sensors Mode-S transponder

A0F55B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N16091 · CESSNA 150 · operated by TIMM MARK W

Hex
A0F55B
Octal
50172533
Decimal
10,548,571
Country
US
Tail
N16091
Type
C150
No current signal · last broadcast 2d ago
Flights observed
3
Distinct callsigns
1
Country
US
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S A0F55B.

Country allocation

The ICAO 24-bit address A0F55B 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
N16091 - 3 2026-04-21

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-21 N16091 - Apr 21, 23:15 UTCApr 21, 23:35 UTC20m
2026-04-19 N16091 - Apr 19, 15:00 UTCApr 19, 16:05 UTC1h 5m
2026-04-17 N16091 - Apr 17, 17:40 UTCApr 17, 18:30 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 N16091 page for operator, model, and routing details .

Mode-S A0F55B frequently asked

What is Mode-S code A0F55B?
A0F55B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N16091.
Where is Mode-S A0F55B registered?
Mode-S code A0F55B 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 A0F55B broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A0F55B, octal 50172533, decimal 10,548,571.
What flights does A0F55B operate?
Mode-S A0F55B has broadcast 1 distinct callsign, including N16091.