sensors Mode-S transponder

A6FEBF

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N55TD · GULFSTREAM 4 · operated by AEROVISION-LOGOS AIRCRAFT HOLDINGS VII CORP

Hex
A6FEBF
Octal
51577277
Decimal
10,944,191
Country
US
Tail
N55TD
Type
GLF4
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 A6FEBF.

Country allocation

The ICAO 24-bit address A6FEBF 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
N55TD - 3 2026-04-13

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-13 N55TD - Apr 13, 21:15 UTCApr 13, 23:40 UTC2h 25m
2026-04-13 N55TD BED → BED Apr 13, 06:00 UTCApr 13, 06:15 UTC15m
2026-04-12 N55TD - Apr 12, 18:00 UTCApr 12, 20:15 UTC2h 15m

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 N55TD page for operator, model, and routing details .

Mode-S A6FEBF frequently asked

What is Mode-S code A6FEBF?
A6FEBF is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N55TD.
Where is Mode-S A6FEBF registered?
Mode-S code A6FEBF 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 A6FEBF 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 A6FEBF, octal 51577277, decimal 10,944,191.
What flights does A6FEBF operate?
Mode-S A6FEBF has broadcast 1 distinct callsign, including N55TD.