Flight number record

DL 935

Delta Air Lines · Detroit to Salt Lake City

Route: DTW → SLC
Departs: 12:15
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 935, check with Delta Air Lines.

DL 935 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 about 40 minutes. That rests on 365 flights, with a median arrival 5 minutes early.

Set against the rest of the country, DL 935's record is 10 points better than the US average of 77.6%. That gap is worth roughly 95 fewer late arrivals for every thousand flights.

On time

87.1%

Arrivals under 15 minutes late, of 365 completed flights

Avg delay

40 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

1 hour+ late

2.2%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. The median arrival is 5 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 935 flies

DL 935 flies DTW to SLC without a single fixed slot. Its most common scheduled departure was 12:15, used on 195 of 365 flights, with 12:20 (55 flights) and 12:30 (52 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 12:15195 flights53.4%
Departs 12:2055 flights15.1%
Departs 12:3052 flights14.2%

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 12:15 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.8%, and DL 935 runs 8 points better at 87.1%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

DL 935 next to DTW to SLC

Every carrier on DTW to SLC combined arrived on time 80.4% of the time across 1,574 flights, so DL 935 is 7 points ahead of it. Delta flew 1,546 flights on the same city pair under all its flight numbers, including this one, and those ran 80.0% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 6 points.

DL 935 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 935	365	87.1%	40 min	0.00%	A+
All Delta Air Lines on DTW–SLC	1,546	80.0%	59 min	0.19%	B+
All carriers on DTW–SLC	1,574	80.4%	59 min	0.19%	B+
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 935 quarter by quarter

DL 935 did not run the same all year. Its best quarter was Jul–Sep 2025 at 91.3% on time and its weakest Oct–Dec 2025 at 80.4%, a swing of 11 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 flights91.3%
Oct–Dec 202592 flights80.4%
Jan–Mar 202690 flights87.8%
Apr–Jun 202691 flights89.0%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, DL 935 did best on Friday at 94.2% on time and worst on Wednesday at 78.8%. Each day rests on about 52 flights, so a gap of 15 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 935 runs late

One category carries most of the weight here. Carrier accounts for 53% of the 1,894 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
53%
National Airspace System
27%
Late-arriving aircraft
14%
Extreme weather
5%

The largest share of delay minutes, 53%, 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 1,008 of the 1,894 delay minutes reported here. The split is drawn from 1,894 delay minutes reported on DL 935.

Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 2.2% 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.

The 1,481 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 365 flights under DL 935 in the data flew DTW to SLC. 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. 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 935

For a booking, DL 935 has one of the better records a US domestic flight can show: 87.1% on time and 0.00% 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