sensors Mode-S transponder

A17A1A

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N1945M · CESSNA 182 Skylane · operated by OCHS ROLAND P

Hex
A17A1A
Octal
50275032
Decimal
10,582,554
Country
US
Tail
N1945M
Type
C182
No current signal · last broadcast Jul 25, 19:40 UTC
Flights observed
9
Distinct callsigns
1
Country
US
Last broadcast
Jul 25, 19:40 UTC

Last known position

Most recent position reported by Mode-S A17A1A.

Country allocation

The ICAO 24-bit address A17A1A 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
N1945M - 9 2026-07-25

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-07-25 N1945M - Jul 25, 19:20 UTCJul 25, 19:40 UTC20m
2026-07-25 N1945M - Jul 25, 16:35 UTCJul 25, 17:05 UTC30m
2026-07-24 N1945M - Jul 24, 11:15 UTCJul 24, 13:15 UTC2h 0m
2026-07-17 N1945M - Jul 17, 14:00 UTCJul 17, 14:35 UTC35m
2026-07-16 N1945M - Jul 16, 16:25 UTCJul 16, 17:35 UTC1h 10m
2026-05-25 N1945M - May 25, 15:30 UTCMay 25, 15:40 UTC10m
2026-05-25 N1945M - May 25, 13:10 UTCMay 25, 13:25 UTC15m
2026-05-02 N1945M - May 2, 14:15 UTCMay 2, 14:25 UTC10m
2026-05-02 N1945M - May 2, 13:10 UTCMay 2, 13:20 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 N1945M page for operator, model, and routing details .

Mode-S A17A1A frequently asked

What is Mode-S code A17A1A?
A17A1A is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N1945M.
Where is Mode-S A17A1A registered?
Mode-S code A17A1A 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 A17A1A broadcasting right now?
No active broadcast right now. Last signal was Jul 25, 19:40 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A17A1A, octal 50275032, decimal 10,582,554.
What flights does A17A1A operate?
Mode-S A17A1A has broadcast 1 distinct callsign, including N1945M.