Apparatus

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sensors Mode-S transponder

AAC1F1

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N7921C · ROBINSON R-44 Raven · operated by BROWN JACK PDBA, LJB AIR SERVICE

Hex
AAC1F1
Octal
52540761
Decimal
11,190,769
Country
US
Tail
N7921C
Type
R44
No current signal · last broadcast 11h ago
Flights observed
76
Distinct callsigns
1
Country
US
Last broadcast
11h ago

Last known position

Most recent position reported by Mode-S AAC1F1.

Country allocation

The ICAO 24-bit address AAC1F1 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
N7921C - 76 2026-07-14

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 N7921C - Jul 14, 02:25 UTCJul 14, 02:40 UTC15m
2026-07-14 N7921C - Jul 14, 01:10 UTCJul 14, 01:20 UTC10m
2026-07-12 N7921C - Jul 12, 15:40 UTCJul 12, 18:05 UTC2h 25m
2026-07-12 N7921C - Jul 12, 01:00 UTCJul 12, 01:30 UTC30m
2026-07-11 N7921C - Jul 11, 14:35 UTCJul 11, 15:20 UTC45m
2026-07-10 N7921C - Jul 10, 17:30 UTCJul 10, 20:45 UTC3h 15m
2026-07-10 N7921C - Jul 10, 16:25 UTCJul 10, 16:45 UTC20m
2026-07-08 N7921C - Jul 8, 17:00 UTCJul 9, 00:10 UTC7h 10m
2026-07-07 N7921C - Jul 7, 20:00 UTCJul 7, 20:45 UTC45m
2026-07-07 N7921C - Jul 7, 15:40 UTCJul 7, 17:15 UTC1h 35m
2026-07-07 N7921C - Jul 7, 02:55 UTCJul 7, 03:10 UTC15m
2026-07-06 N7921C - Jul 6, 19:55 UTCJul 6, 20:25 UTC30m
2026-07-03 N7921C - Jul 3, 01:00 UTCJul 3, 02:35 UTC1h 35m
2026-07-02 N7921C - Jul 2, 23:30 UTCJul 2, 23:50 UTC20m
2026-07-02 N7921C - Jul 2, 22:00 UTCJul 2, 22:25 UTC25m
2026-07-02 N7921C - Jul 2, 19:55 UTCJul 2, 20:55 UTC1h 0m
2026-07-02 N7921C - Jul 2, 18:50 UTCJul 2, 19:25 UTC35m
2026-07-02 N7921C - Jul 2, 17:40 UTCJul 2, 17:50 UTC10m
2026-07-02 N7921C - Jul 2, 16:05 UTCJul 2, 16:40 UTC35m
2026-06-30 N7921C - Jun 30, 00:04 UTCJun 30, 00:20 UTC15m
2026-06-27 N7921C - Jun 27, 16:44 UTCJun 27, 17:55 UTC1h 10m
2026-06-27 N7921C - Jun 27, 13:44 UTCJun 27, 14:20 UTC35m
2026-06-26 N7921C - Jun 26, 23:25 UTCJun 27, 00:55 UTC1h 30m
2026-06-26 N7921C - Jun 26, 20:55 UTCJun 26, 21:35 UTC40m
2026-06-25 N7921C - Jun 25, 21:35 UTCJun 25, 22:34 UTC1h 0m
2026-06-25 N7921C - Jun 25, 16:45 UTCJun 25, 18:00 UTC1h 15m
2026-06-17 N7921C - Jun 17, 00:25 UTCJun 17, 00:50 UTC25m
2026-06-16 N7921C - Jun 16, 16:05 UTCJun 16, 16:25 UTC20m
2026-06-16 N7921C - Jun 16, 01:04 UTCJun 16, 01:15 UTC10m
2026-06-16 N7921C - Jun 16, 00:05 UTCJun 16, 00:24 UTC20m
2026-06-15 N7921C - Jun 15, 20:59 UTCJun 15, 22:05 UTC1h 5m
2026-06-15 N7921C - Jun 15, 19:05 UTCJun 15, 19:30 UTC25m
2026-06-15 N7921C - Jun 15, 17:10 UTCJun 15, 17:34 UTC25m
2026-06-14 N7921C - Jun 14, 22:50 UTCJun 14, 23:50 UTC1h 0m
2026-06-14 N7921C - Jun 14, 14:40 UTCJun 14, 16:10 UTC1h 30m
2026-06-13 N7921C - Jun 13, 23:35 UTCJun 14, 00:30 UTC55m
2026-06-09 N7921C - Jun 9, 23:15 UTCJun 10, 00:35 UTC1h 20m
2026-06-09 N7921C CKU → CKU Jun 9, 21:00 UTCJun 9, 21:25 UTC25m
2026-06-09 N7921C CKU → CKU Jun 9, 19:20 UTCJun 9, 19:55 UTC35m
2026-06-09 N7921C - Jun 9, 17:25 UTCJun 9, 18:00 UTC35m
2026-06-05 N7921C - Jun 5, 23:05 UTCJun 6, 00:40 UTC1h 35m
2026-06-05 N7921C - Jun 5, 21:45 UTCJun 5, 22:30 UTC45m
2026-06-05 N7921C - Jun 5, 15:00 UTCJun 5, 15:30 UTC30m
2026-06-05 N7921C - Jun 5, 00:25 UTCJun 5, 00:50 UTC25m
2026-06-04 N7921C - Jun 4, 16:50 UTCJun 4, 17:05 UTC15m
2026-06-04 N7921C - Jun 4, 15:00 UTCJun 4, 15:35 UTC35m
2026-06-04 N7921C - Jun 4, 04:30 UTCJun 4, 06:45 UTC2h 15m
2026-06-04 N7921C - Jun 4, 00:30 UTCJun 4, 03:35 UTC3h 5m
2026-06-03 N7921C - Jun 3, 15:00 UTCJun 3, 15:30 UTC30m
2026-06-03 N7921C - Jun 3, 00:35 UTCJun 3, 00:55 UTC20m

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 N7921C page for operator, model, and routing details .

Mode-S AAC1F1 frequently asked

What is Mode-S code AAC1F1?
AAC1F1 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N7921C.
Where is Mode-S AAC1F1 registered?
Mode-S code AAC1F1 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 AAC1F1 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 AAC1F1, octal 52540761, decimal 11,190,769.
What flights does AAC1F1 operate?
Mode-S AAC1F1 has broadcast 1 distinct callsign, including N7921C.