Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A449A1

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N37560 · BOEING 737 MAX 9 · operated by UNITED AIRLINES INC

Hex
A449A1
Octal
51044641
Decimal
10,766,753
Country
US
Tail
N37560
Type
B39M
No current signal · last broadcast 3h ago
Flights observed
224
Distinct callsigns
20
Country
US
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S A449A1.

Country allocation

The ICAO 24-bit address A449A1 falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States receives a permanent address from this block at the time of registration; the address stays with the airframe even if the aircraft is re-registered to a different operator within the country.

Callsign history 20 distinct

Callsign Airline Flights Last seen
UAL641 United Airlines 4 2026-06-11
UAL2360 United Airlines 4 2026-05-28
UAL1167 United Airlines 4 2026-05-25
UAL1136 United Airlines 4 2026-05-25
UAL2400 United Airlines 3 2026-05-05
UAL2356 - 3 2026-06-12
UAL1724 United Airlines 3 2026-05-08
UAL1718 United Airlines 3 2026-05-07
UAL638 United Airlines 2 2026-05-01
UAL595 United Airlines 2 2026-05-26
UAL594 United Airlines 2 2026-05-10
UAL574 United Airlines 2 2026-06-01
UAL505 United Airlines 2 2026-04-21
UAL399 United Airlines 2 2026-05-15
UAL392 United Airlines 2 2026-05-23
UAL3886 United Airlines 2 2026-04-19
UAL2740 United Airlines 2 2026-05-20
UAL2680 United Airlines 2 2026-04-23
UAL2661 United Airlines 2 2026-06-12
UAL2398 United Airlines 2 2026-06-10

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-06-12 UAL2356 SFO → BOS Jun 12, 18:50 UTCJun 12, 23:35 UTC4h 45m
2026-06-12 UAL2661 PHL → ORD Jun 12, 11:00 UTCJun 12, 16:45 UTC5h 45m
2026-06-12 UAL2619 DEN → MSP Jun 12, 00:05 UTCJun 12, 05:10 UTC5h 6m
2026-06-11 UAL1074 BOS → SFO Jun 11, 15:50 UTCJun 11, 21:45 UTC5h 55m
2026-06-11 UAL641 IAD → BOS Jun 11, 12:53 UTCJun 11, 14:11 UTC1h 18m
2026-06-11 UAL641 IAD → BOS Jun 11, 12:55 UTCJun 11, 14:10 UTC1h 15m
2026-06-11 UAL564 BOS → ORD Jun 11, 05:40 UTCJun 11, 10:00 UTC4h 20m
2026-06-11 UAL2429 BDL → ORD Jun 11, 01:50 UTCJun 11, 03:45 UTC1h 55m
2026-06-10 UAL2409 PHL → ORD Jun 10, 21:45 UTCJun 11, 00:05 UTC2h 20m
2026-06-10 UAL2459 DEN → YYC Jun 10, 17:55 UTCJun 10, 20:00 UTC2h 5m
2026-06-10 UAL1219 ATL → DEN Jun 10, 13:05 UTCJun 10, 16:00 UTC2h 55m
2026-06-10 UAL1219 ATL → DEN Jun 10, 13:12 UTCJun 10, 15:58 UTC2h 46m
2026-06-10 UAL2398 IAD → EWR Jun 10, 00:05 UTCJun 10, 01:05 UTC1h 0m
2026-06-09 UAL681 NAS → EWR Jun 9, 19:10 UTCJun 9, 21:25 UTC2h 15m
2026-06-09 UAL1480 EWR → NAS Jun 9, 14:42 UTCJun 9, 16:35 UTC1h 53m
2026-06-09 UAL1480 EWR → NAS Jun 9, 14:25 UTCJun 9, 15:50 UTC1h 25m
2026-06-09 UAL601 BOS → EWR Jun 9, 11:20 UTCJun 9, 12:25 UTC1h 5m
2026-06-09 UAL2131 PBI → EWR Jun 9, 02:30 UTCJun 9, 03:15 UTC45m
2026-06-08 UAL2131 PBI → EWR Jun 8, 20:15 UTCJun 9, 00:45 UTC4h 30m
2026-06-08 UAL2101 PBI → EWR Jun 8, 13:21 UTCJun 8, 18:13 UTC4h 52m
2026-06-08 UAL2101 PBI → EWR Jun 8, 13:15 UTCJun 8, 18:15 UTC5h 0m
2026-06-08 UAL1252 EWR → MIA Jun 8, 10:10 UTCJun 8, 11:00 UTC50m
2026-06-08 UAL2398 IAD → EWR Jun 8, 00:25 UTCJun 8, 01:25 UTC1h 0m
2026-06-07 UAL1287 SFO → BOS Jun 7, 17:35 UTCJun 7, 21:35 UTC4h 0m
2026-06-07 UAL1435 SFO → IAH Jun 7, 11:25 UTCJun 7, 15:50 UTC4h 25m
2026-06-06 UAL1595 BZE → EWR Jun 6, 21:35 UTCJun 7, 01:24 UTC3h 50m
2026-06-06 UAL1595 BZE → EWR Jun 6, 21:21 UTCJun 7, 01:24 UTC4h 3m
2026-06-06 UAL2134 DEN → BZE Jun 6, 16:04 UTCJun 6, 19:40 UTC3h 35m
2026-06-06 UAL2325 ORD → PHL Jun 6, 00:35 UTCJun 6, 14:09 UTC13h 35m
2026-06-05 UAL1263 MSN → ORD Jun 5, 20:35 UTCJun 5, 22:25 UTC1h 50m
2026-06-05 UAL2661 PHL → ORD Jun 5, 17:55 UTCJun 5, 18:50 UTC55m
2026-06-05 UAL2441 TPA → EWR Jun 5, 10:10 UTCJun 5, 16:15 UTC6h 5m
2026-06-05 UAL1800 SNA → IAH Jun 5, 01:15 UTCJun 5, 03:05 UTC1h 50m
2026-06-04 UAL308 ATL → EWR Jun 4, 21:20 UTCJun 4, 22:55 UTC1h 35m
2026-06-04 UAL2182 PDX → SFO Jun 4, 16:55 UTCJun 4, 18:30 UTC1h 35m
2026-06-04 UAL2182 PDX → SFO Jun 4, 17:02 UTCJun 4, 18:27 UTC1h 25m
2026-06-04 UAL2668 OMA → ORD Jun 4, 12:05 UTCJun 4, 14:25 UTC2h 20m
2026-06-02 UAL2777 EWR → TPA Jun 2, 19:15 UTCJun 2, 21:35 UTC2h 20m
2026-06-02 UAL1988 IAH → CLT Jun 2, 14:30 UTCJun 2, 17:00 UTC2h 30m
2026-06-01 UAL1020 IAD → EWR Jun 1, 22:35 UTCJun 1, 22:55 UTC20m
2026-06-01 UAL1020 IAD → EWR Jun 1, 22:39 UTCJun 2, 00:20 UTC1h 41m
2026-06-01 UAL1711 SFO → CLE Jun 1, 17:50 UTCJun 1, 20:20 UTC2h 30m
2026-06-01 UAL574 LAS → SFO Jun 1, 12:50 UTCJun 1, 16:20 UTC3h 30m
2026-06-01 UAL1210 EWR → ATL Jun 1, 01:00 UTCJun 1, 03:55 UTC2h 55m
2026-05-31 UAL1254 PSP → SFO May 31, 22:05 UTCMay 31, 23:35 UTC1h 30m
2026-05-31 UAL1102 MSN → EWR May 31, 17:25 UTCMay 31, 19:40 UTC2h 15m
2026-05-31 UAL1981 DEN → LGA May 31, 12:45 UTCMay 31, 13:20 UTC35m
2026-05-31 UAL2753 LAX → SFO May 31, 08:25 UTCMay 31, 10:45 UTC2h 20m
2026-05-31 UAL1730 IAD → SEA May 31, 00:20 UTCMay 31, 01:11 UTC51m
2026-05-30 UAL2241 EWR → SAT May 30, 17:40 UTCMay 30, 22:30 UTC4h 50m

About Mode-S

A Mode-S transponder code (also called an "ICAO 24-bit address" or "hex code") is a 6-character hexadecimal identifier permanently assigned to an aircraft when it's first registered. Unlike callsigns (which change with each flight) or registrations (which can change if an aircraft is sold internationally), the Mode-S address stays with the airframe for the life of the aircraft in that country.

Every ADS-B transmission from an aircraft includes its Mode-S address, making it the most reliable way to identify a specific airframe. Flight-tracking services like Apparatus use the Mode-S address as the primary key for tying position broadcasts, callsigns, and ownership records together.

Prefer a tail-number view? See the N37560 page for operator, model, and routing details .

Mode-S A449A1 frequently asked

What is Mode-S code A449A1?
A449A1 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N37560.
Where is Mode-S A449A1 registered?
Mode-S code A449A1 is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is A449A1 broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A449A1, octal 51044641, decimal 10,766,753.
What flights does A449A1 operate?
Mode-S A449A1 has broadcast 20 distinct callsigns, including UAL641, UAL2360, UAL1167, UAL1136, UAL2400.