sensors Mode-S transponder

A4FE5A

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N42024 · CESSNA 172 Skyhawk · operated by FLY BY KNIGHT INC

Hex
A4FE5A
Octal
51177132
Decimal
10,813,018
Country
US
Tail
N42024
Type
C172
No current signal · last broadcast 6h ago
Flights observed
9
Distinct callsigns
1
Country
US
Last broadcast
6h ago

Last known position

Most recent position reported by Mode-S A4FE5A.

Country allocation

The ICAO 24-bit address A4FE5A 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
N42024 - 9 2026-04-18

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-04-18 N42024 - Apr 18, 13:30 UTCApr 18, 15:05 UTC1h 35m
2026-04-18 N42024 CRG → CRG Apr 18, 12:50 UTCApr 18, 13:00 UTC10m
2026-04-17 N42024 - Apr 17, 15:20 UTCApr 17, 16:00 UTC40m
2026-04-17 N42024 - Apr 17, 14:55 UTCApr 17, 15:15 UTC20m
2026-04-17 N42024 - Apr 17, 03:20 UTCApr 17, 04:15 UTC55m
2026-04-17 N42024 - Apr 17, 01:50 UTCApr 17, 03:15 UTC1h 25m
2026-04-14 N42024 - Apr 14, 15:05 UTCApr 14, 15:20 UTC15m
2026-04-13 N42024 - Apr 13, 20:35 UTCApr 13, 21:45 UTC1h 10m
2026-04-13 N42024 - Apr 13, 18:00 UTCApr 13, 19:20 UTC1h 20m

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 N42024 page for operator, model, and routing details .

Mode-S A4FE5A frequently asked

What is Mode-S code A4FE5A?
A4FE5A is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N42024.
Where is Mode-S A4FE5A registered?
Mode-S code A4FE5A 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 A4FE5A broadcasting right now?
No active broadcast right now. Last signal was 6h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4FE5A, octal 51177132, decimal 10,813,018.
What flights does A4FE5A operate?
Mode-S A4FE5A has broadcast 1 distinct callsign, including N42024.