sensors Mode-S transponder

A4D6BD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N41019 · CESSNA 421 Executive Commuter · operated by SJS FLIGHTS LP

Hex
A4D6BD
Octal
51153275
Decimal
10,802,877
Country
US
Tail
N41019
Type
C421
No current signal · last broadcast 12h ago
Flights observed
14
Distinct callsigns
1
Country
US
Last broadcast
12h ago

Last known position

Most recent position reported by Mode-S A4D6BD.

Country allocation

The ICAO 24-bit address A4D6BD 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
N41019 - 14 2026-05-29

Recent flights last 14

DateFlightRouteTakeoffLandingDuration
2026-05-29 N41019 - May 29, 14:55 UTCMay 29, 17:35 UTC2h 40m
2026-05-29 N41019 - May 29, 11:10 UTCMay 29, 13:55 UTC2h 45m
2026-05-20 N41019 - May 20, 19:30 UTCMay 20, 22:10 UTC2h 40m
2026-05-20 N41019 - May 20, 15:40 UTCMay 20, 18:20 UTC2h 40m
2026-05-17 N41019 - May 17, 18:05 UTCMay 17, 20:40 UTC2h 35m
2026-05-17 N41019 - May 17, 14:01 UTCMay 17, 16:45 UTC2h 45m
2026-05-15 N41019 - May 15, 22:00 UTCMay 16, 00:40 UTC2h 40m
2026-05-15 N41019 - May 15, 19:50 UTCMay 15, 20:35 UTC45m
2026-05-15 N41019 - May 15, 17:00 UTCMay 15, 19:05 UTC2h 5m
2026-05-05 N41019 - May 5, 18:05 UTCMay 5, 19:10 UTC1h 5m
2026-05-05 N41019 - May 5, 12:50 UTCMay 5, 14:00 UTC1h 10m
2026-04-25 N41019 - Apr 25, 12:50 UTCApr 25, 13:35 UTC45m
2026-04-25 N41019 - Apr 25, 10:30 UTCApr 25, 12:00 UTC1h 30m
2026-04-23 N41019 - Apr 23, 19:15 UTCApr 23, 19:30 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 N41019 page for operator, model, and routing details .

Mode-S A4D6BD frequently asked

What is Mode-S code A4D6BD?
A4D6BD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N41019.
Where is Mode-S A4D6BD registered?
Mode-S code A4D6BD 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 A4D6BD broadcasting right now?
No active broadcast right now. Last signal was 12h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4D6BD, octal 51153275, decimal 10,802,877.
What flights does A4D6BD operate?
Mode-S A4D6BD has broadcast 1 distinct callsign, including N41019.