sensors Mode-S transponder

A514C4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N42631 · CESSNA 182 Skylane · operated by GA ELITE LLC

Hex
A514C4
Octal
51212304
Decimal
10,818,756
Country
US
Tail
N42631
Type
C182
No current signal · last broadcast 5d ago
Flights observed
6
Distinct callsigns
1
Country
US
Last broadcast
5d ago

Last known position

Most recent position reported by Mode-S A514C4.

Country allocation

The ICAO 24-bit address A514C4 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
N42631 - 6 2026-05-17

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-05-17 N42631 - May 17, 22:05 UTCMay 17, 22:50 UTC45m
2026-05-15 N42631 - May 15, 23:35 UTCMay 16, 00:15 UTC40m
2026-04-19 N42631 - Apr 19, 21:45 UTCApr 19, 22:05 UTC20m
2026-04-19 N42631 SQL → SQA Apr 19, 19:25 UTCApr 19, 21:15 UTC1h 50m
2026-04-17 N42631 - Apr 17, 21:25 UTCApr 17, 21:45 UTC20m
2026-04-17 N42631 - Apr 17, 19:55 UTCApr 17, 21:20 UTC1h 25m

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 N42631 page for operator, model, and routing details .

Mode-S A514C4 frequently asked

What is Mode-S code A514C4?
A514C4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N42631.
Where is Mode-S A514C4 registered?
Mode-S code A514C4 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 A514C4 broadcasting right now?
No active broadcast right now. Last signal was 5d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A514C4, octal 51212304, decimal 10,818,756.
What flights does A514C4 operate?
Mode-S A514C4 has broadcast 1 distinct callsign, including N42631.