sensors Mode-S transponder

A7009B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N550ND · CESSNA 172 Skyhawk · operated by PHOENIX EAST AVIATION LLC

Hex
A7009B
Octal
51600233
Decimal
10,944,667
Country
US
Tail
N550ND
Type
C172
No current signal · last broadcast 1d ago
Flights observed
7
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A7009B.

Country allocation

The ICAO 24-bit address A7009B 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
BPX261 - 7 2026-04-13

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-13 BPX261 - Apr 13, 19:50 UTCApr 13, 20:15 UTC25m
2026-04-13 BPX261 - Apr 13, 19:05 UTCApr 13, 20:10 UTC1h 5m
2026-04-13 BPX261 - Apr 13, 16:35 UTCApr 13, 17:50 UTC1h 15m
2026-04-13 BPX261 - Apr 13, 12:20 UTCApr 13, 13:05 UTC45m
2026-04-13 BPX261 - Apr 13, 12:00 UTCApr 13, 12:15 UTC15m
2026-04-12 BPX261 - Apr 12, 18:40 UTCApr 12, 19:20 UTC40m
2026-04-12 BPX261 - Apr 12, 17:25 UTCApr 12, 17:50 UTC25m

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 N550ND page for operator, model, and routing details .

Mode-S A7009B frequently asked

What is Mode-S code A7009B?
A7009B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N550ND.
Where is Mode-S A7009B registered?
Mode-S code A7009B 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 A7009B broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A7009B, octal 51600233, decimal 10,944,667.
What flights does A7009B operate?
Mode-S A7009B has broadcast 1 distinct callsign, including BPX261.