sensors Mode-S transponder

A5A725

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N4630N · CESSNA 402 Businessliner · operated by HYANNIS AIR SERVICE INC

Hex
A5A725
Octal
51323445
Decimal
10,856,229
Country
US
Tail
N4630N
Type
C402
Broadcasting now · callsign KAP413 · 2,700 ft
Flights observed
8
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Current position

A5A725 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A5A725 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
KAP42 Cape Air 8 2026-04-13

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-13 KAP42 AUG → BOS Apr 13, 18:20 UTCApr 13, 18:40 UTC20m
2026-04-13 KAP42 AUG → BOS Apr 13, 17:10 UTCApr 13, 17:45 UTC35m
2026-04-13 KAP42 AUG → BOS Apr 13, 16:15 UTCApr 13, 16:25 UTC10m
2026-04-13 KAP42 AUG → BOS Apr 13, 15:45 UTCApr 13, 16:15 UTC30m
2026-04-13 KAP42 AUG → BOS Apr 13, 12:45 UTCApr 13, 13:20 UTC35m
2026-04-13 KAP42 AUG → BOS Apr 13, 11:55 UTCApr 13, 12:00 UTC5m
2026-04-13 KAP42 AUG → BOS Apr 13, 11:15 UTCApr 13, 12:00 UTC45m
2026-04-13 KAP42 AUG → BOS Apr 13, 10:10 UTCApr 13, 10:25 UTC15m

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 N4630N page for operator, model, and routing details .

Mode-S A5A725 frequently asked

What is Mode-S code A5A725?
A5A725 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N4630N.
Where is Mode-S A5A725 registered?
Mode-S code A5A725 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 A5A725 broadcasting right now?
Yes. Mode-S A5A725 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A5A725, octal 51323445, decimal 10,856,229.
What flights does A5A725 operate?
Mode-S A5A725 has broadcast 1 distinct callsign, including KAP42.