UAL2121

Flight

Status

Completed

Arrival confirmed via

ADS-B (ground reading)

Departure

Denver International Airport (DEN) — Denver, United States

Departed

2026-09-25 00:16 UTC

Arrival

Gerald R. Ford International Airport (GRR) — Grand Rapids, United States

Distance flown

1638 km

Straight-line distance

1629 km

Approach distance

63 km

Aircraft

Registration

N17441

Type

Boeing 737 MAX 9

Seats

179 total (117 Economy, 42 Economy Plus, 20 First) (typical for type, not this tail)

Altitude & speed

Max altitude

29,025 ft

Max ground speed

484 kt

Tracked

2h 23m · 1,635 km

Altitude (ft, max 29,025)

Ground speed (kt, max 484)

Altitude (ft, max 29,025)

Ground speed (kt, max 484)

From the ADS-B positions we received; time since the first fix. A dashed stretch is a gap in reception, bridged by a straight line.

Route map

Airline

United Airlines (UAL)

Latest flights

Departed	Flight	Route	Reg	Aircraft	Status	Distance
2026-10-02 23:56 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N77426	Boeing 737 MAX 9	In progress	~1629 km est.
2026-10-02 00:03 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N17594	Boeing 737-900	Completed	1717 km
2026-10-01 00:06 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	B737-M9	Boeing 737 MAX 9	Completed	1726 km
2026-09-29 23:47 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N17429	Boeing 737 MAX 9	Completed	1659 km
2026-09-29 00:09 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N17452	Boeing 737 MAX 9	Completed	1677 km
2026-09-28 00:36 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N34455	Boeing 737-900	Completed	1692 km
2026-09-27 00:17 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N17438	Boeing 737 MAX 9	Completed	1639 km
2026-09-26 06:40 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N37577	Boeing 737 MAX 9	Completed	1637 km
2026-09-25 00:16 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N17441	Boeing 737 MAX 9	Completed	1638 km
2026-09-24 00:15 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N67845	Boeing 737-900	Completed	1639 km
2026-09-23 00:04 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N69830	Boeing 737-900	Completed	1637 km
2026-09-22 00:04 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N38446	Boeing 737-900	Completed	1636 km
2026-09-21 01:37 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N75435	Boeing 737-900	Completed	1638 km
2026-09-20 00:10 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68821	Boeing 737-900	Completed	1823 km
2026-09-19 00:48 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68821	Boeing 737-900	Completed	1809 km
2026-09-18 01:40 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68891	Boeing 737-900	Completed	1723 km
2026-09-17 00:52 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N36444	Boeing 737-900	Completed	1711 km
2026-09-16 00:21 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68842	Boeing 737-900	Completed	1739 km
2026-09-15 00:08 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68802	Boeing 737-900	Completed	1840 km
2026-09-14 00:27 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68817	Boeing 737-900	Completed	1775 km
2026-09-12 23:53 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N62884	Boeing 737-900	Completed	1759 km
2026-09-11 23:54 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N62883	Boeing 737-900	Completed	1784 km
2026-09-10 23:48 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N75433	Boeing 737-900	Completed	1794 km
2026-09-10 00:04 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N37427	Boeing 737-900	Completed	1780 km
2026-09-07 23:54 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N28457	Boeing 737-900	Completed	1753 km
2026-09-07 00:31 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N78448	Boeing 737-900	Completed	1813 km
2026-09-06 00:25 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N53442	Boeing 737-900	Completed	1695 km
2026-09-05 00:04 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N69888	Boeing 737-900	Completed	1643 km
2026-09-04 01:08 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N69847	Boeing 737-900	Completed	1711 km
2026-09-02 23:59 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N39416	Boeing 737-900	Completed	1728 km
2026-09-02 00:03 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68843	Boeing 737-900	Completed	1756 km
2026-09-01 00:13 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N69830	Boeing 737-900	Completed	1742 km
2026-08-31 00:47 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68891	Boeing 737-900	Completed	1753 km
2026-08-30 00:11 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N37555	Boeing 737 MAX 9	Completed	1772 km
2026-08-29 00:07 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N27477	Boeing 737-900	Completed	1874 km
2026-08-27 23:50 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N37419	Boeing 737-900	Completed	1861 km
2026-08-26 23:55 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N27477	Boeing 737-900	Completed	1737 km
2026-08-25 23:58 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N69804	Boeing 737-900	Completed	1741 km
2026-08-25 00:39 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N69813	Boeing 737-900	Completed	1818 km
2026-08-24 01:29 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N62892	Boeing 737-900	Completed	1682 km
2026-08-23 03:36 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N39461	Boeing 737-900	Completed	2717 km
2026-08-22 00:11 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N37462	Boeing 737-900	Completed	2677 km
2026-08-21 00:11 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N69835	Boeing 737-900	Completed	2125 km
2026-08-20 00:04 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68823	Boeing 737-900	Completed	2458 km
2026-08-18 23:59 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N38417	Boeing 737-900	Completed	2521 km
2026-08-17 23:56 UTC	UAL2121	DEN → ? Denver → ?	N38417	Boeing 737-900	Incomplete (signal lost)	2210 km
2026-08-17 00:05 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68891	Boeing 737-900	Completed (landing presumed)	2555 km
2026-08-16 02:08 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N36447	Boeing 737-900	Completed	2899 km
2026-08-14 04:12 UTC	UAL2121	DEN → GRR Denver → Grand Rapids	N68802	Boeing 737-900	Completed	1884 km
2026-08-14 01:22 UTC	UAL2121	BOI → DEN Boise → Denver	N68802	Boeing 737-900	Completed	1296 km