sensors Mode-S transponder

A15AAA

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N18698 · CESSNA 180 Skywagon · operated by LUMPKIN LARRY T

Hex
A15AAA
Octal
50255252
Decimal
10,574,506
Country
US
Tail
N18698
Type
C180
No current signal · last broadcast 1d ago
Flights observed
8
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A15AAA.

Country allocation

The ICAO 24-bit address A15AAA 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
N18698 - 8 2026-04-17

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-17 N18698 - Apr 17, 15:25 UTCApr 17, 17:15 UTC1h 50m
2026-04-17 N18698 - Apr 17, 14:05 UTCApr 17, 14:40 UTC35m
2026-04-16 N18698 - Apr 16, 17:44 UTCApr 16, 17:54 UTC10m
2026-04-16 N18698 - Apr 16, 15:15 UTCApr 16, 16:10 UTC55m
2026-04-16 N18698 - Apr 16, 14:35 UTCApr 16, 15:10 UTC35m
2026-04-16 N18698 - Apr 16, 13:44 UTCApr 16, 14:05 UTC20m
2026-04-14 N18698 - Apr 14, 11:20 UTCApr 14, 11:30 UTC10m
2026-04-13 N18698 - Apr 13, 11:15 UTCApr 13, 11:25 UTC10m

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 N18698 page for operator, model, and routing details .

Mode-S A15AAA frequently asked

What is Mode-S code A15AAA?
A15AAA is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N18698.
Where is Mode-S A15AAA registered?
Mode-S code A15AAA 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 A15AAA broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A15AAA, octal 50255252, decimal 10,574,506.
What flights does A15AAA operate?
Mode-S A15AAA has broadcast 1 distinct callsign, including N18698.