sensors Mode-S transponder

A5CF66

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N47357 · BOEING 737 MAX 8 · operated by UNITED AIRLINES INC

Hex
A5CF66
Octal
51347546
Decimal
10,866,534
Country
US
Tail
N47357
Type
B38M
No current signal · last broadcast 4h ago
Flights observed
205
Distinct callsigns
20
Country
US
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S A5CF66.

Country allocation

The ICAO 24-bit address A5CF66 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
2026-05-29 UAL1445 STT → IAD May 29, 20:50 UTCMay 29, 21:10 UTC20m
2026-05-29 UAL1908 IAH → STT May 29, 15:25 UTCMay 29, 19:25 UTC4h 1m
2026-05-29 UAL584 PHX → EWR May 29, 10:30 UTCMay 29, 13:30 UTC3h 0m
2026-05-28 UAL1663 LAS → EWR May 28, 23:35 UTCMay 29, 02:25 UTC2h 50m
2026-05-28 UAL1455 EWR → MIA May 28, 19:20 UTCMay 28, 21:35 UTC2h 15m
2026-05-28 UAL1454 IAH → NAS May 28, 15:20 UTCMay 28, 17:30 UTC2h 10m
2026-05-28 UAL1114 SFO → ORD May 28, 11:05 UTCMay 28, 13:55 UTC2h 50m
2026-05-27 UAL685 IAH → EWR May 27, 23:50 UTCMay 28, 02:00 UTC2h 10m
2026-05-27 UAL685 IAH → EWR May 27, 23:51 UTCMay 28, 02:00 UTC2h 9m
2026-05-27 UAL2208 FLL → EWR May 27, 17:45 UTCMay 27, 22:10 UTC4h 25m
2026-05-27 UAL1443 IAD → STT May 27, 15:35 UTCMay 27, 15:50 UTC15m
2026-05-27 UAL1443 IAD → STT May 27, 12:33 UTCMay 27, 15:59 UTC3h 26m
2026-05-27 UAL1443 IAD → STT May 27, 12:25 UTCMay 27, 13:05 UTC40m
2026-05-27 UAL572 ORD → MSN May 27, 04:22 UTCMay 27, 10:33 UTC6h 11m
2026-05-27 UAL572 ORD → MSN May 27, 04:09 UTCMay 27, 10:35 UTC6h 25m
2026-05-26 UAL280 DEN → ANC May 26, 18:14 UTCMay 26, 22:54 UTC4h 40m
2026-05-26 UAL1035 DCA → ORD May 26, 01:40 UTCMay 26, 03:55 UTC2h 15m
2026-05-25 UAL1883 SFO → SJD May 25, 22:10 UTCMay 26, 00:09 UTC2h 0m
2026-05-25 UAL1715 DEN → EWR May 25, 18:15 UTCMay 25, 20:30 UTC2h 15m
2026-05-25 UAL2271 LAX → SEA May 25, 14:20 UTCMay 25, 16:40 UTC2h 20m
2026-05-25 UAL361 DEN → BOS May 25, 10:55 UTCMay 25, 12:50 UTC1h 55m
2026-05-25 UAL1942 MSY → SFO May 25, 01:55 UTCMay 25, 03:15 UTC1h 20m
2026-05-24 UAL1918 LIR → DEN May 24, 23:00 UTCMay 24, 23:25 UTC25m
2026-05-24 UAL1876 EWR → LIR May 24, 11:55 UTCMay 24, 21:45 UTC9h 50m
2026-05-23 UAL1446 LIR → EWR May 23, 23:00 UTCMay 24, 03:15 UTC4h 15m
2026-05-23 UAL775 IAD → EWR May 23, 15:50 UTCMay 23, 19:15 UTC3h 26m
2026-05-23 UAL775 IAD → EWR May 23, 15:51 UTCMay 23, 20:49 UTC4h 58m
2026-05-23 UAL1138 GUA → LAX May 23, 08:45 UTCMay 23, 11:00 UTC2h 15m
2026-05-23 UAL1138 GUA → LAX May 23, 08:39 UTCMay 23, 13:28 UTC4h 49m
2026-05-23 UAL1138 GUA → LAX May 23, 08:39 UTCMay 23, 13:24 UTC4h 45m
2026-05-22 UAL1632 PDX → SFO May 22, 22:30 UTCMay 22, 22:45 UTC15m
2026-05-22 UAL1632 PDX → SFO May 22, 20:30 UTCMay 22, 20:50 UTC20m
2026-05-22 UAL700 BOS → EWR May 22, 15:00 UTCMay 22, 17:45 UTC2h 45m
2026-05-22 UAL700 BOS → EWR May 22, 15:00 UTCMay 22, 17:45 UTC2h 45m
2026-05-22 UAL725T IAH → SFO May 22, 03:00 UTCMay 22, 04:50 UTC1h 50m
2026-05-21 UAL1430 OGG → DEN May 21, 23:35 UTCMay 22, 01:40 UTC2h 5m
2026-05-21 UAL2313 ORD → IAH May 21, 07:00 UTCMay 21, 21:35 UTC14h 35m
2026-05-21 UAL1272 LAX → SFO May 21, 02:25 UTCMay 21, 04:35 UTC2h 10m
2026-05-21 UAL1272 LAX → SFO May 21, 00:25 UTCMay 21, 00:40 UTC15m
2026-05-20 UAL1271 SFO → MEX May 20, 22:40 UTCMay 20, 22:50 UTC10m
2026-05-20 UAL1271 SFO → MEX May 20, 19:10 UTCMay 20, 21:05 UTC1h 55m
2026-05-19 UAL1383 IAH → SFO May 19, 21:55 UTCMay 19, 23:05 UTC1h 10m
2026-05-19 UAL1172 BOS → SFO May 19, 17:20 UTCMay 19, 20:30 UTC3h 10m
2026-05-19 UAL2484 IAH → DFW May 19, 12:32 UTCMay 19, 14:50 UTC2h 18m
2026-05-19 UAL2484 IAH → DFW May 19, 01:40 UTCMay 19, 14:50 UTC13h 10m
2026-05-18 UAL284 AUS → EWR May 18, 21:30 UTCMay 18, 23:45 UTC2h 15m
2026-05-18 UAL323 EWR → ORD May 18, 17:40 UTCMay 18, 19:30 UTC1h 49m
2026-05-18 UAL1318 EWR → MSY May 18, 13:15 UTCMay 18, 15:25 UTC2h 10m
2026-05-18 UAL2078 BOS → ORD May 18, 01:25 UTCMay 18, 03:45 UTC2h 20m
2026-05-17 UAL1867 CZM → IAH May 17, 21:10 UTCMay 17, 23:20 UTC2h 10m

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 N47357 page for operator, model, and routing details .

Mode-S A5CF66 frequently asked

What is Mode-S code A5CF66?
A5CF66 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N47357.
Where is Mode-S A5CF66 registered?
Mode-S code A5CF66 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 A5CF66 broadcasting right now?
No active broadcast right now. Last signal was 4h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A5CF66, octal 51347546, decimal 10,866,534.
What flights does A5CF66 operate?
Mode-S A5CF66 has broadcast 20 distinct callsigns, including UAL1676, UAL1675, UAL1129, UAL8257, UAL763.