sensors Mode-S transponder

A503AD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N422GK · operated by CIRRUS DESIGN CORP

Hex
A503AD
Octal
51201655
Decimal
10,814,381
Country
US
Tail
N422GK
Type
SR22
No current signal · last broadcast 7d ago
Flights observed
11
Distinct callsigns
1
Country
US
Last broadcast
7d ago

Last known position

Most recent position reported by Mode-S A503AD.

Country allocation

The ICAO 24-bit address A503AD 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
N422GK - 11 2026-05-26

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-05-26 N422GK - May 26, 15:35 UTCMay 26, 15:45 UTC10m
2026-05-23 N422GK - May 23, 15:05 UTCMay 23, 16:55 UTC1h 50m
2026-05-22 N422GK - May 22, 15:20 UTCMay 22, 15:55 UTC35m
2026-05-19 N422GK - May 19, 14:35 UTCMay 19, 15:10 UTC35m
2026-05-18 N422GK - May 18, 15:20 UTCMay 18, 15:35 UTC15m
2026-05-13 N422GK AIK → AIK May 13, 18:55 UTCMay 13, 19:45 UTC50m
2026-05-06 N422GK AIK → AIK May 6, 18:05 UTCMay 6, 19:10 UTC1h 5m
2026-04-27 N422GK AIK → AIK Apr 27, 17:25 UTCApr 27, 18:20 UTC55m
2026-04-21 N422GK - Apr 21, 15:01 UTCApr 21, 17:45 UTC2h 45m
2026-04-19 N422GK - Apr 19, 15:05 UTCApr 19, 15:20 UTC15m
2026-04-17 N422GK - Apr 17, 11:25 UTCApr 17, 12:25 UTC1h 0m

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 N422GK page for operator, model, and routing details .

Mode-S A503AD frequently asked

What is Mode-S code A503AD?
A503AD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N422GK.
Where is Mode-S A503AD registered?
Mode-S code A503AD 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 A503AD broadcasting right now?
No active broadcast right now. Last signal was 7d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A503AD, octal 51201655, decimal 10,814,381.
What flights does A503AD operate?
Mode-S A503AD has broadcast 1 distinct callsign, including N422GK.