Route reliability record
ATL→TYS
Atlanta to Knoxville
- Flights
- 1,722
- Period
- July 2025 to June 2026
- Distance
- 152 mi
- Carriers
- 1
This route lands a B, 5 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 1,722 ATL to TYS flights, with a median arrival 8 minutes early.
Best time to fly ATL to TYS: a 8am–11am departure, ideally on a Monday. Flights in that window arrived on time 88.5% of the time and Monday flights 85.6%, against 82.8% for the route overall.
Set against the rest of the country, this route's record is 5 points better than the US average of 77.6%. That gap is worth roughly 52 fewer late arrivals for every thousand flights.
Key figures
On time
82.8%
Arrivals under 15 minutes late, of 1,688 completed flights
Avg delay
58 min
Across delayed arrivals only, not all flights
Cancelled
1.86%
National rate is 1.81%
Best carrier
Delta
82.8% on time across 1,722 flights
These figures cover 1,722 flights between July 2025 and June 2026. The median arrival is 8 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.
Carrier by carrier
Which airline is most reliable on ATL to TYS
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 1,722 | 82.8% | 58 min | 1.86% | B |
Flight by flight
Flights on ATL to TYS
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
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 11 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am397 flights88.5%
- 11am–2pm271 flights87.1%
- 2pm–5pm532 flights78.7%
- 5pm–8pm190 flights77.6%
- 8pm–5am332 flights82.2%
Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 88.5% of the time, against 77.6% for the evening window. That is 11 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 532 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 16 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.
July is the worst month at 72.9% on time, 16 points below October, the best at 88.9%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. October was the busiest month here, with 180 flights.
Across the week, Monday is the strongest day at 85.6% on time and Friday the weakest at 79.4%. 6 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Carrier accounts for 56% of the 17,000 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.
- 56%Carrier
- 26%Late-arriving aircraft
- 11%National Airspace System
- 7%Extreme weather
The largest share of delay minutes, 56%, 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 9,404 of the 17,000 delay minutes reported here. The split is drawn from 16,872 reported delay minutes.
Cancellations sit at 1.86% against a national 1.81%, which is ordinary. Diversions add another 0.12%.
Connections and stage length
What a delay here actually costs
Badly late arrivals are rare here: only 4.7% land an hour or more behind schedule, against 8.1% 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.
At 152 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 8am–11am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 87.6% on time across 1,724 flights, 5 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 5 points of difference.
The sample behind these figures is 1,722 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.
Work out the risk of missing a connection in TYS after this flight
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. October runs 88.9% on time and July 72.9%, a swing of 16 points. If the dates move at all, move them out of July before you think about anything else. 1,688 completed flights over 12 months sit behind that.
Common questions
ATL to TYS questions
How often is ATL to TYS delayed?
About one flight in six arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 17.2% of the 1,722 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.
How reliable is ATL to TYS compared with the rest of the country?
82.8% of flights arrive on time here against a national 77.6%, a difference of 5 points in its favour. That is worth a B on this site's grading scale.
What time of day has the fewest delays on ATL to TYS?
The 8am–11am departure window is the strongest at 88.5% on time. The 5pm–8pm window is the weakest at 77.6%, 11 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 July delays on ATL to TYS?
July is the weakest month at 72.9% on time, compared with 88.9% in October. Across the year that is 16 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
- TYS to ATL — the return legseparate record
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- ATL to LGA, a related route73.4%
- ORD to TYS, a related route66.7%
- ATL to MCO, a related route70.7%
- Delta Air Lines on-time record82.8%
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
Direction matters. ATL to TYS and TYS to ATL are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed ATL to TYS’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
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.