sensors Mode-S transponder

ADF337

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N99832 · CESSNA 172 Skyhawk · operated by WATCH YA HEAD AVIATION 1 LLC

Hex
ADF337
Octal
53371467
Decimal
11,399,991
Country
US
Tail
N99832
Type
C172
No current signal · last broadcast 1d ago
Flights observed
3
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S ADF337.

Country allocation

The ICAO 24-bit address ADF337 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
N99832 - 3 2026-04-13

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-13 N99832 - Apr 13, 20:10 UTCApr 13, 21:10 UTC1h 0m
2026-04-13 N99832 - Apr 13, 18:05 UTCApr 13, 19:20 UTC1h 15m
2026-04-13 N99832 - Apr 13, 14:45 UTCApr 13, 15:50 UTC1h 5m

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 N99832 page for operator, model, and routing details .

Mode-S ADF337 frequently asked

What is Mode-S code ADF337?
ADF337 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N99832.
Where is Mode-S ADF337 registered?
Mode-S code ADF337 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 ADF337 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 ADF337, octal 53371467, decimal 11,399,991.
What flights does ADF337 operate?
Mode-S ADF337 has broadcast 1 distinct callsign, including N99832.