sensors Mode-S transponder

A7D7AB

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N604S · LEARJET 35 · operated by BUTLER NATIONAL INC

Hex
A7D7AB
Octal
51753653
Decimal
10,999,723
Country
US
Tail
N604S
Type
LJ35
No current signal · last broadcast 29d ago
Flights observed
11
Distinct callsigns
2
Country
US
Last broadcast
29d ago

Last known position

Most recent position reported by Mode-S A7D7AB.

Country allocation

The ICAO 24-bit address A7D7AB 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 2 distinct

Callsign Airline Flights Last seen
N604S - 6 2026-05-29
AVCON05 - 5 2026-05-26

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-05-29 N604S - May 29, 14:50 UTCMay 30, 14:25 UTC23h 35m
2026-05-29 N604S - May 29, 13:50 UTCMay 30, 08:00 UTC18h 10m
2026-05-29 N604S - May 29, 07:55 UTCMay 29, 12:25 UTC4h 30m
2026-05-28 N604S BGR → KEF May 28, 12:45 UTCMay 28, 19:50 UTC7h 5m
2026-05-27 N604S - May 27, 20:25 UTCMay 27, 22:30 UTC2h 5m
2026-05-27 N604S - May 27, 18:35 UTCMay 27, 19:35 UTC1h 0m
2026-05-26 AVCON05 - May 26, 19:30 UTCMay 26, 20:05 UTC35m
2026-05-14 AVCON05 - May 14, 19:55 UTCMay 14, 21:05 UTC1h 10m
2026-04-30 AVCON05 - Apr 30, 23:50 UTCMay 1, 00:15 UTC25m
2026-04-27 AVCON05 - Apr 27, 20:35 UTCApr 27, 21:15 UTC40m
2026-04-27 AVCON05 - Apr 27, 16:35 UTCApr 27, 19:05 UTC2h 30m

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 N604S page for operator, model, and routing details .

Mode-S A7D7AB frequently asked

What is Mode-S code A7D7AB?
A7D7AB is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N604S.
Where is Mode-S A7D7AB registered?
Mode-S code A7D7AB 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 A7D7AB broadcasting right now?
No active broadcast right now. Last signal was 29d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A7D7AB, octal 51753653, decimal 10,999,723.
What flights does A7D7AB operate?
Mode-S A7D7AB has broadcast 2 distinct callsigns, including N604S, AVCON05.