sensors Mode-S transponder

A724D4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N56CS · PIAGGIO P-180 Avanti · operated by PENNY EQUIPMENT LLC

Hex
A724D4
Octal
51622324
Decimal
10,953,940
Country
US
Tail
N56CS
Type
P180
No current signal · last broadcast 15d ago
Flights observed
6
Distinct callsigns
1
Country
US
Last broadcast
15d ago

Last known position

Most recent position reported by Mode-S A724D4.

Country allocation

The ICAO 24-bit address A724D4 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
N56CS - 6 2026-05-18

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-05-18 N56CS VNY → OAK May 18, 17:55 UTCMay 18, 19:05 UTC1h 9m
2026-05-17 N56CS OAK → VNY May 17, 22:30 UTCMay 17, 23:20 UTC50m
2026-04-30 N56CS ABQ → OAK Apr 30, 22:05 UTCMay 1, 00:35 UTC2h 30m
2026-04-30 N56CS - Apr 30, 19:00 UTCApr 30, 21:15 UTC2h 15m
2026-04-30 N56CS - Apr 30, 17:35 UTCApr 30, 18:05 UTC30m
2026-04-22 N56CS - Apr 22, 19:20 UTCApr 22, 20:00 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 N56CS page for operator, model, and routing details .

Mode-S A724D4 frequently asked

What is Mode-S code A724D4?
A724D4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N56CS.
Where is Mode-S A724D4 registered?
Mode-S code A724D4 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 A724D4 broadcasting right now?
No active broadcast right now. Last signal was 15d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A724D4, octal 51622324, decimal 10,953,940.
What flights does A724D4 operate?
Mode-S A724D4 has broadcast 1 distinct callsign, including N56CS.