Flight number record

DL 847

Delta Air Lines · Salt Lake City to Washington

Route: SLC → IAD
Departs: 17:35
Flights: 364
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 847, check with Delta Air Lines.

DL 847 earns an A. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 8 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 364 flights, with a median arrival 8 minutes early.

Set against the rest of the country, DL 847's record is 8 points better than the US average of 77.6%. That gap is worth roughly 84 fewer late arrivals for every thousand flights.

On time

86.0%

Arrivals under 15 minutes late, of 358 completed flights

Avg delay

63 min

Across delayed arrivals only, not all flights

Cancelled

1.65%

National rate is 1.81%

1 hour+ late

5.9%

National rate is 8.1%

These figures cover 364 flights between July 2025 and June 2026. The median arrival is 8 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 847 flies

DL 847 flies SLC to IAD without a single fixed slot. Its most common scheduled departure was 17:35, used on 87 of 364 flights, with 17:55 (62 flights) and 17:50 (59 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 17:3587 flights23.9%
Departs 17:5562 flights17.0%
Departs 17:5059 flights16.2%

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 17:35 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.2%, and DL 847 runs 18 points better at 86.0%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.

Against the route

DL 847 next to SLC to IAD

Every carrier on SLC to IAD combined arrived on time 87.5% of the time across 713 flights, so DL 847 is 2 points behind it. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 4 points.

DL 847 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 847thin sample	364	86.0%	63 min	1.65%	A
All Delta Air Lines on SLC–IADthin sample	364	86.0%	63 min	1.65%	A
All carriers on SLC–IAD	713	87.5%	66 min	1.26%	A
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 847 quarter by quarter

Quarter by quarter DL 847 held fairly steady: 83.7% in Jul–Sep 2025, 88.9% in Oct–Dec 2025, 84.7% in Jan–Mar 2026 and 86.8% in Apr–Jun 2026. A spread of 5 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights83.7%
Oct–Dec 202591 flights88.9%
Jan–Mar 202690 flights84.7%
Apr–Jun 202691 flights86.8%

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

By weekday, DL 847 did best on Tuesday at 94.2% on time and worst on Sunday at 78.0%. 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 847 runs late

One category carries most of the weight here. Carrier accounts for 62% of the 3,160 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
62%
Late-arriving aircraft
22%
National Airspace System
11%
Extreme weather
4%

The largest share of delay minutes, 62%, 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 1,974 of the 3,160 delay minutes reported here. The split is drawn from 3,160 delay minutes reported on DL 847.

Cancellations sit at 1.65% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

5.9% 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 an hour, which a normal layover absorbs.

At 1,827 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 364 flights under DL 847 in the data flew SLC to IAD. 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. 364 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 847

For a booking, read DL 847 as 86.0% on time with 1.65% cancelled over 364 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