sensors Mode-S transponder

A1C82C

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N2138W · CESSNA 172 Skyhawk · operated by CHRISTIANSEN AVIATION LLC

Hex
A1C82C
Octal
50344054
Decimal
10,602,540
Country
US
Tail
N2138W
Type
C172
Broadcasting now · callsign N2138W · 3,525 ft
Flights observed
6
Distinct callsigns
1
Country
US
Last broadcast
18h ago

Current position

A1C82C is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A1C82C 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
N2138W - 6 2026-04-14

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-14 N2138W - Apr 14, 05:15 UTCApr 14, 06:50 UTC1h 35m
2026-04-13 N2138W - Apr 13, 14:20 UTCApr 13, 15:45 UTC1h 25m
2026-04-13 N2138W - Apr 13, 02:20 UTCApr 13, 03:50 UTC1h 30m
2026-04-13 N2138W - Apr 13, 00:20 UTCApr 13, 01:30 UTC1h 10m
2026-04-12 N2138W - Apr 12, 23:55 UTCApr 13, 01:30 UTC1h 35m
2026-04-12 N2138W - Apr 12, 17:35 UTCApr 12, 19:25 UTC1h 50m

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 N2138W page for operator, model, and routing details .

Mode-S A1C82C frequently asked

What is Mode-S code A1C82C?
A1C82C is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N2138W.
Where is Mode-S A1C82C registered?
Mode-S code A1C82C 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 A1C82C broadcasting right now?
Yes. Mode-S A1C82C is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1C82C, octal 50344054, decimal 10,602,540.
What flights does A1C82C operate?
Mode-S A1C82C has broadcast 1 distinct callsign, including N2138W.