sensors Mode-S transponder

A9B61F

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N725A · HUGHES Sky Knight · operated by ECHELON RIGHT LLC

Hex
A9B61F
Octal
52333037
Decimal
11,122,207
Country
US
Tail
N725A
Type
H269
No current signal · last broadcast 2d ago
Flights observed
1
Distinct callsigns
1
Country
US
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S A9B61F.

Country allocation

The ICAO 24-bit address A9B61F 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
N725A - 1 2026-04-12

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-04-12 N725A - Apr 12, 19:45 UTCApr 12, 20:10 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 N725A page for operator, model, and routing details .

Mode-S A9B61F frequently asked

What is Mode-S code A9B61F?
A9B61F is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N725A.
Where is Mode-S A9B61F registered?
Mode-S code A9B61F 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 A9B61F broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9B61F, octal 52333037, decimal 11,122,207.
What flights does A9B61F operate?
Mode-S A9B61F has broadcast 1 distinct callsign, including N725A.