Flight number record

DL 340

Delta Air Lines · Seattle to Kailua-Kona

Route: SEA → KOA
Departs: 14:20
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 340, check with Delta Air Lines.

DL 340 lands a B, about a point 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 about 50 minutes on average. That is a workable record, not a spotless one. That rests on 365 flights, with a median arrival 7 minutes early.

On time

78.5%

Arrivals under 15 minutes late, of 358 completed flights

Avg delay

51 min

Across delayed arrivals only, not all flights

Cancelled

1.64%

National rate is 1.81%

1 hour+ late

5.6%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. The median arrival is 7 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 340 flies

DL 340 flies SEA to KOA without a single fixed slot. Its most common scheduled departure was 14:20, used on 131 of 365 flights, with 14:30 (55 flights) and 15:25 (48 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 14:20131 flights35.9%
Departs 14:3055 flights15.1%
Departs 15:2548 flights13.2%

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 14:20 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and DL 340 runs 6 points better at 78.5%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

DL 340 next to SEA to KOA

Every carrier on SEA to KOA combined arrived on time 72.8% of the time across 1,421 flights, so DL 340 is 6 points ahead of it. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 3 points.

DL 340 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 340	365	78.5%	51 min	1.64%	B
All Delta Air Lines on SEA–KOA	365	78.5%	51 min	1.64%	B
All carriers on SEA–KOA	1,421	72.8%	51 min	1.13%	C
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 340 quarter by quarter

DL 340 did not run the same all year. Its best quarter was Jul–Sep 2025 at 84.8% on time and its weakest Jan–Mar 2026 at 65.5%, a swing of 19 points on roughly 91 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 flights84.8%
Oct–Dec 202592 flights78.4%
Jan–Mar 202690 flights65.5%
Apr–Jun 202691 flights84.6%

Scale runs 55% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, DL 340 did best on Wednesday at 90.2% on time and worst on Friday at 65.3%. Each day rests on about 52 flights, so a gap of 25 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 340 runs late

Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 3,924 reported delay minutes.

Carrier
41%
National Airspace System
39%
Late-arriving aircraft
20%

The largest share of delay minutes, 41%, 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 1,624 of the 3,924 delay minutes reported here. The split is drawn from 3,924 delay minutes reported on DL 340.

Cancellations sit at 1.64% against a national 1.81%, which is ordinary. Diversions add another 0.27%.

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 50 minutes, which a normal layover absorbs.

At 2,688 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.

The same number turns up on one other city pair in the data, including KOA to SEA (17), but none flew often enough under DL 340 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SEA to KOA only.

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 340

For a booking, read DL 340 as 78.5% on time with 1.64% cancelled over 365 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