sensors Mode-S transponder

AF4FAB

ICAO 24-bit transponder address

Currently assigned to 24-21300 · SIKORSKY UH-60 Black Hawk

Hex
AF4FAB
Octal
53647653
Decimal
11,489,195
Tail
24-21300
Type
H60
No current signal · last broadcast 13d ago
Flights observed
6
Distinct callsigns
4
Country
-
Last broadcast
13d ago

Last known position

Most recent position reported by Mode-S AF4FAB.

Callsign history 4 distinct

Callsign Airline Flights Last seen
BELLS76 - 3 2026-05-20
TALON89 - 1 2026-04-23
GC0300 - 1 2026-05-08
BELLS70 - 1 2026-05-20

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-05-20 BELLS76 - May 20, 18:20 UTCMay 20, 19:45 UTC1h 25m
2026-05-20 BELLS76 BFK → BFK May 20, 17:55 UTCMay 20, 18:15 UTC20m
2026-05-20 BELLS70 BFK → BFK May 20, 00:55 UTCMay 20, 02:35 UTC1h 40m
2026-05-15 BELLS76 - May 15, 21:55 UTCMay 15, 22:40 UTC45m
2026-05-08 GC0300 - May 8, 17:35 UTCMay 8, 18:30 UTC55m
2026-04-23 TALON89 - Apr 23, 20:05 UTCApr 23, 20:15 UTC10m

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 24-21300 page for operator, model, and routing details .

Mode-S AF4FAB frequently asked

What is Mode-S code AF4FAB?
AF4FAB is an ICAO 24-bit transponder address. Assigned to 24-21300.
Is AF4FAB broadcasting right now?
No active broadcast right now. Last signal was 13d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AF4FAB, octal 53647653, decimal 11,489,195.
What flights does AF4FAB operate?
Mode-S AF4FAB has broadcast 4 distinct callsigns, including BELLS76, TALON89, GC0300, BELLS70.