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sensors Mode-S transponder

0AC9DC

ICAO 24-bit transponder address · allocated to Costa Rica

Currently assigned to HK-5357 · BOEING 737-400

Hex
0AC9DC
Octal
02544734
Decimal
707,036
Country
CR
Tail
HK-5357
Type
B734
Broadcasting now · callsign ACL1161 · 9,525 ft
Flights observed
168
Distinct callsigns
20
Country
CR
Last broadcast
1h ago

Current position

0AC9DC is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 0AC9DC 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 20 distinct

Callsign Airline Flights Last seen
ACL1162 - 33 2026-07-18
ACL1161 - 28 2026-07-16
HK5357 - 23 2026-07-14
ACL1165 Itali Airlines 11 2026-06-10
ACL865 - 10 2026-07-10
ACL864 - 8 2026-07-10
ACL1173 - 6 2026-07-13
ACL1171 - 6 2026-07-02
ACL1153 Itali Airlines 6 2026-05-25
ACL1166 Itali Airlines 5 2026-05-24
ACL1172 - 4 2026-05-23
ACL1168 - 4 2026-07-17
ACL1154 Itali Airlines 4 2026-06-17
ACL1167 - 3 2026-07-17
ACL1155 - 3 2026-07-18
ACL5139 - 2 2026-05-02
ACL1170 - 2 2026-06-19
ACL1163 Itali Airlines 2 2026-05-24
ACL1159 Itali Airlines 2 2026-06-10
ACL1156 - 2 2026-06-19

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-18 ACL1162 - Jul 18, 21:10 UTCJul 18, 21:40 UTC30m
2026-07-18 ACL1162 - Jul 18, 20:05 UTCJul 18, 20:20 UTC15m
2026-07-18 ACL1155 - Jul 18, 09:40 UTCJul 18, 13:10 UTC3h 30m
2026-07-17 ACL1167 - Jul 17, 16:55 UTCJul 17, 17:30 UTC35m
2026-07-17 ACL1168 - Jul 17, 15:15 UTCJul 17, 15:29 UTC15m
2026-07-16 ACL1161 - Jul 16, 00:55 UTCJul 16, 01:30 UTC35m
2026-07-15 ACL1162 - Jul 15, 23:05 UTCJul 15, 23:30 UTC25m
2026-07-15 ACL1162 - Jul 15, 22:05 UTCJul 15, 22:15 UTC10m
2026-07-14 HK5357 - Jul 14, 23:20 UTCJul 14, 23:35 UTC15m
2026-07-14 HK5357 - Jul 14, 17:05 UTCJul 14, 17:20 UTC15m
2026-07-13 ACL1173 - Jul 13, 04:30 UTCJul 13, 04:45 UTC15m
2026-07-12 HK5357 - Jul 12, 18:10 UTCJul 12, 19:20 UTC1h 10m
2026-07-12 HK5357 - Jul 12, 13:45 UTCJul 12, 16:05 UTC2h 20m
2026-07-11 ACL1161 LET → BOG Jul 11, 23:40 UTCJul 12, 01:25 UTC1h 45m
2026-07-11 ACL1162 BOG → LET Jul 11, 19:55 UTCJul 11, 21:25 UTC1h 30m
2026-07-11 ACL1155 SJO → BOG Jul 11, 09:25 UTCJul 11, 13:05 UTC3h 40m
2026-07-10 ACL865 - Jul 10, 13:15 UTCJul 10, 14:35 UTC1h 20m
2026-07-10 ACL864 - Jul 10, 10:20 UTCJul 10, 10:35 UTC15m
2026-07-10 ACL1161 - Jul 10, 01:00 UTCJul 10, 02:40 UTC1h 40m
2026-07-09 ACL1162 - Jul 9, 22:45 UTCJul 9, 23:10 UTC25m
2026-07-09 ACL1162 - Jul 9, 21:40 UTCJul 9, 21:50 UTC10m
2026-07-08 ACL865 - Jul 8, 13:25 UTCJul 8, 13:35 UTC10m
2026-07-08 ACL1161 - Jul 8, 01:55 UTCJul 8, 02:25 UTC30m
2026-07-07 ACL1162 - Jul 7, 20:55 UTCJul 7, 22:30 UTC1h 35m
2026-07-06 ACL1173 - Jul 6, 02:10 UTCJul 6, 02:30 UTC20m
2026-07-04 ACL1161 - Jul 4, 23:45 UTCJul 5, 16:40 UTC16h 55m
2026-07-04 ACL1162 - Jul 4, 21:25 UTCJul 4, 21:50 UTC25m
2026-07-03 ACL865 - Jul 3, 13:40 UTCJul 3, 19:35 UTC5h 55m
2026-07-02 ACL1171 - Jul 2, 13:25 UTCJul 2, 20:00 UTC6h 35m
2026-07-01 ACL1161 - Jul 1, 23:40 UTCJul 2, 00:15 UTC35m
2026-07-01 ACL1162 - Jul 1, 21:10 UTCJul 1, 21:35 UTC25m
2026-06-30 ACL865 - Jun 30, 13:10 UTCJun 30, 13:20 UTC10m
2026-06-27 ACL1161 - Jun 27, 22:20 UTCJun 27, 22:45 UTC25m
2026-06-27 ACL1162 - Jun 27, 20:44 UTCJun 27, 21:04 UTC20m
2026-06-25 ACL1161 - Jun 25, 23:09 UTCJun 25, 23:44 UTC35m
2026-06-25 ACL1162 - Jun 25, 21:40 UTCJun 25, 22:10 UTC30m
2026-06-23 ACL1161 - Jun 23, 23:29 UTCJun 23, 23:59 UTC30m
2026-06-23 ACL1162 - Jun 23, 21:54 UTCJun 23, 22:19 UTC25m
2026-06-21 HK5357 - Jun 21, 13:20 UTCJun 21, 23:24 UTC10h 5m
2026-06-20 ACL1161 - Jun 20, 23:10 UTCJun 20, 23:39 UTC30m
2026-06-20 ACL1162 - Jun 20, 21:00 UTCJun 20, 21:30 UTC30m
2026-06-19 ACL1170 BOG → BOG Jun 19, 13:50 UTCJun 19, 16:59 UTC3h 10m
2026-06-19 ACL1156 BOG → BOG Jun 19, 05:59 UTCJun 19, 12:14 UTC6h 15m
2026-06-19 HK5357 - Jun 19, 03:15 UTCJun 19, 03:29 UTC15m
2026-06-18 HK5357 - Jun 18, 13:30 UTCJun 18, 13:45 UTC15m
2026-06-18 ACL1161 - Jun 18, 02:20 UTCJun 18, 03:55 UTC1h 35m
2026-06-18 ACL1162 - Jun 18, 00:35 UTCJun 18, 01:00 UTC25m
2026-06-17 ACL1154 BOG → PTY Jun 17, 16:50 UTCJun 17, 17:05 UTC15m
2026-06-17 ACL865 - Jun 17, 13:10 UTCJun 17, 14:30 UTC1h 20m
2026-06-17 ACL864 - Jun 17, 10:15 UTCJun 17, 10:25 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-5357 page for operator, model, and routing details .

Mode-S 0AC9DC frequently asked

What is Mode-S code 0AC9DC?
0AC9DC is an ICAO 24-bit transponder address. Allocated to Costa Rica. Assigned to HK-5357.
Where is Mode-S 0AC9DC registered?
Mode-S code 0AC9DC 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 0AC9DC broadcasting right now?
Yes. Mode-S 0AC9DC is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 0AC9DC, octal 02544734, decimal 707,036.
What flights does 0AC9DC operate?
Mode-S 0AC9DC has broadcast 20 distinct callsigns, including ACL1162, ACL1161, HK5357, ACL1165, ACL865.