sensors Mode-S transponder

A19F1C

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N203W · operated by MICHIGAN AVIATION LLC

Hex
A19F1C
Octal
50317434
Decimal
10,592,028
Country
US
Tail
N203W
No current signal · last broadcast 2h ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S A19F1C.

Country allocation

The ICAO 24-bit address A19F1C 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
N203W - 5 2026-05-25

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-05-25 N203W - May 25, 18:30 UTCMay 25, 18:50 UTC20m
2026-05-17 N203W - May 17, 16:01 UTCMay 17, 17:01 UTC1h 0m
2026-05-16 N203W - May 16, 20:00 UTCMay 16, 20:40 UTC40m
2026-05-10 N203W - May 10, 14:45 UTCMay 10, 15:39 UTC55m
2026-05-09 N203W - May 9, 19:49 UTCMay 9, 20:10 UTC20m

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 N203W page for operator, model, and routing details .

Mode-S A19F1C frequently asked

What is Mode-S code A19F1C?
A19F1C is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N203W.
Where is Mode-S A19F1C registered?
Mode-S code A19F1C 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 A19F1C broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A19F1C, octal 50317434, decimal 10,592,028.
What flights does A19F1C operate?
Mode-S A19F1C has broadcast 1 distinct callsign, including N203W.