sensors Mode-S transponder

0ACB2D

ICAO 24-bit transponder address · allocated to Costa Rica

Currently assigned to HK-5434 · BOEING 737-400

Hex
0ACB2D
Octal
02545455
Decimal
707,373
Country
CR
Tail
HK-5434
Type
B734
No current signal · last broadcast 20h ago
Flights observed
6
Distinct callsigns
6
Country
CR
Last broadcast
20h ago

Last known position

Most recent position reported by Mode-S 0ACB2D.

Country allocation

The ICAO 24-bit address 0ACB2D 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 6 distinct

Callsign Airline Flights Last seen
KRE472 - 1 2026-04-13
KRE373 - 1 2026-04-13
KRE372 - 1 2026-04-13
KRE172 - 1 2026-04-12
KRE170 - 1 2026-04-14
KRE140 - 1 2026-04-14

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-14 KRE170 - Apr 14, 10:10 UTCApr 14, 10:30 UTC20m
2026-04-14 KRE140 - Apr 14, 05:15 UTCApr 14, 05:25 UTC10m
2026-04-13 KRE472 - Apr 13, 21:25 UTCApr 13, 21:40 UTC15m
2026-04-13 KRE373 - Apr 13, 19:15 UTCApr 13, 19:35 UTC20m
2026-04-13 KRE372 - Apr 13, 15:35 UTCApr 13, 15:40 UTC5m
2026-04-12 KRE172 - Apr 12, 19:50 UTCApr 12, 20:05 UTC15m

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-5434 page for operator, model, and routing details .

Mode-S 0ACB2D frequently asked

What is Mode-S code 0ACB2D?
0ACB2D is an ICAO 24-bit transponder address. Allocated to Costa Rica. Assigned to HK-5434.
Where is Mode-S 0ACB2D registered?
Mode-S code 0ACB2D 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 0ACB2D broadcasting right now?
No active broadcast right now. Last signal was 20h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 0ACB2D, octal 02545455, decimal 707,373.
What flights does 0ACB2D operate?
Mode-S 0ACB2D has broadcast 6 distinct callsigns, including KRE472, KRE373, KRE372, KRE172, KRE170.