sensors Mode-S transponder

A3A0CF

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N33289 · BOEING 737-800 · operated by UNITED AIRLINES INC

Hex
A3A0CF
Octal
50720317
Decimal
10,723,535
Country
US
Tail
N33289
Type
B738
Broadcasting now · callsign UAL249 · 37,000 ft
Flights observed
230
Distinct callsigns
20
Country
US
Last broadcast
1h ago

Current position

A3A0CF is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A3A0CF 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

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-30 UAL249 CLT → EWR May 30, 06:45 UTCMay 30, 07:45 UTC1h 0m
2026-05-30 UAL1580 ORD → YVR May 30, 01:25 UTCMay 30, 05:10 UTC3h 45m
2026-05-29 UAL2821 HNL → EWR May 29, 21:20 UTCMay 29, 23:10 UTC1h 50m
2026-05-29 UAL2807 ORD → ORF May 29, 17:20 UTCMay 29, 18:55 UTC1h 35m
2026-05-29 UAL1902 IAH → GUA May 29, 15:20 UTCMay 29, 15:40 UTC20m
2026-05-29 UAL1902 IAH → GUA May 29, 13:35 UTCMay 29, 15:04 UTC1h 29m
2026-05-29 UAL1902 IAH → GUA May 29, 13:25 UTCMay 29, 15:40 UTC2h 15m
2026-05-28 UAL334 BOS → EWR May 28, 21:35 UTCMay 29, 01:00 UTC3h 25m
2026-05-28 UAL382 IAH → SAT May 28, 17:15 UTCMay 28, 20:10 UTC2h 55m
2026-05-28 UAL2140 SFO → IAH May 28, 13:45 UTCMay 28, 16:10 UTC2h 25m
2026-05-28 UAL631 IAH → BWI May 28, 07:00 UTCMay 28, 11:10 UTC4h 10m
2026-05-28 UAL1359 IAH → EWR May 28, 01:15 UTCMay 28, 05:15 UTC4h 0m
2026-05-27 UAL1696 SFO → RNO May 27, 21:10 UTCMay 27, 23:35 UTC2h 25m
2026-05-27 UAL2188 DEN → FLL May 27, 16:08 UTCMay 27, 19:41 UTC3h 33m
2026-05-27 UAL2188 DEN → FLL May 27, 16:05 UTCMay 27, 19:45 UTC3h 40m
2026-05-27 UAL1188 RDM → DEN May 27, 12:10 UTCMay 27, 14:15 UTC2h 5m
2026-05-27 UAL1588 EWR → SAV May 27, 02:55 UTCMay 27, 04:39 UTC1h 44m
2026-05-26 UAL1787 SFO → DEN May 26, 23:25 UTCMay 27, 01:44 UTC2h 20m
2026-05-26 UAL2455 EWR → ATL May 26, 19:40 UTCMay 26, 21:40 UTC2h 0m
2026-05-26 UAL2455 EWR → ATL May 26, 19:46 UTCMay 26, 21:38 UTC1h 52m
2026-05-26 UAL644 LAX → EWR May 26, 12:10 UTCMay 26, 15:45 UTC3h 35m
2026-05-26 UAL1510 IAD → PHX May 26, 00:24 UTCMay 26, 03:30 UTC3h 5m
2026-05-25 UAL2338 PSP → SFO May 25, 20:34 UTCMay 25, 22:30 UTC1h 55m
2026-05-25 UAL2368 SFO → DEN May 25, 17:10 UTCMay 25, 18:50 UTC1h 40m
2026-05-25 UAL2270 LAS → IAH May 25, 12:05 UTCMay 25, 15:40 UTC3h 35m
2026-05-24 UAL680 SAT → DEN May 24, 20:55 UTCMay 25, 04:05 UTC7h 10m
2026-05-24 UAL295 DEN → GEG May 24, 17:55 UTCMay 24, 19:55 UTC2h 0m
2026-05-24 UAL2307 DEN → LIH May 24, 15:00 UTCMay 24, 16:15 UTC1h 15m
2026-05-24 UAL1184 IAH → MSY May 24, 00:05 UTCMay 24, 01:10 UTC1h 5m
2026-05-23 UAL478 DEN → ORD May 23, 20:30 UTCMay 23, 21:35 UTC1h 5m
2026-05-23 UAL703 DEN → BIL May 23, 18:05 UTCMay 23, 19:15 UTC1h 11m
2026-05-23 UAL1727 LAS → SFO May 23, 13:20 UTCMay 23, 16:30 UTC3h 10m
2026-05-23 UAL248 BOS → IAH May 23, 00:10 UTCMay 23, 02:50 UTC2h 39m
2026-05-23 UAL248 BOS → IAH May 23, 00:04 UTCMay 23, 02:43 UTC2h 39m
2026-05-22 UAL479 CVG → DEN May 22, 20:20 UTCMay 22, 22:45 UTC2h 25m
2026-05-22 UAL1978 EWR → SFO May 22, 16:05 UTCMay 22, 18:20 UTC2h 15m
2026-05-22 UAL2771 HNL → ORD May 22, 12:15 UTCMay 22, 14:15 UTC2h 0m
2026-05-22 UAL1371 SNA → ORD May 22, 02:20 UTCMay 22, 04:35 UTC2h 15m
2026-05-21 UAL323 EWR → ORD May 21, 19:30 UTCMay 21, 23:40 UTC4h 10m
2026-05-21 UAL786 ATL → EWR May 21, 16:24 UTCMay 21, 17:38 UTC1h 14m
2026-05-21 UAL786 ATL → EWR May 21, 16:10 UTCMay 21, 17:40 UTC1h 30m
2026-05-21 UAL1113 ORD → MSP May 21, 12:55 UTCMay 21, 13:30 UTC35m
2026-05-21 UAL2090 IAH → PHL May 21, 03:15 UTCMay 21, 03:40 UTC25m
2026-05-20 UAL1990 LAX → EWR May 20, 23:45 UTCMay 21, 01:50 UTC2h 5m
2026-05-20 UAL622 LAX → ORD May 20, 19:50 UTCMay 20, 22:00 UTC2h 10m
2026-05-20 UAL2306 ORD → BOS May 20, 14:20 UTCMay 20, 17:55 UTC3h 35m
2026-05-19 UAL2325 ORD → PHL May 19, 21:50 UTCMay 20, 01:40 UTC3h 50m
2026-05-19 UAL204 BOS → IAD May 19, 18:25 UTCMay 19, 19:25 UTC1h 0m
2026-05-19 UAL1719 ORD → SFO May 19, 16:05 UTCMay 19, 16:50 UTC45m
2026-05-19 UAL2488 DEN → PHL May 19, 12:15 UTCMay 19, 14:15 UTC2h 0m

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 N33289 page for operator, model, and routing details .

Mode-S A3A0CF frequently asked

What is Mode-S code A3A0CF?
A3A0CF is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N33289.
Where is Mode-S A3A0CF registered?
Mode-S code A3A0CF 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 A3A0CF broadcasting right now?
Yes. Mode-S A3A0CF is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A3A0CF, octal 50720317, decimal 10,723,535.
What flights does A3A0CF operate?
Mode-S A3A0CF has broadcast 20 distinct callsigns, including UAL694, UAL248, UAL645, UAL2446, UAL730.