sensors Mode-S transponder

A18EEF

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N2SP · BELL 429 GlobalRanger

Hex
A18EEF
Octal
50307357
Decimal
10,587,887
Country
US
Tail
N2SP
Type
B429
No current signal · last broadcast 1d ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A18EEF.

Country allocation

The ICAO 24-bit address A18EEF 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
N2SP - 5 2026-04-13

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-13 N2SP - Apr 13, 22:45 UTCApr 13, 23:00 UTC15m
2026-04-13 N2SP - Apr 13, 21:35 UTCApr 13, 22:25 UTC50m
2026-04-13 N2SP - Apr 13, 17:40 UTCApr 13, 18:50 UTC1h 10m
2026-04-13 N2SP - Apr 13, 15:10 UTCApr 13, 15:25 UTC15m
2026-04-13 N2SP - Apr 13, 06:40 UTCApr 13, 07:20 UTC40m

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 N2SP page for operator, model, and routing details .

Mode-S A18EEF frequently asked

What is Mode-S code A18EEF?
A18EEF is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N2SP.
Where is Mode-S A18EEF registered?
Mode-S code A18EEF 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 A18EEF 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 A18EEF, octal 50307357, decimal 10,587,887.
What flights does A18EEF operate?
Mode-S A18EEF has broadcast 1 distinct callsign, including N2SP.