Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A54D23

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N4401L · CESSNA 172 Skyhawk · operated by WARBELOWS AIR VENTURES

Hex
A54D23
Octal
51246443
Decimal
10,833,187
Country
US
Tail
N4401L
Type
C172
No current signal · last broadcast 9h ago
Flights observed
322
Distinct callsigns
1
Country
US
Last broadcast
9h ago

Last known position

Most recent position reported by Mode-S A54D23.

Country allocation

The ICAO 24-bit address A54D23 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
N4401L - 322 2026-07-18

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-18 N4401L - Jul 18, 07:40 UTCJul 18, 08:20 UTC40m
2026-07-18 N4401L - Jul 18, 06:00 UTCJul 18, 06:30 UTC30m
2026-07-18 N4401L - Jul 18, 04:40 UTCJul 18, 05:15 UTC35m
2026-07-18 N4401L - Jul 18, 02:55 UTCJul 18, 03:20 UTC25m
2026-07-18 N4401L - Jul 18, 01:15 UTCJul 18, 01:54 UTC40m
2026-07-18 N4401L - Jul 18, 00:25 UTCJul 18, 01:05 UTC40m
2026-07-17 N4401L FAI → FAI Jul 17, 22:20 UTCJul 17, 23:50 UTC1h 30m
2026-07-17 N4401L MLY → FAI Jul 17, 19:45 UTCJul 17, 20:25 UTC40m
2026-07-17 N4401L - Jul 17, 18:05 UTCJul 17, 18:55 UTC50m
2026-07-17 N4401L - Jul 17, 04:39 UTCJul 17, 05:20 UTC40m
2026-07-17 N4401L - Jul 17, 02:34 UTCJul 17, 03:20 UTC45m
2026-07-17 N4401L FAI → FAI Jul 17, 01:00 UTCJul 17, 02:05 UTC1h 5m
2026-07-17 N4401L FAI → FAI Jul 17, 00:10 UTCJul 17, 00:14 UTC5m
2026-07-16 N4401L FAI → FAI Jul 16, 23:29 UTCJul 17, 00:04 UTC35m
2026-07-16 N4401L FAI → FAI Jul 16, 21:19 UTCJul 16, 21:50 UTC30m
2026-07-16 N4401L FAI → FAI Jul 16, 21:10 UTCJul 16, 21:15 UTC5m
2026-07-14 N4401L FAI → FAI Jul 14, 19:05 UTCJul 14, 19:55 UTC50m
2026-07-13 N4401L FAI → FAI Jul 13, 18:45 UTCJul 13, 19:40 UTC55m
2026-07-12 N4401L MLY → FAI Jul 12, 22:45 UTCJul 12, 23:30 UTC45m
2026-07-12 N4401L FAI → MLY Jul 12, 20:55 UTCJul 12, 21:40 UTC45m
2026-07-12 N4401L FAI → FAI Jul 12, 18:30 UTCJul 12, 20:01 UTC1h 30m
2026-07-11 N4401L MLY → FAI Jul 11, 23:20 UTCJul 12, 00:20 UTC1h 0m
2026-07-11 N4401L FAI → MLY Jul 11, 20:55 UTCJul 11, 21:40 UTC45m
2026-07-11 N4401L - Jul 11, 17:10 UTCJul 11, 18:25 UTC1h 15m
2026-07-11 N4401L - Jul 11, 15:15 UTCJul 11, 16:20 UTC1h 5m
2026-07-11 N4401L - Jul 11, 05:10 UTCJul 11, 07:10 UTC2h 0m
2026-07-11 N4401L - Jul 11, 04:10 UTCJul 11, 04:40 UTC30m
2026-07-11 N4401L - Jul 11, 00:20 UTCJul 11, 00:45 UTC25m
2026-07-10 N4401L - Jul 10, 21:15 UTCJul 10, 22:05 UTC50m
2026-07-10 N4401L FAI → ENN Jul 10, 20:45 UTCJul 10, 21:05 UTC20m
2026-07-09 N4401L FAI → FAI Jul 9, 00:35 UTCJul 9, 01:50 UTC1h 15m
2026-07-08 N4401L - Jul 8, 22:15 UTCJul 8, 22:50 UTC35m
2026-07-08 N4401L - Jul 8, 18:25 UTCJul 8, 18:55 UTC30m
2026-07-08 N4401L - Jul 8, 06:30 UTCJul 8, 06:50 UTC20m
2026-07-08 N4401L - Jul 8, 02:40 UTCJul 8, 03:05 UTC25m
2026-07-07 N4401L MLY → FAI Jul 7, 19:50 UTCJul 7, 20:40 UTC50m
2026-07-07 N4401L FAI → MLY Jul 7, 18:10 UTCJul 7, 18:50 UTC40m
2026-07-06 N4401L MLY → FAI Jul 6, 19:30 UTCJul 6, 20:25 UTC55m
2026-07-06 N4401L FAI → MLY Jul 6, 17:15 UTCJul 6, 18:05 UTC50m
2026-07-06 N4401L - Jul 6, 00:15 UTCJul 6, 01:15 UTC1h 0m
2026-07-05 N4401L - Jul 5, 21:20 UTCJul 5, 22:20 UTC1h 0m
2026-07-04 N4401L SKW → FAI Jul 4, 18:15 UTCJul 4, 20:30 UTC2h 15m
2026-07-03 N4401L FAI → SKW Jul 3, 22:55 UTCJul 4, 01:10 UTC2h 15m
2026-07-03 N4401L MLY → FAI Jul 3, 18:50 UTCJul 3, 19:35 UTC45m
2026-07-03 N4401L - Jul 3, 18:05 UTCJul 3, 18:15 UTC10m
2026-07-03 N4401L - Jul 3, 16:40 UTCJul 3, 17:30 UTC50m
2026-07-03 N4401L - Jul 3, 07:00 UTCJul 3, 07:25 UTC25m
2026-07-03 N4401L - Jul 3, 05:15 UTCJul 3, 05:55 UTC40m
2026-07-03 N4401L FAI → FAI Jul 3, 02:40 UTCJul 3, 03:35 UTC55m
2026-07-02 N4401L FAI → FAI Jul 2, 22:40 UTCJul 3, 00:25 UTC1h 45m

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 N4401L page for operator, model, and routing details .

Mode-S A54D23 frequently asked

What is Mode-S code A54D23?
A54D23 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N4401L.
Where is Mode-S A54D23 registered?
Mode-S code A54D23 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 A54D23 broadcasting right now?
No active broadcast right now. Last signal was 9h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A54D23, octal 51246443, decimal 10,833,187.
What flights does A54D23 operate?
Mode-S A54D23 has broadcast 1 distinct callsign, including N4401L.