sensors Mode-S transponder

0ACA7E

ICAO 24-bit transponder address · allocated to Costa Rica

Currently assigned to HK-5404 · ATR-72-600

Hex
0ACA7E
Octal
02545176
Decimal
707,198
Country
CR
Tail
HK-5404
Type
AT76
Broadcasting now · callsign EFY9131 · 12,500 ft
Flights observed
8
Distinct callsigns
8
Country
CR
Last broadcast
1d ago

Current position

0ACA7E is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 0ACA7E 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 8 distinct

Callsign Airline Flights Last seen
EFY9017 - 1 2026-04-13
EFY9016 - 1 2026-04-13
EFY8995 - 1 2026-04-12
EFY8942 - 1 2026-04-13
EFY7835 - 1 2026-04-13
EFY7834 - 1 2026-04-13
EFY6979 EasyFly 1 2026-04-13
EFY6978 - 1 2026-04-13

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-13 EFY8942 - Apr 13, 22:30 UTCApr 13, 22:45 UTC15m
2026-04-13 EFY9017 - Apr 13, 20:55 UTCApr 13, 21:20 UTC25m
2026-04-13 EFY9016 - Apr 13, 17:30 UTCApr 13, 17:45 UTC15m
2026-04-13 EFY7835 - Apr 13, 16:20 UTCApr 13, 16:40 UTC20m
2026-04-13 EFY7834 - Apr 13, 14:05 UTCApr 13, 14:25 UTC20m
2026-04-13 EFY6979 EJA → BOG Apr 13, 12:30 UTCApr 13, 12:50 UTC20m
2026-04-13 EFY6978 - Apr 13, 10:45 UTCApr 13, 11:05 UTC20m
2026-04-12 EFY8995 - Apr 12, 19:40 UTCApr 12, 20:00 UTC20m

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-5404 page for operator, model, and routing details .

Mode-S 0ACA7E frequently asked

What is Mode-S code 0ACA7E?
0ACA7E is an ICAO 24-bit transponder address. Allocated to Costa Rica. Assigned to HK-5404.
Where is Mode-S 0ACA7E registered?
Mode-S code 0ACA7E 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 0ACA7E broadcasting right now?
Yes. Mode-S 0ACA7E is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 0ACA7E, octal 02545176, decimal 707,198.
What flights does 0ACA7E operate?
Mode-S 0ACA7E has broadcast 8 distinct callsigns, including EFY9017, EFY9016, EFY8995, EFY8942, EFY7835.