sensors Mode-S transponder

AC1846

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N879FD · BOEING 777-200LR · operated by FEDERAL EXPRESS CORP

Hex
AC1846
Octal
53014106
Decimal
11,278,406
Country
US
Tail
N879FD
Type
B77L
Photo of N879FD
Broadcasting now · callsign FDX5174 · 36,000 ft
Flights observed
7
Distinct callsigns
3
Country
US
Last broadcast
15h ago

Current position

AC1846 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address AC1846 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 3 distinct

Callsign Airline Flights Last seen
FDX5236 FedEx Express 3 2026-04-13
FDX5030 - 3 2026-04-14
FDX6015 - 1 2026-04-13

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-14 FDX5030 - Apr 14, 10:45 UTCApr 14, 11:05 UTC20m
2026-04-14 FDX5030 - Apr 14, 07:10 UTCApr 14, 08:05 UTC55m
2026-04-14 FDX5030 - Apr 14, 06:45 UTCApr 14, 07:10 UTC25m
2026-04-13 FDX6015 - Apr 13, 16:25 UTCApr 13, 17:05 UTC40m
2026-04-13 FDX5236 ANC → ICN Apr 13, 12:20 UTCApr 13, 14:15 UTC1h 55m
2026-04-13 FDX5236 ANC → ICN Apr 13, 12:05 UTCApr 13, 12:15 UTC10m
2026-04-13 FDX5236 ANC → ICN Apr 13, 05:21 UTCApr 13, 14:18 UTC8h 57m

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 N879FD page for operator, model, and routing details .

Mode-S AC1846 frequently asked

What is Mode-S code AC1846?
AC1846 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N879FD.
Where is Mode-S AC1846 registered?
Mode-S code AC1846 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 AC1846 broadcasting right now?
Yes. Mode-S AC1846 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AC1846, octal 53014106, decimal 11,278,406.
What flights does AC1846 operate?
Mode-S AC1846 has broadcast 3 distinct callsigns, including FDX5236, FDX5030, FDX6015.