sensors Mode-S transponder

A9F75F

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N741ML · PIPISTREL Alpha Trainer · operated by SIERRA NEVADA FLYERS LLC

Hex
A9F75F
Octal
52373537
Decimal
11,138,911
Country
US
Tail
N741ML
Type
PIAT
No current signal · last broadcast 8d ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
8d ago

Last known position

Most recent position reported by Mode-S A9F75F.

Country allocation

The ICAO 24-bit address A9F75F 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
N741ML - 5 2026-05-21

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-05-21 N741ML - May 21, 17:45 UTCMay 21, 18:25 UTC40m
2026-05-21 N741ML - May 21, 16:20 UTCMay 21, 16:55 UTC35m
2026-05-21 N741ML AUN → AUN May 21, 15:40 UTCMay 21, 15:50 UTC10m
2026-05-13 N741ML - May 13, 18:00 UTCMay 13, 18:40 UTC40m
2026-05-13 N741ML AUN → AUN May 13, 14:15 UTCMay 13, 14:30 UTC15m

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 N741ML page for operator, model, and routing details .

Mode-S A9F75F frequently asked

What is Mode-S code A9F75F?
A9F75F is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N741ML.
Where is Mode-S A9F75F registered?
Mode-S code A9F75F 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 A9F75F broadcasting right now?
No active broadcast right now. Last signal was 8d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9F75F, octal 52373537, decimal 11,138,911.
What flights does A9F75F operate?
Mode-S A9F75F has broadcast 1 distinct callsign, including N741ML.