Flight number record

DL 991

Delta Air Lines · Los Angeles to New York

Route: LAX → JFK
Departs: 13:15
Flights: 337
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 991, check with Delta Air Lines.

DL 991 lands a B, 2 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by close to two hours on average. That is a workable record, not a spotless one. That rests on 337 flights, with a median arrival 10 minutes early.

On time

79.1%

Arrivals under 15 minutes late, of 330 completed flights

Avg delay

121 min

Across delayed arrivals only, not all flights

Cancelled

1.48%

National rate is 1.81%

1 hour+ late

8.8%

National rate is 8.1%

These figures cover 337 flights between July 2025 and June 2026. Beyond the headline rate, 8.8% 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 991 flies

DL 991 flies LAX to JFK without a single fixed slot. Its most common scheduled departure was 13:15, used on 47 of 337 flights, with 13:30 (41 flights) and 16:00 (40 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 13:1547 flights13.9%
Departs 13:3041 flights12.2%
Departs 16:0040 flights11.9%

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 13:15 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.8%, and DL 991 runs level with that at 79.1%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

DL 991 next to LAX to JFK

Every carrier on LAX to JFK combined arrived on time 79.1% of the time across 10,287 flights, so DL 991 is about level with it. Delta flew 3,358 flights on the same city pair under all its flight numbers, including this one, and those ran 81.6% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 3 points.

DL 991 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 991thin sample	337	79.1%	121 min	1.48%	B
All Delta Air Lines on LAX–JFK	3,358	81.6%	93 min	1.79%	B
All carriers on LAX–JFK	10,287	79.1%	92 min	2.04%	B
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 991 quarter by quarter

DL 991 did not run the same all year. Its best quarter was Apr–Jun 2026 at 84.7% on time and its weakest Jan–Mar 2026 at 67.5%, a swing of 17 points on roughly 84 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 flights82.4%
Oct–Dec 202588 flights81.6%
Jan–Mar 202683 flights67.5%
Apr–Jun 202674 flights84.7%

Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, DL 991 did best on Tuesday at 91.8% on time and worst on Monday at 67.4%. Each day rests on about 48 flights, so a gap of 24 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 991 runs late

One category carries most of the weight here. Carrier accounts for 58% of the 8,318 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
58%
National Airspace System
24%
Late-arriving aircraft
18%
Extreme weather
0%

The largest share of delay minutes, 58%, 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 4,789 of the 8,318 delay minutes reported here. The split is drawn from 8,318 delay minutes reported on DL 991.

Cancellations sit at 1.48% against a national 1.81%, which is ordinary. Diversions add another 0.59%.

Connections and routes

What a delay on this flight costs

8.8% 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.

At 2,475 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.

Every one of the 337 flights under DL 991 in the data flew LAX to JFK. 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. 337 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 991

For a booking, read DL 991 as 79.1% on time with 1.48% cancelled over 337 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