sensors Mode-S transponder

A3CBF4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N3438S · CESSNA 177 Cardinal · operated by HAWKEYE HELICOPTER LLC

Hex
A3CBF4
Octal
50745764
Decimal
10,734,580
Country
US
Tail
N3438S
Type
C177
No current signal · last broadcast 1d ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A3CBF4.

Country allocation

The ICAO 24-bit address A3CBF4 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 1 distinct

Callsign Airline Flights Last seen
N3438S - 5 2026-04-13

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-13 N3438S - Apr 13, 16:45 UTCApr 13, 18:20 UTC1h 35m
2026-04-13 N3438S - Apr 13, 13:05 UTCApr 13, 15:10 UTC2h 5m
2026-04-13 N3438S - Apr 13, 00:20 UTCApr 13, 00:45 UTC25m
2026-04-12 N3438S - Apr 12, 23:55 UTCApr 13, 00:45 UTC50m
2026-04-12 N3438S - Apr 12, 19:25 UTCApr 12, 20:15 UTC50m

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 N3438S page for operator, model, and routing details .

Mode-S A3CBF4 frequently asked

What is Mode-S code A3CBF4?
A3CBF4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N3438S.
Where is Mode-S A3CBF4 registered?
Mode-S code A3CBF4 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 A3CBF4 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A3CBF4, octal 50745764, decimal 10,734,580.
What flights does A3CBF4 operate?
Mode-S A3CBF4 has broadcast 1 distinct callsign, including N3438S.