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sensors Mode-S transponder

A121BE

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N172MR · CESSNA 172 Skyhawk · operated by GORGE WINDS AVIATION INC

Hex
A121BE
Octal
50220676
Decimal
10,559,934
Country
US
Tail
N172MR
Type
C172
No current signal · last broadcast 15h ago
Flights observed
230
Distinct callsigns
1
Country
US
Last broadcast
15h ago

Last known position

Most recent position reported by Mode-S A121BE.

Country allocation

The ICAO 24-bit address A121BE 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
N172MR - 230 2026-07-24

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-24 N172MR TTD → TTD Jul 24, 22:40 UTCJul 24, 22:50 UTC10m
2026-07-24 N172MR - Jul 24, 01:20 UTCJul 24, 02:15 UTC55m
2026-07-23 N172MR - Jul 23, 22:20 UTCJul 23, 23:20 UTC1h 0m
2026-07-23 N172MR TTD → TTD Jul 23, 19:20 UTCJul 23, 20:10 UTC50m
2026-07-21 N172MR TTD → TTD Jul 21, 20:10 UTCJul 21, 20:45 UTC35m
2026-07-21 N172MR - Jul 21, 17:25 UTCJul 21, 18:55 UTC1h 30m
2026-07-20 N172MR - Jul 20, 00:25 UTCJul 20, 01:05 UTC40m
2026-07-19 N172MR - Jul 19, 23:20 UTCJul 19, 23:40 UTC20m
2026-07-19 N172MR TTD → TTD Jul 19, 21:30 UTCJul 19, 22:20 UTC50m
2026-07-19 N172MR - Jul 19, 18:40 UTCJul 19, 19:55 UTC1h 15m
2026-07-18 N172MR TTD → TTD Jul 18, 22:10 UTCJul 18, 22:50 UTC40m
2026-07-18 N172MR - Jul 18, 19:50 UTCJul 18, 20:30 UTC40m
2026-07-18 N172MR - Jul 18, 17:30 UTCJul 18, 18:45 UTC1h 15m
2026-07-18 N172MR - Jul 18, 02:35 UTCJul 18, 03:10 UTC36m
2026-07-18 N172MR - Jul 18, 00:35 UTCJul 18, 01:05 UTC30m
2026-07-17 N172MR TTD → TTD Jul 17, 21:15 UTCJul 17, 22:15 UTC1h 0m
2026-07-17 N172MR - Jul 17, 19:40 UTCJul 17, 20:25 UTC45m
2026-07-17 N172MR TTD → TTD Jul 17, 17:05 UTCJul 17, 18:29 UTC1h 25m
2026-07-17 N172MR TTD → TTD Jul 17, 01:05 UTCJul 17, 02:05 UTC1h 0m
2026-07-16 N172MR TTD → TTD Jul 16, 21:10 UTCJul 16, 21:50 UTC40m
2026-07-15 N172MR - Jul 15, 21:20 UTCJul 15, 21:55 UTC35m
2026-07-15 N172MR - Jul 15, 18:45 UTCJul 15, 19:45 UTC1h 0m
2026-07-14 N172MR - Jul 14, 22:25 UTCJul 14, 23:40 UTC1h 14m
2026-07-14 N172MR TTD → TTD Jul 14, 19:35 UTCJul 14, 20:40 UTC1h 5m
2026-07-10 N172MR - Jul 10, 00:55 UTCJul 10, 02:00 UTC1h 5m
2026-07-09 N172MR - Jul 9, 22:35 UTCJul 9, 23:35 UTC1h 0m
2026-07-09 N172MR - Jul 9, 20:30 UTCJul 9, 21:45 UTC1h 15m
2026-07-09 N172MR - Jul 9, 16:10 UTCJul 9, 17:25 UTC1h 15m
2026-07-09 N172MR - Jul 9, 01:35 UTCJul 9, 01:55 UTC20m
2026-07-08 N172MR - Jul 8, 22:15 UTCJul 8, 23:35 UTC1h 20m
2026-07-08 N172MR - Jul 8, 20:30 UTCJul 8, 21:05 UTC35m
2026-07-08 N172MR TTD → TTD Jul 8, 17:35 UTCJul 8, 18:50 UTC1h 15m
2026-07-08 N172MR TTD → TTD Jul 8, 15:30 UTCJul 8, 16:35 UTC1h 5m
2026-07-08 N172MR - Jul 8, 01:10 UTCJul 8, 02:25 UTC1h 15m
2026-07-07 N172MR TTD → TTD Jul 7, 20:40 UTCJul 7, 21:35 UTC55m
2026-07-07 N172MR TTD → TTD Jul 7, 18:20 UTCJul 7, 19:30 UTC1h 10m
2026-07-06 N172MR - Jul 6, 22:55 UTCJul 6, 23:40 UTC45m
2026-07-06 N172MR - Jul 6, 21:45 UTCJul 6, 22:20 UTC35m
2026-07-06 N172MR TTD → TTD Jul 6, 00:45 UTCJul 6, 01:30 UTC45m
2026-07-05 N172MR - Jul 5, 21:30 UTCJul 5, 22:50 UTC1h 20m
2026-07-03 N172MR TTD → TTD Jul 3, 20:55 UTCJul 3, 22:35 UTC1h 40m
2026-07-03 N172MR - Jul 3, 17:25 UTCJul 3, 18:30 UTC1h 5m
2026-07-03 N172MR - Jul 3, 15:30 UTCJul 3, 16:05 UTC35m
2026-07-02 N172MR - Jul 2, 22:30 UTCJul 2, 23:35 UTC1h 5m
2026-07-02 N172MR - Jul 2, 20:40 UTCJul 2, 21:45 UTC1h 5m
2026-07-02 N172MR TTD → TTD Jul 2, 18:50 UTCJul 2, 19:55 UTC1h 5m
2026-07-02 N172MR - Jul 2, 15:45 UTCJul 2, 17:00 UTC1h 15m
2026-07-02 N172MR - Jul 2, 00:50 UTCJul 2, 01:55 UTC1h 5m
2026-07-01 N172MR - Jul 1, 21:55 UTCJul 1, 23:15 UTC1h 20m
2026-07-01 N172MR TTD → TTD Jul 1, 20:25 UTCJul 1, 21:10 UTC45m

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 N172MR page for operator, model, and routing details .

Mode-S A121BE frequently asked

What is Mode-S code A121BE?
A121BE is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N172MR.
Where is Mode-S A121BE registered?
Mode-S code A121BE 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 A121BE broadcasting right now?
No active broadcast right now. Last signal was 15h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A121BE, octal 50220676, decimal 10,559,934.
What flights does A121BE operate?
Mode-S A121BE has broadcast 1 distinct callsign, including N172MR.