sensors Mode-S transponder

A71648

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N556FX · BOMBARDIER BD-100 Challenger 300 · operated by FLEXJET LLC

Hex
A71648
Octal
51613110
Decimal
10,950,216
Country
US
Tail
N556FX
Type
CL30
No current signal · last broadcast 1d ago
Flights observed
6
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A71648.

Country allocation

The ICAO 24-bit address A71648 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
LXJ556 - 6 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 LXJ556 - Apr 13, 17:25 UTCApr 13, 18:35 UTC1h 10m
2026-04-13 LXJ556 - Apr 13, 15:50 UTCApr 13, 16:20 UTC30m
2026-04-13 LXJ556 - Apr 13, 15:35 UTCApr 13, 16:15 UTC40m
2026-04-13 LXJ556 - Apr 13, 01:10 UTCApr 13, 02:00 UTC50m
2026-04-12 LXJ556 - Apr 12, 23:55 UTCApr 13, 00:25 UTC30m
2026-04-12 LXJ556 - Apr 12, 17:35 UTCApr 12, 20:15 UTC2h 40m

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 N556FX page for operator, model, and routing details .

Mode-S A71648 frequently asked

What is Mode-S code A71648?
A71648 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N556FX.
Where is Mode-S A71648 registered?
Mode-S code A71648 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 A71648 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 A71648, octal 51613110, decimal 10,950,216.
What flights does A71648 operate?
Mode-S A71648 has broadcast 1 distinct callsign, including LXJ556.