Flight number record

DL 717

Delta Air Lines · San Francisco to Detroit

Route: SFO → DTW
Departs: 14:40
Flights: 254
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 717, check with Delta Air Lines.

DL 717 sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 7 points worse than the national rate of 77.6%. The late ones land roughly 50 minutes behind schedule. That rests on 254 flights, with a median arrival 3 minutes early.

The national on-time rate over the same period is 77.6%, so DL 717 runs 7 points behind the country as a whole. Across a thousand flights that is about 68 extra late arrivals.

On time

70.8%

Arrivals under 15 minutes late, of 250 completed flights

Avg delay

48 min

Across delayed arrivals only, not all flights

Cancelled

1.18%

National rate is 1.81%

1 hour+ late

6.8%

National rate is 8.1%

These figures cover 254 flights between July 2025 and June 2026. The median arrival is 3 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 717 flies

DL 717 flies SFO to DTW without a single fixed slot. Its most common scheduled departure was 14:40, used on 79 of 254 flights, with 14:35 (35 flights) and 14:50 (31 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 14:4079 flights31.1%
Departs 14:3535 flights13.8%
Departs 14:5031 flights12.2%

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 14:40 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and DL 717 runs level with that at 70.8%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

DL 717 next to SFO to DTW

Every carrier on SFO to DTW combined arrived on time 79.4% of the time across 1,797 flights, so DL 717 is 9 points behind it. Delta flew 1,388 flights on the same city pair under all its flight numbers, including this one, and those ran 78.2% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 11 points.

DL 717 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 717thin sample	254	70.8%	48 min	1.18%	C
All Delta Air Lines on SFO–DTW	1,388	78.2%	53 min	0.86%	B+
All carriers on SFO–DTW	1,797	79.4%	53 min	0.83%	B+
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 717 quarter by quarter

DL 717 did not run the same all year. Its best quarter was Oct–Dec 2025 at 80.3% on time and its weakest Apr–Jun 2026 at 47.4%, a swing of 33 points on roughly 85 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 202586 flights80.2%
Oct–Dec 202567 flights80.3%
Jan–Mar 202621 flights—
Apr–Jun 202680 flights47.4%

Scale runs 40% to 85%. Rows with fewer than 30 flights show a dash.

By weekday, DL 717 did best on Tuesday at 84.6% on time and worst on Wednesday at 62.2%. Each day rests on about 36 flights, so a gap of 22 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 717 runs late

One category carries most of the weight here. Late-arriving aircraft accounts for 54% of the 3,465 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.

Late-arriving aircraft
54%
Carrier
27%
National Airspace System
19%

54% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 3,465 reported delay minutes here, that single category outweighs weather by 54 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 3,465 delay minutes reported on DL 717.

Cancellations sit at 1.18% against a national 1.81%, which is ordinary. Diversions add another 0.39%.

Connections and routes

What a delay on this flight costs

6.8% 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 roughly 50 minutes, which a normal layover absorbs.

At 2,079 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 two other city pairs in the data, including CHA to ATL (38) and SAV to ATL (16), but none flew often enough under DL 717 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SFO to DTW only.

One caution: this is a thin sample. 254 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 717

For a booking, DL 717 is one of the weaker ways to fly SFO to DTW: 9 points below the route as a whole. If the schedule allows, compare it with the other departures listed on the route page before settling on this one.

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