sensors Mode-S transponder

A19D03

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N20289 · CESSNA 172 Skyhawk · operated by WHISKEY 36 LLC

Hex
A19D03
Octal
50316403
Decimal
10,591,491
Country
US
Tail
N20289
Type
C172
Broadcasting now · callsign N20289 · 1,000 ft
Flights observed
3
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Current position

A19D03 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A19D03 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
N20289 - 3 2026-04-13

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-13 N20289 - Apr 13, 12:55 UTCApr 13, 13:45 UTC50m
2026-04-12 N20289 - Apr 12, 18:40 UTCApr 12, 20:00 UTC1h 20m
2026-04-12 N20289 - Apr 12, 17:20 UTCApr 12, 17:50 UTC30m

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 N20289 page for operator, model, and routing details .

Mode-S A19D03 frequently asked

What is Mode-S code A19D03?
A19D03 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N20289.
Where is Mode-S A19D03 registered?
Mode-S code A19D03 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 A19D03 broadcasting right now?
Yes. Mode-S A19D03 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A19D03, octal 50316403, decimal 10,591,491.
What flights does A19D03 operate?
Mode-S A19D03 has broadcast 1 distinct callsign, including N20289.