the record · airliner · Boeing 737-824 · flight page

N17233 flying as UAL1255

Level at 37,000 feet, 20 miles west of Kirksville Regional, heading east at 459 knots (528 mph).

Position from the receiver network, just now; local time 8:10 pm CST (02:10 UTC). This page checks for a newer position every half minute while it is open.

Took off DENDenver International, Denver, CO Today at 6:57 pm

Last heard …still in the air, or beyond the receivers' hearing Today at 8:10 pm

Length: 1 h 12 min
Distance: 543 nm (625 miles)
Top altitude: 37,000 ft
Fastest: 508 knots (585 mph)
Positions heard: 32

This flight is the one in progress (or the last one heard, if the aircraft flew beyond the receivers). Times are local to where the aircraft was.

Line colour: altitude Low 10,000 ft 25,000 ft 40,000 ft Start End

Altitude and speed through the flight

Move along the graph to read the altitude and speed at any moment.

Flights in the last 14 days

When	From	To	Length	Distance	Top altitude	Fastest
Today at 6:57 pm to 8:10 pm	Denver International DEN	still in the air, or out of the network's hearing	1 h 12 min	543 nm	37,000 ft	508 kt
Today at 2:52 pm to 3:16 pm	in the air when first heard	Denver International DEN	24 min	120 nm	25,000 ft	472 kt
Today at 12:40 pm to 1:10 pm	Denver International DEN	still in the air, or out of the network's hearing	30 min	153 nm	22,000 ft	359 kt
Today at 8:48 am to 10:52 am	John Wayne/Orange County SNA	Denver International DEN	2 h 3 min	788 nm	33,000 ft	520 kt
Yesterday at 9:43 pm to 11:17 pm	Denver International DEN	still in the air, or out of the network's hearing	1 h 34 min	598 nm	38,000 ft	445 kt
Yesterday at 4:06 pm to 6:25 pm	in the air when first heard	Denver International DEN	2 h 19 min	934 nm	36,000 ft	474 kt
Yesterday at 11:00 am to 1:07 pm	Denver International DEN	Nashville International BNA	2 h 6 min	904 nm	37,000 ft	500 kt
Yesterday at 7:43 am to 9:07 am	in the air when first heard	Denver International DEN	1 h 24 min	611 nm	37,000 ft	494 kt
Yesterday at 7:09 am to 7:14 am	Santa Barbara Municipal SBA	still in the air, or out of the network's hearing	4 min	15 nm	9,900 ft	315 kt
Sunday at 11:11 pm to 11:24 pm	in the air when first heard	Santa Barbara Municipal SBA	12 min	34 nm	14,075 ft	313 kt
Sunday at 9:09 pm to 10:40 pm	Denver International DEN	still in the air, or out of the network's hearing	1 h 31 min	596 nm	36,000 ft	427 kt
Sunday at 4:34 pm to 6:51 pm	in the air when first heard	Denver International DEN	2 h 17 min	842 nm	38,000 ft	427 kt
Sunday at 3:38 pm to 3:52 pm	in the air when first heard	still in the air, or out of the network's hearing	14 min	101 nm	34,000 ft	449 kt
Sunday at 1:39 pm to 2:02 pm	in the air when first heard	Savannah/Hilton Head International SAV	22 min	124 nm	33,000 ft	485 kt
Sunday at 11:17 am to 1:02 pm	Denver International DEN	still in the air, or out of the network's hearing	1 h 45 min	824 nm	37,000 ft	535 kt
Sunday at 7:34 am to 8:50 am	in the air when first heard	Denver International DEN	1 h 15 min	603 nm	41,000 ft	552 kt
Saturday at 8:44 pm to 10:13 pm	Denver International DEN	still in the air, or out of the network's hearing	1 h 29 min	572 nm	28,000 ft	427 kt
Saturday at 5:48 pm to 7:16 pm	Bozeman Yellowstone International BZN	Denver International DEN	1 h 28 min	512 nm	39,000 ft	445 kt
Saturday at 2:45 pm to 4:03 pm	Denver International DEN	Bozeman Yellowstone International BZN	1 h 18 min	487 nm	40,000 ft	452 kt
Saturday at 10:52 am to 12:52 pm	Mineta San Jose International SJC	Denver International DEN	1 h 59 min	884 nm	39,000 ft	541 kt
Friday at 9:35 pm to 11:57 pm	Denver International DEN	Mineta San Jose International SJC	2 h 21 min	840 nm	38,000 ft	425 kt
Friday at 6:54 pm to 8:16 pm	Phoenix Sky Harbor International PHX	Denver International DEN	1 h 21 min	539 nm	38,975 ft	489 kt
Friday at 3:50 pm to 5:00 pm	in the air when first heard	Phoenix Sky Harbor International PHX	1 h 9 min	359 nm	38,000 ft	456 kt
Friday at 11:59 am to 3:26 pm	Washington Dulles International IAD	still in the air, or out of the network's hearing	3 h 26 min	1,354 nm	38,000 ft	424 kt
Friday at 8:03 am to 10:15 am	in the air when first heard	Washington Dulles International IAD	2 h 12 min	855 nm	39,000 ft	477 kt
Thursday at 5:00 pm to 8:21 pm	Denver International DEN	Miami International MIA	3 h 20 min	1,535 nm	35,000 ft	506 kt
Thursday at 1:06 pm to 2:48 pm	Austin-Bergstrom International AUS	Denver International DEN	1 h 42 min	694 nm	36,000 ft	476 kt
Thursday at 9:06 am to 10:57 am	Denver International DEN	Austin-Bergstrom International AUS	1 h 50 min	702 nm	37,000 ft	447 kt

Show the last 56 days · A flight is a run of positions with no gap longer than twenty minutes; an airport is named when the aircraft was low and within five miles of it at that end.

Positions from the adsb.lol community network (open data). A distance is the sum of the straight lines between the positions heard, so it is a little short of the true track. Positions are kept in full for 7 days and at one point every five minutes after that, for 180 days. Map: OpenFreeMap, OpenMapTiles, OpenStreetMap contributors. For understanding where an aircraft went, not for flying.

The aircraft

Aircraft: Boeing 737-824, built 1999
Kind: Airliner, 149 seats
Operator: United Airlines INC
Registered in: Chicago, IL
Transponder code: A12378

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