Flight number record

DL 3140

Delta Air Lines · Dayton to Atlanta

Route: DAY → ATL
Departs: 06:00
Flights: 349
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 3140, check with Delta Air Lines.

DL 3140 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 13 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 349 flights, with a median arrival 16 minutes early.

Set against the rest of the country, DL 3140's record is 13 points better than the US average of 77.6%. That gap is worth roughly 133 fewer late arrivals for every thousand flights.

On time

90.9%

Arrivals under 15 minutes late, of 342 completed flights

Avg delay

121 min

Across delayed arrivals only, not all flights

Cancelled

2.01%

National rate is 1.81%

1 hour+ late

4.7%

National rate is 8.1%

These figures cover 349 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 3140 flies

DL 3140 is scheduled to leave Dayton (DAY) at 06:00 local time and reach Atlanta (ATL) at 07:45. That slot held for 306 of the 349 scheduled departures in the data, so the figures below describe one steady operation rather than a number that moved around the clock.

Departs 06:00306 flights87.7%

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 3140 runs level with that at 90.9%. 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 3140 next to DAY to ATL

Every carrier on DAY to ATL combined arrived on time 89.7% of the time across 1,400 flights, so DL 3140 is about level with it. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 9 points.

DL 3140 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 3140thin sample	349	90.9%	121 min	2.01%	A
All Delta Air Lines on DAY–ATL	1,400	89.7%	101 min	1.71%	A
All carriers on DAY–ATL	1,400	89.7%	101 min	1.71%	A
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 3140 quarter by quarter

Quarter by quarter DL 3140 held fairly steady: 90.2% in Jul–Sep 2025, 92.4% in Oct–Dec 2025, 91.4% in Jan–Mar 2026 and 90.0% in Apr–Jun 2026. A spread of 2 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights90.2%
Oct–Dec 202580 flights92.4%
Jan–Mar 202686 flights91.4%
Apr–Jun 202691 flights90.0%

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

By weekday, DL 3140 ranged from 86.0% on Wednesday to 96.0% on Thursday. With about 50 flights behind each day, a spread of 10 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why DL 3140 runs late

One category carries most of the weight here. Carrier accounts for 71% of the 3,755 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
71%
Late-arriving aircraft
16%
National Airspace System
7%
Extreme weather
7%

The largest share of delay minutes, 71%, 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 2,659 of the 3,755 delay minutes reported here. The split is drawn from 3,755 delay minutes reported on DL 3140.

Cancellations sit at 2.01% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 4.7% 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 349 flights under DL 3140 in the data flew DAY 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. 349 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 3140

For a booking, read DL 3140 as 90.9% on time with 2.01% cancelled over 349 flights. Those are rates from the past twelve months, not a forecast for any particular 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