sensors Mode-S transponder

A8EC53

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N674TX · AEROSPATIALE AS-350 Ecureuil · operated by TEXAS DEPARTMENT OF PUBLIC SAFETY

Hex
A8EC53
Octal
52166123
Decimal
11,070,547
Country
US
Tail
N674TX
Type
AS50
No current signal · last broadcast 14h ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
14h ago

Last known position

Most recent position reported by Mode-S A8EC53.

Country allocation

The ICAO 24-bit address A8EC53 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
N674TX - 5 2026-04-14

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-14 N674TX - Apr 14, 07:25 UTCApr 14, 08:15 UTC50m
2026-04-14 N674TX - Apr 14, 05:15 UTCApr 14, 06:55 UTC1h 40m
2026-04-13 N674TX - Apr 13, 05:10 UTCApr 13, 05:40 UTC30m
2026-04-13 N674TX - Apr 13, 03:55 UTCApr 13, 04:15 UTC20m
2026-04-13 N674TX - Apr 13, 02:30 UTCApr 13, 03:10 UTC40m

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 N674TX page for operator, model, and routing details .

Mode-S A8EC53 frequently asked

What is Mode-S code A8EC53?
A8EC53 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N674TX.
Where is Mode-S A8EC53 registered?
Mode-S code A8EC53 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 A8EC53 broadcasting right now?
No active broadcast right now. Last signal was 14h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A8EC53, octal 52166123, decimal 11,070,547.
What flights does A8EC53 operate?
Mode-S A8EC53 has broadcast 1 distinct callsign, including N674TX.