 4777 has one of the better records a US domestic flight can show: 88.0% on time and 1.31% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- DSM to DEN, every carrier and departure
- DEN to DSM, the return direction
- United Airlines 1781 on the same route65.3%
- 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
- 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.