Flight number record
OO 4821
SkyWest Airlines · Dallas-Fort Worth to Grand Island
- Route
- DFW → GRI
- Departs
- 15:32
- Flights
- 352
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s OO 4821, 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 4821 sits in the middle of the pack with a B. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 352 flights, with a median arrival 10 minutes early.
Key figures
On time
75.0%
Arrivals under 15 minutes late, of 344 completed flights
Avg delay
78 min
Across delayed arrivals only, not all flights
Cancelled
1.70%
National rate is 1.81%
1 hour+ late
11.3%
National rate is 8.1%
These figures cover 352 flights between July 2025 and June 2026. Beyond the headline rate, 11.3% 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 4821 flies
OO 4821 flies DFW to GRI without a single fixed slot. Its most common scheduled departure was 15:32, used on 81 of 352 flights, with 12:29 (64 flights) and 15:30 (41 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 15:3281 flights23.0%
- Departs 12:2964 flights18.2%
- Departs 15:3041 flights11.6%
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 15:32 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and OO 4821 runs 3 points better at 75.0%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
Against the route
OO 4821 next to DFW to GRI
Every carrier on DFW to GRI combined arrived on time 75.3% of the time across 712 flights, so OO 4821 is about level with it. Across its whole network SkyWest Airlines managed 79.0%, which this flight trails by 4 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| OO 4821thin sample | 352 | 75.0% | 78 min | 1.70% | B |
| All SkyWest Airlines on DFW–GRI | 712 | 75.3% | 106 min | 3.09% | B− |
| All carriers on DFW–GRI | 712 | 75.3% | 106 min | 3.09% | B− |
| SkyWest Airlines, whole network | 852,935 | 79.0% | 88 min | 1.77% | B |
Across the year
OO 4821 quarter by quarter
OO 4821 did not run the same all year. Its best quarter was Jul–Sep 2025 at 82.4% on time and its weakest Apr–Jun 2026 at 68.0%, a swing of 14 points on roughly 88 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 202592 flights82.4%
- Oct–Dec 202592 flights77.8%
- Jan–Mar 202690 flights70.5%
- Apr–Jun 202678 flights68.0%
Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.
By weekday, OO 4821 did best on Wednesday at 86.3% on time and worst on Saturday at 59.2%. Each day rests on about 50 flights, so a gap of 27 points is worth noticing but could still narrow in another year.
Delay causes
Why OO 4821 runs late
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 6,677 reported delay minutes.
- 40%Carrier
- 31%Late-arriving aircraft
- 18%Extreme weather
- 11%National Airspace System
Extreme weather accounts for 18% 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 2.9 times the usual weather exposure. The split is drawn from 6,677 delay minutes reported on OO 4821.
Cancellations sit at 1.70% against a national 1.81%, which is ordinary. Diversions add another 0.57%.
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. 11.3% 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 562 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
OO 4821 is not only a DFW to GRI flight. It also flew GRI to DFW (347 flights, 74.6% on time) often enough to be scored on its own. Airlines attach one number to several legs of an aircraft's day, and each leg keeps its own record here, so check which city pair is on your booking before reading a rate.
One caution: this is a thin sample. 352 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.
| Also flown as | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| GRI to DFWthin sample | 347 | 74.6% | 128 min | 3.17% | C− |
What to do with this
Booking OO 4821
For a booking, read OO 4821 as 75.0% on time with 1.70% cancelled over 352 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- DFW to GRI, every carrier and departure
- GRI to DFW, the return direction
- SkyWest Airlines 4823 on the same route75.5%
- Dallas/Fort Worth International (DFW) 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
- The best time of day to fly, according to 7.04 million flight records
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.