sensors Mode-S transponder

A4FA06

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N42HS · operated by VALIAIR LC TRUSTEE

Hex
A4FA06
Octal
51175006
Decimal
10,811,910
Country
US
Tail
N42HS
Type
HDJT
No current signal · last broadcast Jul 20, 15:45 UTC
Flights observed
11
Distinct callsigns
1
Country
US
Last broadcast
Jul 20, 15:45 UTC

Last known position

Most recent position reported by Mode-S A4FA06.

Country allocation

The ICAO 24-bit address A4FA06 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
N42HS - 11 2026-07-20

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-07-20 N42HS - Jul 20, 15:10 UTCJul 20, 15:45 UTC35m
2026-07-18 N42HS - Jul 18, 20:30 UTCJul 18, 21:20 UTC50m
2026-07-18 N42HS - Jul 18, 17:05 UTCJul 18, 19:55 UTC2h 50m
2026-07-18 N42HS - Jul 18, 13:35 UTCJul 18, 15:55 UTC2h 20m
2026-07-14 N42HS - Jul 14, 20:50 UTCJul 14, 21:30 UTC40m
2026-06-19 N42HS - Jun 19, 19:04 UTCJun 19, 19:45 UTC40m
2026-06-07 N42HS - Jun 7, 11:00 UTCJun 7, 11:40 UTC40m
2026-05-27 N42HS - May 27, 23:40 UTCMay 28, 00:25 UTC45m
2026-05-02 N42HS - May 2, 18:10 UTCMay 2, 18:30 UTC20m
2026-04-30 N42HS - Apr 30, 19:55 UTCApr 30, 21:30 UTC1h 35m
2026-04-30 N42HS - Apr 30, 18:15 UTCApr 30, 18:50 UTC35m

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 N42HS page for operator, model, and routing details .

Mode-S A4FA06 frequently asked

What is Mode-S code A4FA06?
A4FA06 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N42HS.
Where is Mode-S A4FA06 registered?
Mode-S code A4FA06 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 A4FA06 broadcasting right now?
No active broadcast right now. Last signal was Jul 20, 15:45 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4FA06, octal 51175006, decimal 10,811,910.
What flights does A4FA06 operate?
Mode-S A4FA06 has broadcast 1 distinct callsign, including N42HS.