Flight number record
DL 1228
Delta Air Lines · Detroit to Atlanta
- Route
- DTW → ATL
- Departs
- 12:21
- Flights
- 335
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s DL 1228, check with Delta Air Lines.
DL 1228 lands a B, 3 points better than the national rate of 77.6%. About one flight in five 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 335 flights, with a median arrival 5 minutes early.
Key figures
On time
81.0%
Arrivals under 15 minutes late, of 331 completed flights
Avg delay
72 min
Across delayed arrivals only, not all flights
Cancelled
1.19%
National rate is 1.81%
1 hour+ late
6.0%
National rate is 8.1%
These figures cover 335 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.
Schedule
When DL 1228 flies
DL 1228 flies DTW to ATL without a single fixed slot. Its most common scheduled departure was 12:21, used on 61 of 335 flights, with 14:59 (35 flights) and 15:05 (35 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 12:2161 flights18.2%
- Departs 14:5935 flights10.4%
- Departs 15:0535 flights10.4%
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 12:21 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.8%, and DL 1228 runs 2 points better at 81.0%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
Against the route
DL 1228 next to DTW to ATL
Every carrier on DTW to ATL combined arrived on time 79.0% of the time across 4,881 flights, so DL 1228 is 2 points ahead of it. Delta flew 3,703 flights on the same city pair under all its flight numbers, including this one, and those ran 81.6% on time. Across its whole network Delta Air Lines managed 81.6%, close to this flight's figure.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DL 1228thin sample | 335 | 81.0% | 72 min | 1.19% | B |
| All Delta Air Lines on DTW–ATL | 3,703 | 81.6% | 68 min | 0.49% | B+ |
| All carriers on DTW–ATL | 4,881 | 79.0% | 75 min | 0.80% | B+ |
| Delta Air Lines, whole network | 1,038,570 | 81.6% | 71 min | 1.62% | B |
Across the year
DL 1228 quarter by quarter
DL 1228 did not run the same all year. Its best quarter was Jul–Sep 2025 at 88.0% on time and its weakest Oct–Dec 2025 at 77.8%, a swing of 10 points on roughly 84 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 flights88.0%
- Oct–Dec 202592 flights77.8%
- Jan–Mar 202689 flights78.2%
- Apr–Jun 202662 flights79.0%
Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.
By weekday, DL 1228 did best on Thursday at 91.7% on time and worst on Sunday at 73.9%. Each day rests on about 48 flights, so a gap of 18 points is worth noticing but could still narrow in another year.
Delay causes
Why DL 1228 runs late
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 4,503 reported delay minutes.
- 36%Late-arriving aircraft
- 34%Carrier
- 21%National Airspace System
- 9%Extreme weather
36% 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 4,503 reported delay minutes here, that single category outweighs weather by 4 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 4,503 delay minutes reported on DL 1228.
Cancellations sit at 1.19% against a national 1.81%, which is ordinary. Diversions add another 0.00%.
Connections and routes
What a delay on this flight costs
6.0% 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.
The 594 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 one other city pair in the data, including LAS to SEA (1), but none flew often enough under DL 1228 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to DTW to ATL only.
One caution: this is a thin sample. 335 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 1228
For a booking, read DL 1228 as 81.0% on time with 1.19% cancelled over 335 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- DTW to ATL, every carrier and departure
- ATL to DTW, the return direction
- Delta Air Lines 2856 on the same route86.3%
- Delta Air Lines 1611 on the same route86.9%
- Delta Air Lines 1467 on the same route76.3%
- Delta Air Lines 2375 on the same route90.3%
- Delta Air Lines 2053 on the same route73.9%
- Delta Air Lines 965 on the same route86.4%
- Detroit Metropolitan Wayne County (DTW) delay statistics
- Hartsfield-Jackson Atlanta International (ATL) 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
- Why the first flight of the morning is statistically safest
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.