Flight Reliability
DL 4004 · Delta Air Lines
RDM → Salt Lake City (RDM–SLC)99% of its flights flew this route. The rest (SEA–PDX) are included in these numbers.
- 89%
- Arrive within 15 minutes
- 6 min
- Average arrival delay
- 1.8%
- Cancelled
- 14 min early
- Median arrival delay
Based on 171 historical flights. Data through May 2026.
What the data says
The 3–6 AM departure wins.
DL 4004 departing between 3–6 AM arrived on time 90% of the time, versus 83% between 6–9 AM.
Skip Wednesday if you can.
DL 4004 arrived on time 96% of the time on Thursdays. On Wednesdays: 83%.
Better than the Delta Air Lines network average.
DL 4004 arrived on time 89% of the time, versus 81% across the Delta Air Lines network.
Trending in the right direction.
DL 4004 arrived on time 96% of the time over the last three months in the data, compared with 77% in the three months before that.
The breakdown
- Mon87%(23 flights)
- Tue84%(25 flights)
- Wed83%(24 flights)
- Thu96%(24 flights)
- Fri91%(23 flights)
- Sat88%(25 flights)
- Sun92%(24 flights)
- 3–6 AM90%(144 flights)
- 6–9 AM83%(23 flights)
- 6–9 PM—(1 flights)
Dec 67% → May 97% on time
| Month | On-time percentage | Flights |
|---|---|---|
| December 2025 | 67% | 12 |
| January 2026 | 81% | 31 |
| February 2026 | 84% | 25 |
| March 2026 | 94% | 31 |
| April 2026 | 97% | 30 |
| May 2026 | 97% | 31 |
- Departures on time
- 89%
- Diverted
- 0%
- Flights flown
- 168
- Months covered
- 8
Same route, other flights
Keep nerding
Based on 171 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.