Mode-S ADFF73 · Transponder Hex for 66-4358

Q: What is Mode-S code ADFF73?

ADFF73 is an ICAO 24-bit transponder address. Assigned to 66-4358 .

Last known position

Most recent position reported by Mode-S ADFF73.

Callsign history 4 distinct

Callsign	Airline	Flights	Last seen
SPEED44	-	1	2026-04-14
GUNDOG1	-	1	2026-04-15
EAGLE41	-	1	2026-04-13
BASS32	-	1	2026-04-14

Recent flights last 4

Date	Flight	Route	Takeoff	Landing	Duration
2026-04-15	GUNDOG1	-	Apr 15, 17:50 UTC	Apr 15, 18:05 UTC	15m
2026-04-14	BASS32	-	Apr 14, 20:20 UTC	Apr 14, 20:40 UTC	20m
2026-04-14	SPEED44	-	Apr 14, 17:40 UTC	Apr 14, 18:00 UTC	20m
2026-04-13	EAGLE41	-	Apr 13, 20:40 UTC	Apr 13, 21:15 UTC	35m

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 66-4358 page for operator, model, and routing details .

Mode-S ADFF73 frequently asked

What is Mode-S code ADFF73?

ADFF73 is an ICAO 24-bit transponder address. Assigned to 66-4358.

Is ADFF73 broadcasting right now?

No active broadcast right now. Last signal was 3d ago.

Hex, octal, and decimal Mode-S codes: what's the difference?

The same 24-bit identifier expressed in different bases: hex ADFF73, octal 53377563, decimal 11,403,123.

What flights does ADFF73 operate?

Mode-S ADFF73 has broadcast 4 distinct callsigns, including SPEED44, GUNDOG1, EAGLE41, BASS32.