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sensors Mode-S transponder

A9E538

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N737BU · CESSNA 172 Skyhawk · operated by AERO EQUITIES LLC

Hex
A9E538
Octal
52362470
Decimal
11,134,264
Country
US
Tail
N737BU
Type
C172
No current signal · last broadcast Jul 26, 22:00 UTC
Flights observed
180
Distinct callsigns
1
Country
US
Last broadcast
Jul 26, 22:00 UTC

Last known position

Most recent position reported by Mode-S A9E538.

Country allocation

The ICAO 24-bit address A9E538 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
N737BU - 180 2026-07-26

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 N737BU - Jul 26, 21:30 UTCJul 26, 22:00 UTC30m
2026-07-26 N737BU BFL → BFL Jul 26, 20:40 UTCJul 26, 21:20 UTC40m
2026-07-26 N737BU - Jul 26, 19:30 UTCJul 26, 19:40 UTC10m
2026-07-26 N737BU - Jul 26, 16:55 UTCJul 26, 17:30 UTC35m
2026-07-26 N737BU BFL → BFL Jul 26, 15:45 UTCJul 26, 16:45 UTC1h 0m
2026-07-26 N737BU - Jul 26, 13:25 UTCJul 26, 15:10 UTC1h 45m
2026-07-25 N737BU BFL → BFL Jul 25, 21:20 UTCJul 25, 22:15 UTC55m
2026-07-25 N737BU - Jul 25, 20:45 UTCJul 25, 21:15 UTC30m
2026-07-25 N737BU BFL → BFL Jul 25, 18:30 UTCJul 25, 18:55 UTC25m
2026-07-25 N737BU BFL → BFL Jul 25, 17:55 UTCJul 25, 18:25 UTC30m
2026-07-25 N737BU BFL → BFL Jul 25, 15:40 UTCJul 25, 17:20 UTC1h 40m
2026-07-25 N737BU BFL → BFL Jul 25, 13:25 UTCJul 25, 14:50 UTC1h 25m
2026-07-24 N737BU - Jul 24, 21:50 UTCJul 24, 22:40 UTC50m
2026-07-24 N737BU BFL → BFL Jul 24, 20:40 UTCJul 24, 21:45 UTC1h 5m
2026-07-24 N737BU BFL → BFL Jul 24, 18:10 UTCJul 24, 19:05 UTC55m
2026-07-24 N737BU - Jul 24, 16:45 UTCJul 24, 17:25 UTC40m
2026-07-24 N737BU BFL → BFL Jul 24, 15:45 UTCJul 24, 16:25 UTC40m
2026-07-24 N737BU BFL → BFL Jul 24, 14:35 UTCJul 24, 15:40 UTC1h 5m
2026-07-24 N737BU BFL → BFL Jul 24, 13:25 UTCJul 24, 14:15 UTC50m
2026-07-23 N737BU BFL → BFL Jul 23, 22:00 UTCJul 23, 22:40 UTC40m
2026-07-23 N737BU BFL → BFL Jul 23, 20:55 UTCJul 23, 21:45 UTC50m
2026-07-23 N737BU BFL → BFL Jul 23, 18:05 UTCJul 23, 19:50 UTC1h 45m
2026-07-23 N737BU BFL → BFL Jul 23, 15:55 UTCJul 23, 17:10 UTC1h 15m
2026-07-23 N737BU - Jul 23, 14:25 UTCJul 23, 15:05 UTC40m
2026-07-23 N737BU BFL → BFL Jul 23, 13:20 UTCJul 23, 14:05 UTC45m
2026-07-22 N737BU MIT → BFL Jul 22, 22:05 UTCJul 22, 22:50 UTC45m
2026-07-22 N737BU - Jul 22, 20:55 UTCJul 22, 21:30 UTC35m
2026-07-22 N737BU BFL → BFL Jul 22, 16:50 UTCJul 22, 19:45 UTC2h 55m
2026-07-22 N737BU BFL → BFL Jul 22, 15:45 UTCJul 22, 16:30 UTC45m
2026-07-22 N737BU BFL → BFL Jul 22, 14:15 UTCJul 22, 15:10 UTC55m
2026-07-22 N737BU BFL → BFL Jul 22, 13:30 UTCJul 22, 14:10 UTC40m
2026-07-21 N737BU MIT → BFL Jul 21, 21:30 UTCJul 21, 22:30 UTC1h 0m
2026-07-21 N737BU BFL → MIT Jul 21, 20:40 UTCJul 21, 20:45 UTC5m
2026-07-21 N737BU BFL → BFL Jul 21, 15:15 UTCJul 21, 19:40 UTC4h 25m
2026-07-21 N737BU BFL → BFL Jul 21, 13:25 UTCJul 21, 15:10 UTC1h 45m
2026-07-13 N737BU - Jul 13, 21:50 UTCJul 13, 22:20 UTC30m
2026-07-13 N737BU - Jul 13, 20:50 UTCJul 13, 21:15 UTC25m
2026-07-13 N737BU BFL → BFL Jul 13, 13:15 UTCJul 13, 14:55 UTC1h 40m
2026-07-12 N737BU - Jul 12, 21:45 UTCJul 12, 22:25 UTC40m
2026-07-12 N737BU - Jul 12, 20:45 UTCJul 12, 21:10 UTC25m
2026-07-12 N737BU BFL → BFL Jul 12, 17:45 UTCJul 12, 19:30 UTC1h 45m
2026-07-12 N737BU - Jul 12, 15:50 UTCJul 12, 16:55 UTC1h 5m
2026-07-12 N737BU BFL → BFL Jul 12, 13:25 UTCJul 12, 15:05 UTC1h 40m
2026-07-11 N737BU - Jul 11, 15:40 UTCJul 11, 16:30 UTC50m
2026-07-11 N737BU - Jul 11, 14:15 UTCJul 11, 14:25 UTC10m
2026-07-09 N737BU - Jul 9, 18:45 UTCJul 9, 19:35 UTC50m
2026-07-09 N737BU - Jul 9, 14:05 UTCJul 9, 15:50 UTC1h 45m
2026-07-08 N737BU BFL → BFL Jul 8, 15:30 UTCJul 8, 16:05 UTC35m
2026-07-08 N737BU - Jul 8, 13:35 UTCJul 8, 14:10 UTC35m
2026-07-07 N737BU - Jul 7, 15:40 UTCJul 7, 16:15 UTC35m

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 N737BU page for operator, model, and routing details .

Mode-S A9E538 frequently asked

What is Mode-S code A9E538?
A9E538 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N737BU.
Where is Mode-S A9E538 registered?
Mode-S code A9E538 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 A9E538 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 22:00 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9E538, octal 52362470, decimal 11,134,264.
What flights does A9E538 operate?
Mode-S A9E538 has broadcast 1 distinct callsign, including N737BU.