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sensors Mode-S transponder

A9DBB4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N734UL · CESSNA 172 Skyhawk · operated by 734UL LLC

Hex
A9DBB4
Octal
52355664
Decimal
11,131,828
Country
US
Tail
N734UL
Type
C172
No current signal · last broadcast 6h ago
Flights observed
141
Distinct callsigns
1
Country
US
Last broadcast
6h ago

Last known position

Most recent position reported by Mode-S A9DBB4.

Country allocation

The ICAO 24-bit address A9DBB4 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
N734UL - 141 2026-07-17

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-17 N734UL - Jul 17, 14:39 UTCJul 17, 17:25 UTC2h 45m
2026-07-15 N734UL - Jul 15, 16:45 UTCJul 15, 17:40 UTC55m
2026-07-14 N734UL - Jul 14, 14:35 UTCJul 14, 15:40 UTC1h 5m
2026-07-13 N734UL - Jul 13, 14:40 UTCJul 13, 15:35 UTC55m
2026-07-12 N734UL - Jul 12, 20:50 UTCJul 12, 21:45 UTC55m
2026-07-11 N734UL - Jul 11, 21:20 UTCJul 11, 22:01 UTC40m
2026-07-11 N734UL - Jul 11, 19:00 UTCJul 11, 19:30 UTC30m
2026-07-11 N734UL - Jul 11, 16:55 UTCJul 11, 17:45 UTC50m
2026-07-10 N734UL - Jul 10, 21:00 UTCJul 10, 22:10 UTC1h 10m
2026-07-10 N734UL - Jul 10, 19:05 UTCJul 10, 20:05 UTC1h 0m
2026-07-10 N734UL - Jul 10, 14:30 UTCJul 10, 15:30 UTC1h 0m
2026-07-10 N734UL - Jul 10, 12:40 UTCJul 10, 13:40 UTC1h 0m
2026-07-09 N734UL - Jul 9, 23:20 UTCJul 10, 00:00 UTC40m
2026-07-09 N734UL - Jul 9, 19:40 UTCJul 9, 22:25 UTC2h 45m
2026-07-09 N734UL - Jul 9, 15:55 UTCJul 9, 17:30 UTC1h 35m
2026-07-09 N734UL - Jul 9, 14:40 UTCJul 9, 15:25 UTC45m
2026-07-08 N734UL - Jul 8, 23:05 UTCJul 8, 23:55 UTC50m
2026-07-08 N734UL - Jul 8, 21:10 UTCJul 8, 22:10 UTC1h 0m
2026-07-08 N734UL - Jul 8, 19:20 UTCJul 8, 20:20 UTC1h 0m
2026-07-08 N734UL - Jul 8, 16:35 UTCJul 8, 17:35 UTC1h 0m
2026-07-07 N734UL - Jul 7, 17:00 UTCJul 7, 18:55 UTC1h 55m
2026-07-07 N734UL - Jul 7, 14:55 UTCJul 7, 15:55 UTC1h 0m
2026-07-06 N734UL - Jul 6, 21:40 UTCJul 6, 22:15 UTC35m
2026-07-06 N734UL - Jul 6, 16:45 UTCJul 6, 17:15 UTC30m
2026-07-02 N734UL - Jul 2, 23:05 UTCJul 2, 23:50 UTC45m
2026-07-02 N734UL - Jul 2, 16:45 UTCJul 2, 17:10 UTC25m
2026-07-01 N734UL - Jul 1, 21:05 UTCJul 1, 22:10 UTC1h 5m
2026-07-01 N734UL - Jul 1, 16:40 UTCJul 1, 17:30 UTC50m
2026-06-30 N734UL - Jun 30, 16:40 UTCJun 30, 18:15 UTC1h 35m
2026-06-29 N734UL - Jun 29, 16:39 UTCJun 29, 17:30 UTC50m
2026-06-27 N734UL - Jun 27, 15:05 UTCJun 27, 15:49 UTC45m
2026-06-26 N734UL - Jun 26, 21:15 UTCJun 26, 22:10 UTC55m
2026-06-26 N734UL - Jun 26, 19:04 UTCJun 26, 20:10 UTC1h 5m
2026-06-26 N734UL - Jun 26, 14:29 UTCJun 26, 17:15 UTC2h 45m
2026-06-25 N734UL - Jun 25, 23:09 UTCJun 26, 00:05 UTC55m
2026-06-25 N734UL - Jun 25, 20:59 UTCJun 25, 22:10 UTC1h 10m
2026-06-25 N734UL - Jun 25, 18:55 UTCJun 25, 20:09 UTC1h 15m
2026-06-24 N734UL - Jun 24, 23:10 UTCJun 25, 00:09 UTC1h 0m
2026-06-24 N734UL - Jun 24, 19:15 UTCJun 24, 19:59 UTC45m
2026-06-24 N734UL - Jun 24, 14:50 UTCJun 24, 16:59 UTC2h 10m
2026-06-23 N734UL - Jun 23, 16:44 UTCJun 23, 18:14 UTC1h 30m
2026-06-22 N734UL - Jun 22, 21:10 UTCJun 22, 22:10 UTC1h 0m
2026-06-22 N734UL - Jun 22, 19:00 UTCJun 22, 20:19 UTC1h 20m
2026-06-19 N734UL - Jun 19, 20:04 UTCJun 19, 20:59 UTC55m
2026-06-18 N734UL - Jun 18, 23:20 UTCJun 19, 00:14 UTC54m
2026-06-18 N734UL - Jun 18, 21:00 UTCJun 18, 22:10 UTC1h 10m
2026-06-18 N734UL - Jun 18, 19:05 UTCJun 18, 20:20 UTC1h 15m
2026-06-18 N734UL - Jun 18, 16:25 UTCJun 18, 17:45 UTC1h 20m
2026-06-16 N734UL - Jun 16, 16:45 UTCJun 16, 17:15 UTC30m
2026-06-10 N734UL - Jun 10, 16:25 UTCJun 10, 17:45 UTC1h 20m

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 N734UL page for operator, model, and routing details .

Mode-S A9DBB4 frequently asked

What is Mode-S code A9DBB4?
A9DBB4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N734UL.
Where is Mode-S A9DBB4 registered?
Mode-S code A9DBB4 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 A9DBB4 broadcasting right now?
No active broadcast right now. Last signal was 6h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9DBB4, octal 52355664, decimal 11,131,828.
What flights does A9DBB4 operate?
Mode-S A9DBB4 has broadcast 1 distinct callsign, including N734UL.