Flight number record
DL 1389
Delta Air Lines · Houston to Detroit
- Route
- IAH → DTW
- Departs
- 05:20
- Flights
- 365
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s DL 1389, check with Delta Air Lines.
DL 1389 earns an A. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 12 points better than the national rate of 77.6%. When something does go wrong the average delay runs an hour and a half. That rests on 365 flights, with a median arrival 10 minutes early.
Set against the rest of the country, DL 1389's record is 12 points better than the US average of 77.6%. That gap is worth roughly 124 fewer late arrivals for every thousand flights.
Key figures
On time
90.0%
Arrivals under 15 minutes late, of 360 completed flights
Avg delay
97 min
Across delayed arrivals only, not all flights
Cancelled
1.37%
National rate is 1.81%
1 hour+ late
2.8%
National rate is 8.1%
These figures cover 365 flights between July 2025 and June 2026. The median arrival is 10 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 DL 1389 flies
DL 1389 flies IAH to DTW without a single fixed slot. Its most common scheduled departure was 05:20, used on 169 of 365 flights, with 05:30 (116 flights) and 05:15 (44 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 05:20169 flights46.3%
- Departs 05:30116 flights31.8%
- Departs 05:1544 flights12.1%
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 05:20 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and DL 1389 runs level with that at 90.0%. 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
DL 1389 next to IAH to DTW
Every carrier on IAH to DTW combined arrived on time 78.8% of the time across 2,137 flights, so DL 1389 is 11 points ahead of it. Delta flew 1,322 flights on the same city pair under all its flight numbers, including this one, and those ran 82.3% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 8 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DL 1389 | 365 | 90.0% | 97 min | 1.37% | A |
| All Delta Air Lines on IAH–DTW | 1,322 | 82.3% | 76 min | 0.76% | B+ |
| All carriers on IAH–DTW | 2,137 | 78.8% | 73 min | 1.22% | B |
| Delta Air Lines, whole network | 1,038,570 | 81.6% | 71 min | 1.62% | B |
Across the year
DL 1389 quarter by quarter
DL 1389 did not run the same all year. Its best quarter was Apr–Jun 2026 at 95.6% on time and its weakest Jan–Mar 2026 at 81.6%, a swing of 14 points on roughly 91 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 flights89.1%
- Oct–Dec 202592 flights93.3%
- Jan–Mar 202690 flights81.6%
- Apr–Jun 202691 flights95.6%
Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.
By weekday, DL 1389 ranged from 86.5% on Saturday to 94.2% on Wednesday. With about 52 flights behind each day, a spread of 8 points is inside normal variation, so the day you fly is not worth changing for this flight.
Delay causes
Why DL 1389 runs late
One category carries most of the weight here. Carrier accounts for 89% of the 3,508 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.
- 89%Carrier
- 10%National Airspace System
- 1%Extreme weather
- 0%Late-arriving aircraft
The largest share of delay minutes, 89%, 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 3,121 of the 3,508 delay minutes reported here. The split is drawn from 3,508 delay minutes reported on DL 1389.
Cancellations sit at 1.37% against a national 1.81%, which is ordinary. Diversions add another 0.00%.
Connections and routes
What a delay on this flight costs
Badly late arrivals are rare here: only 2.8% 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.
The 1,075 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.
Every one of the 365 flights under DL 1389 in the data flew IAH to DTW. 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. 365 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 DL 1389
For a booking, DL 1389 has one of the better records a US domestic flight can show: 90.0% on time and 1.37% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- IAH to DTW, every carrier and departure
- DTW to IAH, the return direction
- Delta Air Lines 1043 on the same route84.0%
- George Bush Intercontinental (IAH) delay statistics
- Detroit Metropolitan Wayne County (DTW) delay statistics
- Delta Air Lines on-time record
- Every Delta Air Lines flight number with a record
- The most and least reliable flight numbers in the US
- Worst months to fly in the US, ranked by the data
A flight number here means Delta Air Lines’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.