sensors Mode-S transponder

AF9B91

ICAO 24-bit transponder address

Currently assigned to 23-14549 · SIKORSKY UH-60 Black Hawk

Hex
AF9B91
Octal
53715621
Decimal
11,508,625
Tail
23-14549
Type
H60
No current signal · last broadcast 11h ago
Flights observed
15
Distinct callsigns
0
Country
-
Last broadcast
11h ago

Last known position

Most recent position reported by Mode-S AF9B91.

Recent flights last 15

DateFlightRouteTakeoffLandingDuration
2026-06-02 - - Jun 2, 22:00 UTCJun 2, 22:10 UTC10m
2026-06-02 - - Jun 2, 19:15 UTCJun 2, 19:55 UTC40m
2026-05-20 - FRN → EDF May 20, 22:25 UTCMay 20, 22:35 UTC10m
2026-05-20 - EDF → FRN May 20, 19:50 UTCMay 20, 22:20 UTC2h 30m
2026-04-29 - - Apr 29, 21:45 UTCApr 29, 22:20 UTC35m
2026-04-23 - - Apr 23, 21:55 UTCApr 23, 22:25 UTC30m
2026-04-22 - - Apr 22, 21:55 UTCApr 22, 22:10 UTC15m
2026-04-22 - - Apr 22, 20:20 UTCApr 22, 21:00 UTC40m
2026-04-22 - - Apr 22, 20:00 UTCApr 22, 20:10 UTC10m
2026-04-17 - FRN → EDF Apr 17, 02:50 UTCApr 17, 03:15 UTC25m
2026-04-17 - EDF → FRN Apr 17, 02:35 UTCApr 17, 02:45 UTC10m
2026-04-17 - - Apr 17, 02:20 UTCApr 17, 02:30 UTC10m
2026-04-17 - - Apr 17, 01:20 UTCApr 17, 02:05 UTC45m
2026-04-16 - - Apr 16, 22:50 UTCApr 16, 23:00 UTC10m
2026-04-16 - - Apr 16, 21:14 UTCApr 16, 22:05 UTC50m

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 23-14549 page for operator, model, and routing details .

Mode-S AF9B91 frequently asked

What is Mode-S code AF9B91?
AF9B91 is an ICAO 24-bit transponder address. Assigned to 23-14549.
Is AF9B91 broadcasting right now?
No active broadcast right now. Last signal was 11h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AF9B91, octal 53715621, decimal 11,508,625.