sensors Mode-S transponder

A6E6D4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N544AM · AEROSPATIALE AS-350 Ecureuil · operated by AIR METHODS LLC

Hex
A6E6D4
Octal
51563324
Decimal
10,938,068
Country
US
Tail
N544AM
Type
AS50
No current signal · last broadcast 8h ago
Flights observed
11
Distinct callsigns
1
Country
US
Last broadcast
8h ago

Last known position

Most recent position reported by Mode-S A6E6D4.

Country allocation

The ICAO 24-bit address A6E6D4 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
N544AM - 11 2026-04-18

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-04-18 N544AM - Apr 18, 10:15 UTCApr 18, 10:45 UTC30m
2026-04-18 N544AM - Apr 18, 09:25 UTCApr 18, 09:40 UTC15m
2026-04-17 N544AM - Apr 17, 19:25 UTCApr 17, 20:00 UTC35m
2026-04-17 N544AM - Apr 17, 17:25 UTCApr 17, 18:10 UTC45m
2026-04-16 N544AM - Apr 16, 18:05 UTCApr 16, 18:25 UTC20m
2026-04-16 N544AM - Apr 16, 16:40 UTCApr 16, 17:05 UTC25m
2026-04-15 N544AM - Apr 15, 07:40 UTCApr 15, 08:05 UTC25m
2026-04-15 N544AM - Apr 15, 07:01 UTCApr 15, 07:10 UTC10m
2026-04-15 N544AM - Apr 15, 06:25 UTCApr 15, 06:55 UTC30m
2026-04-14 N544AM - Apr 14, 19:00 UTCApr 14, 19:55 UTC55m
2026-04-14 N544AM - Apr 14, 17:55 UTCApr 14, 18:05 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 N544AM page for operator, model, and routing details .

Mode-S A6E6D4 frequently asked

What is Mode-S code A6E6D4?
A6E6D4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N544AM.
Where is Mode-S A6E6D4 registered?
Mode-S code A6E6D4 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 A6E6D4 broadcasting right now?
No active broadcast right now. Last signal was 8h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A6E6D4, octal 51563324, decimal 10,938,068.
What flights does A6E6D4 operate?
Mode-S A6E6D4 has broadcast 1 distinct callsign, including N544AM.