Flight number record
DL 1428
Delta Air Lines · New York to Miami
- Route
- JFK → MIA
- Departs
- 19:55
- Flights
- 352
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s DL 1428, check with Delta Air Lines.
DL 1428 sits in the middle of the pack with a C−. About seven flights in ten arrive on time by the DOT's definition, 9 points worse than the national rate of 77.6%. The late ones land an hour and a half behind schedule. That rests on 352 flights, with a median arrival 5 minutes early.
The national on-time rate over the same period is 77.6%, so DL 1428 runs 9 points behind the country as a whole. Across a thousand flights that is about 94 extra late arrivals.
Key figures
On time
68.2%
Arrivals under 15 minutes late, of 337 completed flights
Avg delay
96 min
Across delayed arrivals only, not all flights
Cancelled
4.26%
National rate is 1.81%
1 hour+ late
14.8%
National rate is 8.1%
These figures cover 352 flights between July 2025 and June 2026. Beyond the headline rate, 14.8% 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.
Schedule
When DL 1428 flies
DL 1428 flies JFK to MIA without a single fixed slot. Its most common scheduled departure was 19:55, used on 135 of 352 flights, with 19:59 (127 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 19:55135 flights38.4%
- Departs 19:59127 flights36.1%
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 19:55 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.2%, and DL 1428 runs level with that at 68.2%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
Against the route
DL 1428 next to JFK to MIA
Every carrier on JFK to MIA combined arrived on time 77.3% of the time across 4,553 flights, so DL 1428 is 9 points behind it. Delta flew 1,620 flights on the same city pair under all its flight numbers, including this one, and those ran 76.1% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 13 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DL 1428thin sample | 352 | 68.2% | 96 min | 4.26% | C− |
| All Delta Air Lines on JFK–MIA | 1,620 | 76.1% | 74 min | 3.21% | B− |
| All carriers on JFK–MIA | 4,553 | 77.3% | 93 min | 2.88% | B |
| Delta Air Lines, whole network | 1,038,570 | 81.6% | 71 min | 1.62% | B |
Across the year
DL 1428 quarter by quarter
DL 1428 did not run the same all year. Its best quarter was Apr–Jun 2026 at 78.0% on time and its weakest Jul–Sep 2025 at 60.9%, a swing of 17 points on roughly 88 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 flights60.9%
- Oct–Dec 202590 flights63.5%
- Jan–Mar 202679 flights70.3%
- Apr–Jun 202691 flights78.0%
Scale runs 50% to 85%. Rows with fewer than 30 flights show a dash.
By weekday, DL 1428 did best on Tuesday at 82.6% on time and worst on Sunday at 51.1%. Each day rests on about 50 flights, so a gap of 31 points is worth noticing but could still narrow in another year.
Delay causes
Why DL 1428 runs late
One category carries most of the weight here. Carrier accounts for 47% of the 10,000 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.
- 47%Carrier
- 27%Late-arriving aircraft
- 25%National Airspace System
- 1%Extreme weather
The largest share of delay minutes, 47%, 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 4,825 of the 10,000 delay minutes reported here. The split is drawn from 10,224 delay minutes reported on DL 1428.
Cancellations run at 4.26%, against 1.81% nationally. That is about one flight in 25 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and routes
What a delay on this flight costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 14.8% 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.
The 1,089 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 352 flights under DL 1428 in the data flew JFK to MIA. 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. 352 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 1428
For a booking, the cancellation rate is the figure to plan around on DL 1428: 4.26% of its 352 scheduled flights did not operate. A late arrival costs an hour and a half, but a cancellation costs the day, so leave a later option open.
Related
Where to go next
- JFK to MIA, every carrier and departure
- MIA to JFK, the return direction
- American Airlines 2017 on the same route86.0%
- Delta Air Lines 1514 on the same route79.2%
- Delta Air Lines 1528 on the same route84.2%
- Frontier Airlines 1809 on the same route79.4%
- American Airlines 688 on the same route77.6%
- John F. Kennedy International (JFK) delay statistics
- Miami International (MIA) 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
- The best time of day to fly, according to 7.04 million flight records
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.