About 1 in 11 DL 3973 flights from Salt Lake City arrived 15+ minutes late, diverted or cancelled over the past year (9%); 0.5% were cancelled. The typical flight landed 11 minutes early.
DL 3973: SLC → SUN
Scheduled to leave Salt Lake City at 10:45 a.m. local time, operated by SkyWest as OO 3973. Over the past year it arrived on time 91% of the time (361 flights), in line with other DL flights on the route at that hour (91%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 53 | 96% |
| Tuesday | 51 | 98% |
| Wednesday | 51 | 86% |
| Thursday | 50 | 88% |
| Friday | 52 | 88% |
| Saturday | 52 | 90% |
| Sunday | 52 | 88% |
Why it was late
All flights SLC → SUN · Connecting off DL 3973? Check the risk
Questions
How often is DL 3973 from SLC to SUN late?
Delta Air Lines 3973 from Salt Lake City, UT to Sun Valley/Hailey/Ketchum, ID arrived 15 or more minutes late, was diverted or was cancelled on 9% of 361 scheduled flights between September 2025 and August 2026. 0.5% were cancelled.
Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Delta Air Lines for today's flight. Method.