Route reliability record
TYS→ORD
Knoxville to Chicago
- Flights
- 2,220
- Period
- July 2025 to June 2026
- Distance
- 475 mi
- Carriers
- 5
This route carries a cancellation problem, not just a delay problem: 4.0% of scheduled flights never operate, against 1.8% nationally. Of the ones that do fly, about seven flights in ten arrive on time, worth a C− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 2,220 flights, of which SkyWest Airlines flew 815 at 66.7% on time.
The national on-time rate over the same period is 77.6%, so this route runs 9 points behind the country as a whole. Across a thousand flights that is about 94 extra late arrivals.
Key figures
On time
68.2%
Arrivals under 15 minutes late, of 2,116 completed flights
Avg delay
106 min
Across delayed arrivals only, not all flights
Cancelled
4.01%
National rate is 1.81%
Best carrier
SkyWest
66.7% on time across 815 flights
These figures cover 2,220 flights between July 2025 and June 2026. Beyond the headline rate, 15.4% 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
Which airline is most reliable on TYS to ORD
The choice of carrier is not cosmetic here. SkyWest Airlines arrives on time 66.7% of the time; PSA Airlines manages 60.6%. 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 |
|---|---|---|---|---|---|
| United Airlinesthin sample | 317 | 86.4% | 85 min | 2.52% | A |
| Envoy Airthin sample | 175 | 75.9% | 57 min | 1.71% | B |
| Republic Airwaysthin sample | 79 | 70.9% | 84 min | 0.00% | C+ |
| SkyWest Airlines | 815 | 66.7% | 110 min | 2.94% | C |
| PSA Airlines | 834 | 60.6% | 113 min | 6.47% | D− |
PSA Airlines cancels 6.5% 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
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 32 points, against 6 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am403 flights84.5%
- 8am–11am379 flights71.3%
- 11am–2pm524 flights70.4%
- 2pm–5pm359 flights64.3%
- 5pm–8pm510 flights52.9%
- 8pm–5am45 flights71.1%
Scale runs 45% to 90%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 52.9% on time, against 84.5% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 11am–2pm window is the busiest, with 524 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 34 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
December is the weak month at 45.1% on time, against 79.5% in April. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. July was the busiest month here, with 245 flights.
The day of the week is close to irrelevant here: 4 points separates the best day from the worst. Weekly demand peaks are not what drives the delays on this operation.
Delay causes
Why this route gets delayed
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 71,000 reported delay minutes.
- 37%Late-arriving aircraft
- 36%Carrier
- 18%National Airspace System
- 9%Extreme weather
37% 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 71,000 reported delay minutes here, that single category outweighs weather by 4 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 71,157 reported delay minutes.
The largest share of delay minutes, 36%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 25,000 of the 71,000 delay minutes reported here.
Cancellations run at 4.01%, against 1.81% nationally. That is about one flight in 25 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 actually costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 15.4% 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 5am–8am window matters as much as it does.
The return leg runs 66.7% on time across 2,219 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 2,220 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking this route
Put together: the delay figures matter less here than the 4.01% cancellation rate. A late arrival costs you close to two hours; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 2,116 completed flights over 12 months sit behind that.
Common questions
TYS to ORD questions
How often is TYS to ORD delayed?
About one flight in three arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 31.8% of the 2,220 flights in this analysis, against 22.4% nationally. Delayed flights are late by close to two hours on average.
Which airline is most reliable on TYS to ORD?
SkyWest Airlines leads at 66.7% on time across 815 flights. PSA Airlines is at the other end on 60.6%, a gap of 6 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on TYS to ORD?
The 5am–8am departure window is the strongest at 84.5% on time. The 5pm–8pm window is the weakest at 52.9%, 32 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are December delays on TYS to ORD?
December is the weakest month at 45.1% on time, compared with 79.5% in April. Across the year that is 34 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- ORD to TYS — the return legseparate record
- Chicago O'Hare International (ORD) delay statistics
- United Airlines on-time record86.4%
- Envoy Air on-time record75.9%
- Republic Airways on-time record70.9%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Direction matters. TYS to ORD and ORD to TYS are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.