sensors Mode-S transponder

A4BF0B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N40485 · operated by AERO SERVICES LC

Hex
A4BF0B
Octal
51137413
Decimal
10,796,811
Country
US
Tail
N40485
No current signal · last broadcast Jul 25, 14:25 UTC
Flights observed
12
Distinct callsigns
1
Country
US
Last broadcast
Jul 25, 14:25 UTC

Last known position

Most recent position reported by Mode-S A4BF0B.

Country allocation

The ICAO 24-bit address A4BF0B 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
N40485 - 12 2026-07-25

Recent flights last 12

DateFlightRouteTakeoffLandingDuration
2026-07-25 N40485 - Jul 25, 13:50 UTCJul 25, 14:25 UTC35m
2026-07-24 N40485 BTF → BTF Jul 24, 14:00 UTCJul 24, 14:25 UTC25m
2026-07-20 N40485 - Jul 20, 13:35 UTCJul 20, 14:05 UTC30m
2026-07-18 N40485 - Jul 18, 15:35 UTCJul 18, 16:10 UTC35m
2026-07-18 N40485 - Jul 18, 14:00 UTCJul 18, 14:10 UTC10m
2026-07-01 N40485 - Jul 1, 13:20 UTCJul 1, 13:55 UTC35m
2026-06-29 N40485 - Jun 29, 13:24 UTCJun 29, 13:44 UTC20m
2026-06-25 N40485 BTF → BTF Jun 25, 12:50 UTCJun 25, 13:00 UTC10m
2026-06-23 N40485 - Jun 23, 13:19 UTCJun 23, 13:45 UTC25m
2026-06-15 N40485 - Jun 15, 02:44 UTCJun 15, 03:10 UTC25m
2026-06-13 N40485 - Jun 13, 14:25 UTCJun 13, 15:30 UTC1h 5m
2026-06-12 N40485 - Jun 12, 12:55 UTCJun 12, 13:05 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 N40485 page for operator, model, and routing details .

Mode-S A4BF0B frequently asked

What is Mode-S code A4BF0B?
A4BF0B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N40485.
Where is Mode-S A4BF0B registered?
Mode-S code A4BF0B 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 A4BF0B broadcasting right now?
No active broadcast right now. Last signal was Jul 25, 14:25 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4BF0B, octal 51137413, decimal 10,796,811.
What flights does A4BF0B operate?
Mode-S A4BF0B has broadcast 1 distinct callsign, including N40485.