sensors Mode-S transponder

A123D7

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N1726T · CESSNA 172 Skyhawk · operated by FLIGHT OPERATIONS AIRCRAFT LLC

Hex
A123D7
Octal
50221727
Decimal
10,560,471
Country
US
Tail
N1726T
Type
C172
Broadcasting now · callsign CXK585 · 5,050 ft
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
16h ago

Current position

A123D7 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A123D7 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
CXK585 - 5 2026-04-14

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-14 CXK585 - Apr 14, 06:25 UTCApr 14, 07:05 UTC40m
2026-04-14 CXK585 PVU → PVU Apr 14, 05:15 UTCApr 14, 06:20 UTC1h 5m
2026-04-13 CXK585 OGD → OGD Apr 13, 20:15 UTCApr 13, 21:35 UTC1h 20m
2026-04-13 CXK585 OGD → OGD Apr 13, 17:25 UTCApr 13, 19:15 UTC1h 50m
2026-04-13 CXK585 OGD → OGD Apr 13, 12:20 UTCApr 13, 14:10 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 N1726T page for operator, model, and routing details .

Mode-S A123D7 frequently asked

What is Mode-S code A123D7?
A123D7 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N1726T.
Where is Mode-S A123D7 registered?
Mode-S code A123D7 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 A123D7 broadcasting right now?
Yes. Mode-S A123D7 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A123D7, octal 50221727, decimal 10,560,471.
What flights does A123D7 operate?
Mode-S A123D7 has broadcast 1 distinct callsign, including CXK585.