sensors Mode-S transponder

A1AD1F

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N207MH · BELL 206 JetRanger · operated by MERIDIAN HELICOPTERS LLC

Hex
A1AD1F
Octal
50326437
Decimal
10,595,615
Country
US
Tail
N207MH
Type
B06
No current signal · last broadcast 1d ago
Flights observed
4
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A1AD1F.

Country allocation

The ICAO 24-bit address A1AD1F 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
N207MH - 4 2026-04-13

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-13 N207MH - Apr 13, 23:15 UTCApr 13, 23:30 UTC15m
2026-04-13 N207MH - Apr 13, 22:10 UTCApr 13, 22:30 UTC20m
2026-04-13 N207MH - Apr 13, 00:30 UTCApr 13, 01:00 UTC30m
2026-04-12 N207MH BLM → BLM Apr 12, 18:00 UTCApr 12, 19:30 UTC1h 30m

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 N207MH page for operator, model, and routing details .

Mode-S A1AD1F frequently asked

What is Mode-S code A1AD1F?
A1AD1F is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N207MH.
Where is Mode-S A1AD1F registered?
Mode-S code A1AD1F 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 A1AD1F 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 A1AD1F, octal 50326437, decimal 10,595,615.
What flights does A1AD1F operate?
Mode-S A1AD1F has broadcast 1 distinct callsign, including N207MH.