Flight number record

DL 1540

Delta Air Lines · Philadelphia to Detroit

Route: PHL → DTW
Departs: 06:00
Flights: 346
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 1540, check with Delta Air Lines.

DL 1540 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 14 points better than the national rate of 77.6%. When something does go wrong the average delay runs about 2.9 hours. That rests on 346 flights, with a median arrival 16 minutes early.

Set against the rest of the country, DL 1540's record is 14 points better than the US average of 77.6%. That gap is worth roughly 138 fewer late arrivals for every thousand flights.

On time

91.4%

Arrivals under 15 minutes late, of 337 completed flights

Avg delay

176 min

Across delayed arrivals only, not all flights

Cancelled

2.60%

National rate is 1.81%

1 hour+ late

5.6%

National rate is 8.1%

These figures cover 346 flights between July 2025 and June 2026. The median arrival is 16 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 1540 flies

DL 1540 flies PHL to DTW without a single fixed slot. Its most common scheduled departure was 06:00, used on 231 of 346 flights, with 06:05 (60 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 06:00231 flights66.8%
Departs 06:0560 flights17.3%

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 06:00 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and DL 1540 runs 2 points better at 91.4%. 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 1540 next to PHL to DTW

Every carrier on PHL to DTW combined arrived on time 79.8% of the time across 2,952 flights, so DL 1540 is 12 points ahead of it. Delta flew 1,557 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 10 points.

DL 1540 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 1540thin sample	346	91.4%	176 min	2.60%	A
All Delta Air Lines on PHL–DTW	1,557	82.3%	105 min	2.12%	B
All carriers on PHL–DTW	2,952	79.8%	96 min	3.05%	B−
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 1540 quarter by quarter

Quarter by quarter DL 1540 held fairly steady: 93.1% in Jul–Sep 2025, 91.2% in Oct–Dec 2025, 87.1% in Jan–Mar 2026 and 94.4% in Apr–Jun 2026. A spread of 7 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202573 flights93.1%
Oct–Dec 202592 flights91.2%
Jan–Mar 202690 flights87.1%
Apr–Jun 202691 flights94.4%

Scale runs 80% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, DL 1540 did best on Wednesday at 100.0% on time and worst on Tuesday at 87.5%. Each day rests on about 49 flights, so a gap of 13 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 1540 runs late

One category carries most of the weight here. Carrier accounts for 94% of the 5,108 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.

Carrier
94%
National Airspace System
4%
Extreme weather
1%

The largest share of delay minutes, 94%, 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 4,822 of the 5,108 delay minutes reported here. The split is drawn from 5,108 delay minutes reported on DL 1540.

Cancellations run at 2.60%, against 1.81% nationally. That is about one flight in 40 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

5.6% 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 2.9 hours, which a normal layover absorbs.

Every one of the 346 flights under DL 1540 in the data flew PHL 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. 346 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 1540

For a booking, the cancellation rate is the figure to plan around on DL 1540: 2.60% of its 346 scheduled flights did not operate. A late arrival costs about 2.9 hours, but a cancellation costs the day, so leave a later option open.

Where to go next

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.

Key figures