Carrier route record

YXIAD→DTW

Republic Airways · Washington to Detroit

Flights: 209
Period: July 2025 to June 2026
Share of route: 19%
Carriers: 4

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Republic Airways.

Republic on IAD to DTW lands a B, level with the national rate of 77.6%. About one flight in five 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 209 flights, with a median arrival 5 minutes early.

The US average over the same twelve months is 77.6%, so there is little to separate Republic on IAD to DTW from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

78.3%

Arrivals under 15 minutes late, of 203 completed flights

Avg delay

57 min

Across delayed arrivals only, not all flights

Cancelled

2.39%

National rate is 1.81%

Whole route

76.7%

Every carrier on IAD to DTW, 1,096 flights

These figures cover 209 flights between July 2025 and June 2026. The median arrival is 5 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

Republic against every carrier on IAD to DTW

Republic flew 209 of the 1,096 flights on IAD to DTW, about 19% of it. Its 78.3% on time is 2 points better than the route as a whole, which runs 76.7%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from Delta at 81.5% to SkyWest at 75.5%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.

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.

On-time performance by carrier on IAD to DTW
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Linesthin sample	94	81.5%	77 min	2.13%	B
United Airlinesthin sample	39	79.5%	49 min	0.00%	B+
Republic Airways (this page)thin sample	209	78.3%	57 min	2.39%	B
SkyWest Airlines	754	75.5%	124 min	1.33%	B

Departure window

When Republic runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 16 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–11am13 flights—
11am–2pm41 flights90.0%
2pm–5pm—
5pm–8pm98 flights74.2%
8pm–5am57 flights73.6%

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

The best window here is not the first bank but the 11am–2pm slot at 90.0% on time, ahead of 8pm–5am at 73.6%. Where the curve peaks mid-day rather than at dawn, the constraint is usually congestion at one end rather than the aircraft's own rotation. The 5pm–8pm window is the busiest, with 98 flights scheduled in it.

Across the year

Republic on IAD to DTW through the year

Jul–Sep 202543 flights76.2%
Oct–Dec 202534 flights76.5%
Jan–Mar 202670 flights74.6%
Apr–Jun 202662 flights85.0%

Scale runs 65% to 90%. 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 78.3% on time across 209 flights.

Republic on IAD to DTW did not run the same all year. Its best quarter was Apr–Jun 2026 at 85.0% on time and its weakest Jan–Mar 2026 at 74.6%, a swing of 10 points on roughly 52 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, Thursday is the strongest day at 86.7% on time and Friday the weakest at 79.4%. 7 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Republic runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 45% of the 2,510 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.

Late-arriving aircraft
45%
National Airspace System
28%
Carrier
27%

45% 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 2,510 reported delay minutes here, that single category outweighs weather by 45 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 2,510 reported delay minutes.

Cancellations sit at 2.39% against a national 1.81%, which is ordinary. Diversions add another 0.48%.

Connections and stage length

What a delay here costs

7.4% 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 about an hour, which a normal layover absorbs.

At 383 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 11am–2pm window matters as much as it does.

The return leg is a different operation and performs like one: it runs 84.0% on time across 228 flights, 6 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 6 points of difference.

One caution: this is a thin sample. 209 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 Republic on IAD to DTW

Put together: treat all of this as provisional. 209 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 78.3% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 203 completed flights over 12 months sit behind that.

Where to go next

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