Flight number record

YX 3653

Republic Airways · Louisville to Chicago

Route: SDF → ORD
Departs: 09:00
Flights: 303
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s YX 3653, 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 3653 lands a B, 6 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 a little over an hour on average. That is a workable record, not a spotless one. That rests on 303 flights, with a median arrival 4 minutes early.

Set against the rest of the country, YX 3653's record is 6 points better than the US average of 77.6%. That gap is worth roughly 56 fewer late arrivals for every thousand flights.

On time

83.2%

Arrivals under 15 minutes late, of 297 completed flights

Avg delay

73 min

Across delayed arrivals only, not all flights

Cancelled

1.98%

National rate is 1.81%

1 hour+ late

5.7%

National rate is 8.1%

These figures cover 303 flights between July 2025 and June 2026. The median arrival is 4 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.

Schedule

When YX 3653 flies

YX 3653 flies SDF to ORD without a single fixed slot. Its most common scheduled departure was 09:00, used on 98 of 303 flights, with 09:05 (55 flights) and 08:40 (49 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 09:0098 flights32.3%
Departs 09:0555 flights18.2%
Departs 08:4049 flights16.2%

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 09:00 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and YX 3653 runs level with that at 83.2%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

Against the route

YX 3653 next to SDF to ORD

Every carrier on SDF to ORD combined arrived on time 79.0% of the time across 2,807 flights, so YX 3653 is 4 points ahead of it. Republic flew 1,736 flights on the same city pair under all its flight numbers, including this one, and those ran 82.5% on time. Across its whole network Republic Airways managed 78.5%, which this flight beats by 5 points.

YX 3653 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
YX 3653thin sample	303	83.2%	73 min	1.98%	B
All Republic Airways on SDF–ORD	1,736	82.5%	67 min	2.71%	B
All carriers on SDF–ORD	2,807	79.0%	78 min	2.81%	B
Republic Airways, whole network	361,482	78.5%	72 min	4.08%	B−

Across the year

YX 3653 quarter by quarter

YX 3653 did not run the same all year. Its best quarter was Jul–Sep 2025 at 87.8% on time and its weakest Jan–Mar 2026 at 75.3%, a swing of 13 points on roughly 101 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 flights87.8%
Oct–Dec 202592 flights85.4%
Jan–Mar 202690 flights75.3%
Apr–Jun 202629 flights—

Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, YX 3653 did best on Saturday at 90.5% on time and worst on Friday at 74.4%. Each day rests on about 43 flights, so a gap of 16 points is worth noticing but could still narrow in another year.

Delay causes

Why YX 3653 runs late

One category carries most of the weight here. National Airspace System accounts for 66% of the 3,663 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.

National Airspace System
66%
Carrier
17%
Late-arriving aircraft
13%
Extreme weather
5%

66% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 2,412 minutes out of 3,663, against a national NAS share of 21%. The split is drawn from 3,663 delay minutes reported on YX 3653.

Cancellations sit at 1.98% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

5.7% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.

Every one of the 303 flights under YX 3653 in the data flew SDF to ORD. The number was not reused on any other city pair, which makes this a clean record of one route.

One caution: this is a thin sample. 303 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 3653

For a booking, read YX 3653 as 83.2% on time with 1.98% cancelled over 303 flights. Those are rates from the past twelve months, not a forecast for any particular day.

Where to go next

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.

Key figures