sensors Mode-S transponder

AAC4FD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N793US · DIAMOND DA-40 Club Star · operated by UTAH VALLEY UNIVERSITY

Hex
AAC4FD
Octal
52542375
Decimal
11,191,549
Country
US
Tail
N793US
Type
DA40
Broadcasting now · 5,550 ft
Flights observed
4
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Current position

AAC4FD is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address AAC4FD 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
N793US - 4 2026-04-13

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-13 N793US - Apr 13, 18:20 UTCApr 13, 19:05 UTC45m
2026-04-13 N793US - Apr 13, 16:15 UTCApr 13, 16:30 UTC15m
2026-04-13 N793US - Apr 13, 15:50 UTCApr 13, 16:30 UTC40m
2026-04-13 N793US - Apr 13, 15:35 UTCApr 13, 16:15 UTC40m

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 N793US page for operator, model, and routing details .

Mode-S AAC4FD frequently asked

What is Mode-S code AAC4FD?
AAC4FD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N793US.
Where is Mode-S AAC4FD registered?
Mode-S code AAC4FD 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 AAC4FD broadcasting right now?
Yes. Mode-S AAC4FD is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AAC4FD, octal 52542375, decimal 11,191,549.
What flights does AAC4FD operate?
Mode-S AAC4FD has broadcast 1 distinct callsign, including N793US.