Flight number record
YX 3609
Republic Airways · Newark to Louisville
- Route
- EWR → SDF
- Departs
- 20:29
- Flights
- 269
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s YX 3609, check with Republic Airways. Republic Airways flies under contract for larger airlines, so a ticket for this flight may show a different airline code and number.
YX 3609 lands a B−, level with the national rate of 77.6%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 269 flights, with a median arrival 13 minutes early.
Key figures
On time
77.1%
Arrivals under 15 minutes late, of 245 completed flights
Avg delay
86 min
Across delayed arrivals only, not all flights
Cancelled
8.92%
National rate is 1.81%
1 hour+ late
12.2%
National rate is 8.1%
These figures cover 269 flights between July 2025 and June 2026. Beyond the headline rate, 12.2% 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 YX 3609 flies
YX 3609 flies EWR to SDF without a single fixed slot. Its most common scheduled departure was 20:29, used on 68 of 269 flights, with 20:45 (37 flights) and 20:30 (32 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 20:2968 flights25.3%
- Departs 20:4537 flights13.8%
- Departs 20:3032 flights11.9%
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 20:29 departure sits in the 8pm–5am window. Across every US flight scheduled in that window the on-time rate is 70.5%, and YX 3609 runs 7 points better at 77.1%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
Against the route
YX 3609 next to EWR to SDF
Every carrier on EWR to SDF combined arrived on time 81.9% of the time across 973 flights, so YX 3609 is 5 points behind it. Republic flew 958 flights on the same city pair under all its flight numbers, including this one, and those ran 81.9% on time. Across its whole network Republic Airways managed 78.5%, close to this flight's figure.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| YX 3609thin sample | 269 | 77.1% | 86 min | 8.92% | B− |
| All Republic Airways on EWR–SDF | 958 | 81.9% | 73 min | 4.80% | B− |
| All carriers on EWR–SDF | 973 | 81.9% | 72 min | 4.73% | B− |
| Republic Airways, whole network | 361,482 | 78.5% | 72 min | 4.08% | B− |
Across the year
YX 3609 quarter by quarter
YX 3609 did not run the same all year. Its best quarter was Jan–Mar 2026 at 83.5% on time and its weakest Jul–Sep 2025 at 72.3%, a swing of 11 points on roughly 90 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 flights72.3%
- Oct–Dec 202590 flights75.9%
- Jan–Mar 202687 flights83.5%
Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.
By weekday, YX 3609 did best on Tuesday at 88.6% on time and worst on Sunday at 65.6%. Each day rests on about 38 flights, so a gap of 23 points is worth noticing but could still narrow in another year.
Delay causes
Why YX 3609 runs late
One category carries most of the weight here. Late-arriving aircraft accounts for 62% of the 4,836 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.
- 62%Late-arriving aircraft
- 25%Carrier
- 11%National Airspace System
- 2%Extreme weather
62% 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 4,836 reported delay minutes here, that single category outweighs weather by 36 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 4,836 delay minutes reported on YX 3609.
Cancellations run at 8.92%, against 1.81% nationally. That is about one flight in twelve 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 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. 12.2% 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 642 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.
The same number turns up on six other city pairs in the data, including MKE to EWR (41), ORD to ECP (15) and ORD to DTW (7), but none flew often enough under YX 3609 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to EWR to SDF only.
One caution: this is a thin sample. 269 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 YX 3609
For a booking, the cancellation rate is the figure to plan around on YX 3609: 8.92% of its 269 scheduled flights did not operate. A late arrival costs an hour and a half, but a cancellation costs the day, so leave a later option open.
Related
Where to go next
- EWR to SDF, every carrier and departure
- SDF to EWR, the return direction
- Newark Liberty International (EWR) delay statistics
- Republic Airways on-time record
- Every Republic Airways flight number with a record
- The most and least reliable flight numbers in the US
- Why the first flight of the morning is statistically safest
A flight number here means Republic Airways’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.