Flight number record

DL 1524

Delta Air Lines · St. Louis to Atlanta

Route: STL → ATL
Departs: 06:00
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 1524, check with Delta Air Lines.

DL 1524 earns an A. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 16 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 15 minutes early.

Set against the rest of the country, DL 1524's record is 16 points better than the US average of 77.6%. That gap is worth roughly 163 fewer late arrivals for every thousand flights.

On time

93.9%

Arrivals under 15 minutes late, of 358 completed flights

Avg delay

88 min

Across delayed arrivals only, not all flights

Cancelled

1.37%

National rate is 1.81%

1 hour+ late

1.7%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. The median arrival is 15 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 1524 flies

DL 1524 is scheduled to leave St. Louis (STL) at 06:00 local time and reach Atlanta (ATL) at 08:38. That slot held for 337 of the 365 scheduled departures in the data, so the figures below describe one steady operation rather than a number that moved around the clock.

Departs 06:00337 flights92.3%

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 1524 runs 5 points better at 93.9%. 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 1524 next to STL to ATL

Every carrier on STL to ATL combined arrived on time 85.3% of the time across 3,705 flights, so DL 1524 is 9 points ahead of it. Delta flew 2,371 flights on the same city pair under all its flight numbers, including this one, and those ran 89.4% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 12 points.

DL 1524 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 1524	365	93.9%	88 min	1.37%	A
All Delta Air Lines on STL–ATL	2,371	89.4%	77 min	1.98%	A
All carriers on STL–ATL	3,705	85.3%	72 min	1.73%	A
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 1524 quarter by quarter

Quarter by quarter DL 1524 held fairly steady: 93.5% in Jul–Sep 2025, 97.8% in Oct–Dec 2025, 95.3% in Jan–Mar 2026 and 89.0% in Apr–Jun 2026. A spread of 9 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights93.5%
Oct–Dec 202592 flights97.8%
Jan–Mar 202690 flights95.3%
Apr–Jun 202691 flights89.0%

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

By weekday, DL 1524 did best on Friday at 100.0% on time and worst on Monday at 84.0%. Each day rests on about 52 flights, so a gap of 16 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 1524 runs late

One category carries most of the weight here. Carrier accounts for 66% of the 1,930 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
66%
Late-arriving aircraft
17%
National Airspace System
15%
Extreme weather
2%

The largest share of delay minutes, 66%, 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 1,277 of the 1,930 delay minutes reported here. The split is drawn from 1,930 delay minutes reported on DL 1524.

Cancellations sit at 1.37% against a national 1.81%, which is ordinary. Diversions add another 0.55%.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 1.7% 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.

Every one of the 365 flights under DL 1524 in the data flew STL to ATL. 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 1524

For a booking, DL 1524 has one of the better records a US domestic flight can show: 93.9% on time and 1.37% cancelled. That is a base rate, not a promise about any single day.

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