Flight history · Aug 2025 – Jul 2026 · US DOT on-time records
UA 1521 · Des Moines (DSM) → Denver (DEN)
Sold by United. Still flying: 56 of the last 56 days (Daily).
Arrives on time88%within 15 minutes, of 72 flights
Cancelled0.0%of scheduled flights
An hour or more late7%of flights that operated
When late, on average92 minlate, among flights 15+ min late
Schedule
Typical times in the Jun 6 – Jul 31, 2026 schedule, local at each airport (Denver is 1 h behind Des Moines).
- Leaves DSM
- 09:14
- Arrives DEN
- 10:20
- Flight time
- 2h 06m
- Days flown, last 8 weeks
- 56 of 56
Each square is a day, Sat Jun 6 to Fri Jul 31, two weeks per row (each column is the same weekday); filled = flew.
How late it arrives
Share of flights that operated arriving more than this late.
Horizontal: minutes late at arrival (0 to 3 hours). Vertical: share of flights later than that.
Its hour at DSM
All flights leaving Des Moines (DSM) at 9–10 am, wherever they’re going: 87% left within 15 minutes and 1.6% were cancelled (809 flights in the year). Other United flights on this route →
Upcoming forecasts
Our odds that this flight is late or cancelled on the days we publish.