sensors Mode-S transponder

A15D3D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N1871W · BEECH 95 Travel Air · operated by CITATIONXTANGO LLC

Hex
A15D3D
Octal
50256475
Decimal
10,575,165
Country
US
Tail
N1871W
Type
BE95
No current signal · last broadcast Jul 24, 03:10 UTC
Flights observed
11
Distinct callsigns
1
Country
US
Last broadcast
Jul 24, 03:10 UTC

Last known position

Most recent position reported by Mode-S A15D3D.

Country allocation

The ICAO 24-bit address A15D3D 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
N1871W - 11 2026-07-23

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-07-23 N1871W - Jul 23, 23:35 UTCJul 24, 03:10 UTC3h 35m
2026-07-18 N1871W - Jul 18, 11:25 UTCJul 18, 16:40 UTC5h 15m
2026-07-16 N1871W - Jul 16, 13:49 UTCJul 16, 16:00 UTC2h 10m
2026-07-13 N1871W - Jul 13, 14:15 UTCJul 13, 16:10 UTC1h 55m
2026-06-24 N1871W - Jun 24, 14:50 UTCJun 24, 15:05 UTC15m
2026-06-16 N1871W - Jun 16, 23:40 UTCJun 17, 00:00 UTC20m
2026-06-11 N1871W - Jun 11, 19:10 UTCJun 11, 19:35 UTC25m
2026-06-11 N1871W - Jun 11, 17:55 UTCJun 11, 18:05 UTC10m
2026-06-05 N1871W - Jun 5, 14:20 UTCJun 5, 14:45 UTC25m
2026-05-07 N1871W - May 7, 15:20 UTCMay 7, 15:40 UTC20m
2026-04-12 N1871W - Apr 12, 17:15 UTCApr 12, 18:55 UTC1h 40m

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 N1871W page for operator, model, and routing details .

Mode-S A15D3D frequently asked

What is Mode-S code A15D3D?
A15D3D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N1871W.
Where is Mode-S A15D3D registered?
Mode-S code A15D3D 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 A15D3D broadcasting right now?
No active broadcast right now. Last signal was Jul 24, 03:10 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A15D3D, octal 50256475, decimal 10,575,165.
What flights does A15D3D operate?
Mode-S A15D3D has broadcast 1 distinct callsign, including N1871W.