sensors Mode-S transponder

A740A3

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N56679 · PIPER PA-28-140/150/160/180 · operated by WORTHINGTON BRIAN M

Hex
A740A3
Octal
51640243
Decimal
10,961,059
Country
US
Tail
N56679
Type
P28A
No current signal · last broadcast 3d ago
Flights observed
4
Distinct callsigns
1
Country
US
Last broadcast
3d ago

Last known position

Most recent position reported by Mode-S A740A3.

Country allocation

The ICAO 24-bit address A740A3 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
N56679 - 4 2026-04-20

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-20 N56679 OCE → FRG Apr 20, 23:55 UTCApr 21, 01:50 UTC1h 55m
2026-04-20 N56679 - Apr 20, 18:15 UTCApr 20, 19:55 UTC1h 40m
2026-04-14 N56679 - Apr 14, 23:25 UTCApr 15, 00:35 UTC1h 10m
2026-04-14 N56679 - Apr 14, 19:05 UTCApr 14, 20:15 UTC1h 10m

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 N56679 page for operator, model, and routing details .

Mode-S A740A3 frequently asked

What is Mode-S code A740A3?
A740A3 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N56679.
Where is Mode-S A740A3 registered?
Mode-S code A740A3 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 A740A3 broadcasting right now?
No active broadcast right now. Last signal was 3d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A740A3, octal 51640243, decimal 10,961,059.
What flights does A740A3 operate?
Mode-S A740A3 has broadcast 1 distinct callsign, including N56679.