sensors Mode-S transponder

A4CA73

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N408BA · CESSNA 408 SkyCourier · operated by NORTON BASIN SERVICES

Hex
A4CA73
Octal
51145163
Decimal
10,799,731
Country
US
Tail
N408BA
Type
C408
No current signal · last broadcast 13d ago
Flights observed
8
Distinct callsigns
4
Country
US
Last broadcast
13d ago

Last known position

Most recent position reported by Mode-S A4CA73.

Country allocation

The ICAO 24-bit address A4CA73 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 4 distinct

Callsign Airline Flights Last seen
BRG1088 Bering Air 5 2026-05-03
BRG1188 Bering Air 1 2026-04-24
BRG1080 Bering Air 1 2026-05-08
BRG1060 Bering Air 1 2026-05-08

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-05-08 BRG1060 DRG → OME May 8, 21:40 UTCMay 8, 22:55 UTC1h 15m
2026-05-08 BRG1080 OME → OTZ May 8, 19:30 UTCMay 8, 20:15 UTC45m
2026-05-03 BRG1088 SHH → OME May 3, 17:54 UTCMay 3, 18:05 UTC10m
2026-05-02 BRG1088 SHH → OME May 2, 21:55 UTCMay 2, 22:05 UTC10m
2026-04-26 BRG1088 SHH → OME Apr 26, 18:15 UTCApr 26, 18:30 UTC15m
2026-04-24 BRG1188 SHH → OME Apr 24, 23:35 UTCApr 24, 23:45 UTC10m
2026-04-24 BRG1088 SHH → OME Apr 24, 21:10 UTCApr 24, 21:25 UTC15m
2026-04-17 BRG1088 SHH → OME Apr 17, 21:05 UTCApr 17, 21:20 UTC15m

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 N408BA page for operator, model, and routing details .

Mode-S A4CA73 frequently asked

What is Mode-S code A4CA73?
A4CA73 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N408BA.
Where is Mode-S A4CA73 registered?
Mode-S code A4CA73 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 A4CA73 broadcasting right now?
No active broadcast right now. Last signal was 13d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4CA73, octal 51145163, decimal 10,799,731.
What flights does A4CA73 operate?
Mode-S A4CA73 has broadcast 4 distinct callsigns, including BRG1088, BRG1188, BRG1080, BRG1060.