Carrier route record
UAORD→TYS
United Airlines · Chicago to Knoxville
- Flights
- 316
- Period
- July 2025 to June 2026
- Share of route
- 14%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on ORD to TYS draws a D. Roughly one flight in three arrives at least 15 minutes late, and the typical late arrival is an hour and a half behind schedule. Build slack into anything you connect to. That rests on 316 flights. The strongest carrier on the route with a full sample, SkyWest Airlines, flew 815 at 71.6% on time.
The national on-time rate over the same period is 77.6%, so United on ORD to TYS runs 17 points behind the country as a whole. Across a thousand flights that is about 166 extra late arrivals.
Key figures
On time
61.0%
Arrivals under 15 minutes late, of 308 completed flights
Avg delay
82 min
Across delayed arrivals only, not all flights
Cancelled
2.53%
National rate is 1.81%
Whole route
66.7%
Every carrier on ORD to TYS, 2,219 flights
These figures cover 316 flights between July 2025 and June 2026. Beyond the headline rate, 17.5% 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.
Carrier by carrier
United against every carrier on ORD to TYS
United flew 316 of the 2,219 flights on ORD to TYS, about 14% of it. Its 61.0% on time is 6 points worse than the route as a whole, which runs 66.7%. Ranked by on-time rate it is number four of five carriers on the route, where the range runs from Envoy at 79.1% to PSA at 60.2%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 71.6% of the time; PSA Airlines manages 60.2%. Sample sizes sit next to every figure, because a two-point gap across 834 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Envoy Airthin sample | 176 | 79.1% | 46 min | 2.27% | B |
| Republic Airwaysthin sample | 78 | 75.6% | 59 min | 0.00% | B+ |
| SkyWest Airlines | 815 | 71.6% | 75 min | 1.84% | C |
| United Airlines (this page)thin sample | 316 | 61.0% | 82 min | 2.53% | D |
| PSA Airlines | 834 | 60.2% | 143 min | 6.71% | D− |
PSA Airlines cancels 6.7% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Departure window
When United runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 316 flights.
- 5am–8am3 flights—
- 8am–11am—
- 11am–2pm—
- 2pm–5pm21 flights—
- 5pm–8pm154 flights60.0%
- 8pm–5am138 flights59.0%
Scale runs 50% to 65%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is the strongest at 60.0% on time. The full set of windows spans about a point.
Across the year
United on ORD to TYS through the year
- Jul–Sep 202595 flights57.1%
- Oct–Dec 202525 flights—
- Jan–Mar 202689 flights53.5%
- Apr–Jun 2026107 flights67.9%
Scale runs 45% to 75%. Rows with fewer than 30 flights show a dash.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 61.0% on time across 316 flights.
United on ORD to TYS did not run the same all year. Its best quarter was Apr–Jun 2026 at 67.9% on time and its weakest Jan–Mar 2026 at 53.5%, a swing of 14 points on roughly 105 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.
Across the week, Saturday is the strongest day at 70.2% on time and Tuesday the weakest at 50.0%. 20 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 54% of the 9,864 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.
- 54%Late-arriving aircraft
- 25%Carrier
- 14%National Airspace System
- 7%Extreme weather
54% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 9,864 reported delay minutes here, that single category outweighs weather by 8 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 9,864 reported delay minutes.
Cancellations run at 2.53%, against 1.81% nationally. That is about one flight in 40 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 17.5% 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.
At 475 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5pm–8pm window matters as much as it does.
The return leg is a different operation and performs like one: it runs 86.4% on time across 317 flights, 25 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 25 points of difference.
One caution: this is a thin sample. 316 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 United on ORD to TYS
Put together: treat all of this as provisional. 316 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 61.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 308 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to TYS, every carrier
- United on TYS to ORD, the return leg
- Envoy Air on ORD to TYS79.1%
- SkyWest Airlines on ORD to TYS71.6%
- PSA Airlines on ORD to TYS60.2%
- United Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- The US routes with the most cancellations
- Why the first flight of the morning is statistically safest
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.