Flight number record

DL 1247

Delta Air Lines · Chicago to Atlanta

Route: ORD → ATL
Departs: 06:45
Flights: 361
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 1247, check with Delta Air Lines.

DL 1247 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 10 points better than the national rate of 77.6%. When something does go wrong the average delay runs close to two hours. That rests on 361 flights, with a median arrival 13 minutes early.

Set against the rest of the country, DL 1247's record is 10 points better than the US average of 77.6%. That gap is worth roughly 96 fewer late arrivals for every thousand flights.

On time

87.2%

Arrivals under 15 minutes late, of 358 completed flights

Avg delay

106 min

Across delayed arrivals only, not all flights

Cancelled

0.83%

National rate is 1.81%

1 hour+ late

5.3%

National rate is 8.1%

These figures cover 361 flights between July 2025 and June 2026. The median arrival is 13 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 1247 flies

DL 1247 flies ORD to ATL without a single fixed slot. Its most common scheduled departure was 06:45, used on 120 of 361 flights, with 07:05 (72 flights) and 07:10 (61 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 06:45120 flights33.2%
Departs 07:0572 flights19.9%
Departs 07:1061 flights16.9%

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 06:45 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and DL 1247 runs 2 points worse at 87.2%. 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 1247 next to ORD to ATL

Every carrier on ORD to ATL combined arrived on time 75.0% of the time across 6,409 flights, so DL 1247 is 12 points ahead of it. Delta flew 2,623 flights on the same city pair under all its flight numbers, including this one, and those ran 80.4% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 6 points.

DL 1247 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 1247thin sample	361	87.2%	106 min	0.83%	A+
All Delta Air Lines on ORD–ATL	2,623	80.4%	87 min	2.36%	B
All carriers on ORD–ATL	6,409	75.0%	81 min	2.26%	B
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 1247 quarter by quarter

Quarter by quarter DL 1247 held fairly steady: 88.5% in Jul–Sep 2025, 87.0% in Oct–Dec 2025, 82.0% in Jan–Mar 2026 and 91.1% 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 202588 flights88.5%
Oct–Dec 202592 flights87.0%
Jan–Mar 202690 flights82.0%
Apr–Jun 202691 flights91.1%

Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, DL 1247 did best on Tuesday at 96.2% on time and worst on Wednesday at 80.4%. 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 1247 runs late

One category carries most of the weight here. Carrier accounts for 68% of the 4,892 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
68%
National Airspace System
20%
Late-arriving aircraft
9%
Extreme weather
3%

The largest share of delay minutes, 68%, 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 3,344 of the 4,892 delay minutes reported here. The split is drawn from 4,892 delay minutes reported on DL 1247.

Cancellations are rare at 0.83%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

Connections and routes

What a delay on this flight costs

5.3% 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 close to two hours, which a normal layover absorbs.

The 606 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 361 flights under DL 1247 in the data flew ORD 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. 361 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 1247

For a booking, DL 1247 has one of the better records a US domestic flight can show: 87.2% on time and 0.83% 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