sensors Mode-S transponder

A4EFDB

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N417TS · DIAMOND DA-42 Guardian · operated by NYMOON LLC

Hex
A4EFDB
Octal
51167733
Decimal
10,809,307
Country
US
Tail
N417TS
Type
DA42
No current signal · last broadcast 3h ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S A4EFDB.

Country allocation

The ICAO 24-bit address A4EFDB 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
N417TS - 5 2026-04-21

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-21 N417TS - Apr 21, 03:25 UTCApr 21, 04:20 UTC55m
2026-04-20 N417TS - Apr 20, 23:35 UTCApr 21, 00:35 UTC1h 0m
2026-04-17 N417TS - Apr 17, 01:20 UTCApr 17, 02:30 UTC1h 10m
2026-04-15 N417TS - Apr 15, 23:50 UTCApr 16, 01:05 UTC1h 15m
2026-04-13 N417TS - Apr 13, 23:10 UTCApr 13, 23:40 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 N417TS page for operator, model, and routing details .

Mode-S A4EFDB frequently asked

What is Mode-S code A4EFDB?
A4EFDB is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N417TS.
Where is Mode-S A4EFDB registered?
Mode-S code A4EFDB 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 A4EFDB broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4EFDB, octal 51167733, decimal 10,809,307.
What flights does A4EFDB operate?
Mode-S A4EFDB has broadcast 1 distinct callsign, including N417TS.