sensors Mode-S transponder

A43EEC

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N37297 · operated by UNITED AIRLINES INC

Hex
A43EEC
Octal
51037354
Decimal
10,764,012
Country
US
Tail
N37297
Type
B38M
Broadcasting now · callsign UAL1009 · 37,000 ft
Flights observed
386
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 16:15 UTC

Current position

A43EEC is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A43EEC 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
UAL1901 United Airlines 8 2026-06-06
UAL1645 United Airlines 7 2026-05-22
UAL2252 United Airlines 6 2026-07-22
UAL1137 United Airlines 6 2026-06-06
UAL1063 United Airlines 5 2026-07-22
UAL643 - 4 2026-07-10
UAL2661 United Airlines 4 2026-04-14
UAL234 United Airlines 4 2026-04-17
UAL2184 United Airlines 4 2026-06-04
UAL2035 United Airlines 4 2026-07-25
UAL2010 United Airlines 4 2026-07-26
UAL1251 United Airlines 4 2026-05-12
UAL841 - 3 2026-06-15
UAL406 - 3 2026-07-17
UAL363 United Airlines 3 2026-06-14
UAL2409 - 3 2026-07-15
UAL2172 United Airlines 3 2026-07-17
UAL2080 United Airlines 3 2026-06-08
UAL1942 United Airlines 3 2026-05-10
UAL1934 United Airlines 3 2026-04-21

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 UAL2010 LAX → SEA Jul 26, 15:35 UTCJul 26, 16:15 UTC40m
2026-07-25 UAL2035 LAX → SFO Jul 25, 22:20 UTCJul 26, 04:15 UTC5h 55m
2026-07-25 UAL2035 LAX → SFO Jul 25, 22:19 UTCJul 26, 04:11 UTC5h 52m
2026-07-25 UAL1207 EWR → JAX Jul 25, 15:25 UTCJul 25, 20:25 UTC5h 0m
2026-07-25 UAL1207 EWR → JAX Jul 25, 15:32 UTCJul 25, 20:27 UTC4h 55m
2026-07-25 UAL1685 LIH → DEN Jul 25, 12:55 UTCJul 25, 13:40 UTC45m
2026-07-25 UAL1684 SFO → LIH Jul 25, 01:10 UTCJul 25, 01:50 UTC40m
2026-07-25 UAL1684 SFO → LIH Jul 25, 01:16 UTCJul 25, 06:26 UTC5h 10m
2026-07-24 UAL1763 SFO → AUS Jul 24, 22:50 UTCJul 24, 23:55 UTC1h 5m
2026-07-24 UAL1626 ORD → DEN Jul 24, 14:17 UTCJul 24, 19:05 UTC4h 48m
2026-07-24 UAL1626 ORD → DEN Jul 24, 14:00 UTCJul 24, 19:10 UTC5h 10m
2026-07-24 UAL601 BOS → EWR Jul 24, 11:28 UTCJul 24, 12:30 UTC1h 2m
2026-07-24 UAL1611 LAX → SFO Jul 24, 03:10 UTCJul 24, 04:15 UTC1h 5m
2026-07-23 UAL1317 EWR → IAH Jul 23, 21:35 UTCJul 24, 01:50 UTC4h 15m
2026-07-23 UAL446 MCO → EWR Jul 23, 15:15 UTCJul 23, 20:15 UTC5h 0m
2026-07-23 UAL648 EWR → SFO Jul 23, 11:05 UTCJul 23, 12:55 UTC1h 50m
2026-07-23 UAL1527 ORD → LAS Jul 23, 03:20 UTCJul 23, 05:25 UTC2h 5m
2026-07-22 UAL2252 MEX → EWR Jul 22, 19:30 UTCJul 23, 00:00 UTC4h 30m
2026-07-22 UAL2252 MEX → EWR Jul 22, 19:13 UTCJul 22, 23:57 UTC4h 44m
2026-07-22 UAL1063 EWR → MEX Jul 22, 12:47 UTCJul 22, 17:03 UTC4h 16m
2026-07-22 UAL1063 EWR → MEX Jul 22, 12:45 UTCJul 22, 17:00 UTC4h 15m
2026-07-21 UAL2036 SJU → EWR Jul 21, 01:35 UTCJul 21, 02:35 UTC1h 0m
2026-07-20 UAL2036 SJU → EWR Jul 20, 23:00 UTCJul 20, 23:15 UTC15m
2026-07-20 UAL1339 LAX → DEN Jul 20, 21:20 UTCJul 20, 21:40 UTC20m
2026-07-20 UAL1339 LAX → DEN Jul 20, 16:20 UTCJul 20, 19:50 UTC3h 30m
2026-07-20 UAL1584 - Jul 20, 13:30 UTCJul 20, 13:50 UTC20m
2026-07-20 UAL2859 - Jul 20, 02:15 UTCJul 20, 02:30 UTC15m
2026-07-19 UAL1698 SFO → SLC Jul 19, 18:55 UTCJul 19, 23:40 UTC4h 45m
2026-07-19 UAL1514 EWR → PUJ Jul 19, 12:49 UTCJul 19, 16:09 UTC3h 20m
2026-07-19 UAL1514 - Jul 19, 12:55 UTCJul 19, 13:50 UTC55m
2026-07-18 UAL1143 EUG → SFO Jul 18, 20:20 UTCJul 19, 00:30 UTC4h 10m
2026-07-18 UAL1143 EUG → SFO Jul 18, 19:30 UTCJul 19, 00:29 UTC4h 59m
2026-07-18 UAL1142 DCA → ORD Jul 18, 14:39 UTCJul 18, 18:19 UTC3h 40m
2026-07-18 UAL1142 DCA → ORD Jul 18, 14:35 UTCJul 18, 18:00 UTC3h 25m
2026-07-18 UAL554 EWR → DFW Jul 18, 00:35 UTCJul 18, 01:00 UTC25m
2026-07-18 UAL554 EWR → DFW Jul 18, 00:22 UTCJul 18, 01:39 UTC1h 17m
2026-07-17 UAL2172 IAH → PHL Jul 17, 20:25 UTCJul 17, 21:25 UTC1h 0m
2026-07-17 UAL1975 LAS → EWR Jul 17, 14:24 UTCJul 17, 19:00 UTC4h 35m
2026-07-17 UAL406 - Jul 17, 06:00 UTCJul 17, 07:20 UTC1h 20m
2026-07-17 UAL406 SFO → LAS Jul 17, 06:03 UTCJul 17, 07:17 UTC1h 14m
2026-07-16 UAL1769 - Jul 16, 22:49 UTCJul 17, 03:59 UTC5h 10m
2026-07-16 UAL1205 - Jul 16, 15:30 UTCJul 16, 20:09 UTC4h 40m
2026-07-16 UAL1750 - Jul 16, 11:34 UTCJul 16, 12:30 UTC55m
2026-07-16 UAL1750 OGG → SFO Jul 16, 08:06 UTCJul 16, 12:27 UTC4h 21m
2026-07-16 UAL1749 - Jul 16, 01:20 UTCJul 16, 01:50 UTC30m
2026-07-15 UAL2409 YYC → SFO Jul 15, 20:35 UTCJul 15, 23:10 UTC2h 35m
2026-07-15 UAL2409 YYC → SFO Jul 15, 20:29 UTCJul 15, 23:08 UTC2h 39m
2026-07-15 UAL2830 SFO → YYC Jul 15, 16:10 UTCJul 15, 18:10 UTC2h 0m
2026-07-15 UAL1301 DEN → SFO Jul 15, 12:18 UTCJul 15, 14:15 UTC1h 57m
2026-07-15 UAL1301 - Jul 15, 12:05 UTCJul 15, 14:20 UTC2h 15m

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 N37297 page for operator, model, and routing details .

Mode-S A43EEC frequently asked

What is Mode-S code A43EEC?
A43EEC is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N37297.
Where is Mode-S A43EEC registered?
Mode-S code A43EEC 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 A43EEC broadcasting right now?
Yes. Mode-S A43EEC is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A43EEC, octal 51037354, decimal 10,764,012.
What flights does A43EEC operate?
Mode-S A43EEC has broadcast 20 distinct callsigns, including UAL1901, UAL1645, UAL2252, UAL1137, UAL1063.