sensors Mode-S transponder

A1CD1D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N215LP · CESSNA 172 Skyhawk · operated by CHRISTIANSEN AVIATION LLC

Hex
A1CD1D
Octal
50346435
Decimal
10,603,805
Country
US
Tail
N215LP
Type
C172
Broadcasting now · callsign N215LP · 5,375 ft
Flights observed
4
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Current position

A1CD1D is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A1CD1D 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
N215LP - 4 2026-04-13

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-13 N215LP - Apr 13, 21:15 UTCApr 13, 22:40 UTC1h 25m
2026-04-13 N215LP - Apr 13, 14:35 UTCApr 13, 15:00 UTC25m
2026-04-12 N215LP TTN → TTN Apr 12, 18:30 UTCApr 12, 19:55 UTC1h 25m
2026-04-12 N215LP PNE → TTN Apr 12, 17:15 UTCApr 12, 17:35 UTC20m

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 N215LP page for operator, model, and routing details .

Mode-S A1CD1D frequently asked

What is Mode-S code A1CD1D?
A1CD1D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N215LP.
Where is Mode-S A1CD1D registered?
Mode-S code A1CD1D 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 A1CD1D broadcasting right now?
Yes. Mode-S A1CD1D is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1CD1D, octal 50346435, decimal 10,603,805.
What flights does A1CD1D operate?
Mode-S A1CD1D has broadcast 1 distinct callsign, including N215LP.