Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

0AC333

ICAO 24-bit transponder address · allocated to Costa Rica

Currently assigned to HK-5139 · BOEING 737-400

Hex
0AC333
Octal
02541463
Decimal
705,331
Country
CR
Tail
HK-5139
Type
B734
No current signal · last broadcast 1h ago
Flights observed
118
Distinct callsigns
17
Country
CR
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S 0AC333.

Country allocation

The ICAO 24-bit address 0AC333 falls within the block assigned to Costa Rica (CR) by ICAO Annex 10, Volume III. Every aircraft registered in Costa Rica 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 17 distinct

Callsign Airline Flights Last seen
HK5139 - 58 2026-06-02
ACL1171 Itali Airlines 14 2026-05-28
ACL1172 - 13 2026-05-28
ACL5139 - 7 2026-05-31
ACL864 - 4 2026-05-06
ACL865 - 3 2026-06-02
ACL1173 Itali Airlines 3 2026-05-25
ACL1156 Itali Airlines 3 2026-05-29
ACL1155 Itali Airlines 3 2026-05-22
ACL1165 Itali Airlines 2 2026-05-27
ACL1154 - 2 2026-05-20
ACL1164 - 1 2026-05-20
ACL1163 Itali Airlines 1 2026-05-20
ACL1162 - 1 2026-05-21
ACL1161 - 1 2026-05-21
ACL1159 Itali Airlines 1 2026-05-27
ACL1153 Itali Airlines 1 2026-05-20

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-06-02 HK5139 - Jun 2, 17:55 UTCJun 2, 18:05 UTC10m
2026-06-02 ACL865 - Jun 2, 14:10 UTCJun 2, 14:25 UTC15m
2026-06-01 ACL865 - Jun 1, 18:15 UTCJun 1, 19:30 UTC1h 15m
2026-05-31 ACL5139 - May 31, 00:05 UTCMay 31, 11:30 UTC11h 25m
2026-05-30 HK5139 - May 30, 15:05 UTCMay 30, 17:20 UTC2h 15m
2026-05-29 HK5139 - May 29, 22:10 UTCMay 30, 00:40 UTC2h 30m
2026-05-29 HK5139 - May 29, 18:05 UTCMay 29, 20:20 UTC2h 15m
2026-05-29 ACL1156 BOG → SJO May 29, 06:25 UTCMay 29, 06:45 UTC20m
2026-05-29 HK5139 - May 29, 00:10 UTCMay 29, 00:30 UTC20m
2026-05-28 HK5139 - May 28, 17:55 UTCMay 28, 20:10 UTC2h 15m
2026-05-28 ACL1171 CUR → BOG May 28, 13:40 UTCMay 28, 15:00 UTC1h 20m
2026-05-28 ACL1172 - May 28, 07:35 UTCMay 28, 11:00 UTC3h 25m
2026-05-28 HK5139 - May 28, 00:15 UTCMay 28, 00:35 UTC20m
2026-05-27 HK5139 - May 27, 20:20 UTCMay 27, 20:30 UTC10m
2026-05-27 HK5139 - May 27, 18:10 UTCMay 27, 18:25 UTC15m
2026-05-27 ACL1165 MIA → BOG May 27, 15:05 UTCMay 27, 15:20 UTC15m
2026-05-27 ACL1165 MIA → BOG May 27, 12:15 UTCMay 27, 12:40 UTC25m
2026-05-27 ACL1159 SJO → MIA May 27, 04:55 UTCMay 27, 10:20 UTC5h 25m
2026-05-26 HK5139 - May 26, 18:10 UTCMay 26, 20:24 UTC2h 15m
2026-05-25 ACL1171 CUR → BOG May 25, 13:10 UTCMay 25, 14:30 UTC1h 20m
2026-05-25 ACL1172 - May 25, 11:10 UTCMay 25, 11:20 UTC10m
2026-05-25 ACL1172 - May 25, 06:50 UTCMay 25, 10:25 UTC3h 35m
2026-05-25 ACL1173 CCS → BOG May 25, 04:30 UTCMay 25, 04:50 UTC20m
2026-05-24 HK5139 - May 24, 20:05 UTCMay 24, 20:20 UTC15m
2026-05-24 ACL1171 CUR → BOG May 24, 14:50 UTCMay 24, 15:05 UTC15m
2026-05-24 ACL1171 CUR → BOG May 24, 13:50 UTCMay 24, 14:00 UTC10m
2026-05-24 ACL1172 - May 24, 06:15 UTCMay 24, 10:25 UTC4h 10m
2026-05-23 ACL5139 - May 23, 22:55 UTCMay 24, 01:00 UTC2h 5m
2026-05-23 HK5139 - May 23, 15:15 UTCMay 23, 16:00 UTC45m
2026-05-23 HK5139 - May 23, 13:50 UTCMay 23, 14:00 UTC10m
2026-05-23 HK5139 - May 23, 02:10 UTCMay 23, 02:30 UTC20m
2026-05-23 HK5139 - May 23, 00:05 UTCMay 23, 00:50 UTC45m
2026-05-22 HK5139 - May 22, 20:10 UTCMay 22, 22:20 UTC2h 10m
2026-05-22 ACL1171 CUR → BOG May 22, 14:00 UTCMay 22, 17:20 UTC3h 20m
2026-05-22 ACL1155 SJO → BOG May 22, 11:40 UTCMay 22, 11:50 UTC10m
2026-05-22 ACL1156 BOG → SJO May 22, 05:40 UTCMay 22, 05:55 UTC15m
2026-05-21 ACL1161 - May 21, 19:40 UTCMay 21, 21:15 UTC1h 35m
2026-05-21 ACL1162 - May 21, 16:50 UTCMay 21, 18:20 UTC1h 30m
2026-05-21 ACL1171 CUR → BOG May 21, 13:55 UTCMay 21, 14:10 UTC15m
2026-05-21 ACL1172 - May 21, 06:25 UTCMay 21, 13:05 UTC6h 40m
2026-05-20 ACL1163 CCS → BOG May 20, 22:55 UTCMay 20, 23:05 UTC10m
2026-05-20 ACL1164 - May 20, 19:05 UTCMay 20, 19:20 UTC15m
2026-05-20 ACL1153 CLO → BOG May 20, 13:55 UTCMay 20, 14:15 UTC20m
2026-05-20 ACL1154 - May 20, 09:20 UTCMay 20, 09:35 UTC15m
2026-05-19 HK5139 - May 19, 23:25 UTCMay 20, 01:50 UTC2h 25m
2026-05-19 HK5139 - May 19, 19:05 UTCMay 19, 21:15 UTC2h 10m
2026-05-19 ACL1171 CUR → BOG May 19, 16:00 UTCMay 19, 16:15 UTC15m
2026-05-19 ACL1171 CUR → BOG May 19, 14:50 UTCMay 19, 15:05 UTC15m
2026-05-19 ACL1172 - May 19, 09:00 UTCMay 19, 12:20 UTC3h 20m
2026-05-18 ACL1173 CCS → BOG May 18, 05:45 UTCMay 18, 05:55 UTC10m

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 HK-5139 page for operator, model, and routing details .

Mode-S 0AC333 frequently asked

What is Mode-S code 0AC333?
0AC333 is an ICAO 24-bit transponder address. Allocated to Costa Rica. Assigned to HK-5139.
Where is Mode-S 0AC333 registered?
Mode-S code 0AC333 is allocated to Costa Rica (CR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 0AC333 broadcasting right now?
No active broadcast right now. Last signal was 1h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 0AC333, octal 02541463, decimal 705,331.
What flights does 0AC333 operate?
Mode-S 0AC333 has broadcast 17 distinct callsigns, including HK5139, ACL1171, ACL1172, ACL5139, ACL864.