Carrier route record
OOIAD→DTW
SkyWest Airlines · Washington to Detroit
- Flights
- 754
- Period
- July 2025 to June 2026
- Share of route
- 69%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with SkyWest Airlines.
SkyWest on IAD to DTW sits in the middle of the pack with a B. Close to three flights in four arrive on time by the DOT's definition, 2 points worse than the national rate of 77.6%. The late ones land close to two hours behind schedule. That rests on 754 flights, with a median arrival 8 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate SkyWest on IAD to DTW from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
75.5%
Arrivals under 15 minutes late, of 743 completed flights
Avg delay
124 min
Across delayed arrivals only, not all flights
Cancelled
1.33%
National rate is 1.81%
Whole route
76.7%
Every carrier on IAD to DTW, 1,096 flights
These figures cover 754 flights between July 2025 and June 2026. Beyond the headline rate, 13.3% 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
SkyWest against every carrier on IAD to DTW
SkyWest flew 754 of the 1,096 flights on IAD to DTW, most of the route. Its 75.5% on time is about level with the route as a whole at 76.7%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from Delta at 81.5% to SkyWest at 75.5%. Three 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.
| 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 Airwaysthin sample | 209 | 78.3% | 57 min | 2.39% | B |
| SkyWest Airlines (this page) | 754 | 75.5% | 124 min | 1.33% | B |
Departure window
When SkyWest runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 25 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–8am278 flights84.2%
- 8am–11am83 flights88.0%
- 11am–2pm129 flights74.2%
- 2pm–5pm—
- 5pm–8pm264 flights62.9%
- 8pm–5am—
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 62.9% on time, against 88.0% for the 8am–11am 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 5am–8am window is the busiest, with 278 flights scheduled in it.
Across the year
SkyWest on IAD to DTW through the year
December is the weak month at 38.7% on time, against 93.7% in May. 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. March was the busiest month here, with 86 flights.
Across the week, Thursday is the strongest day at 83.0% on time and Monday the weakest at 71.6%. 11 points is a smaller lever than departure hour, but it is free.
Delay causes
Why SkyWest runs late on this route
One category carries most of the weight here. Carrier accounts for 79% of the 23,000 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.
- 79%Carrier
- 10%Extreme weather
- 9%National Airspace System
- 2%Security
The largest share of delay minutes, 79%, 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 18,000 of the 23,000 delay minutes reported here. The split is drawn from 22,649 reported delay minutes.
Cancellations sit at 1.33% against a national 1.81%, which is ordinary. Diversions add another 0.13%.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 13.3% 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 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 8am–11am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 68.5% on time across 754 flights, 7 points below 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 7 points of difference.
One caution: this is a thin sample. 754 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 SkyWest on IAD to DTW
Put together: treat all of this as provisional. 754 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 75.5% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 743 completed flights over 12 months sit behind that.
Related
Where to go next
- IAD to DTW, every carrier
- SkyWest on DTW to IAD, the return leg
- Republic Airways on IAD to DTW78.3%
- SkyWest Airlines network-wide record
- Washington Dulles International (IAD) delay statistics
- Detroit Metropolitan Wayne County (DTW) delay statistics
- How often a connection fails at the major US hubs
- The best time of day to fly, according to 7.04 million flight records
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.