sensors Mode-S transponder

A15EFD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N188GC · CESSNA 208 Caravan · operated by ZUNI LLC

Hex
A15EFD
Octal
50257375
Decimal
10,575,613
Country
US
Tail
N188GC
Type
C208
No current signal · last broadcast 7m ago
Flights observed
13
Distinct callsigns
1
Country
US
Last broadcast
7m ago

Last known position

Most recent position reported by Mode-S A15EFD.

Country allocation

The ICAO 24-bit address A15EFD 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
CVU88 - 13 2026-06-11

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-06-11 CVU88 - Jun 11, 18:50 UTCJun 11, 19:15 UTC25m
2026-06-11 CVU88 - Jun 11, 17:50 UTCJun 11, 18:15 UTC25m
2026-06-11 CVU88 - Jun 11, 16:50 UTCJun 11, 17:15 UTC25m
2026-06-11 CVU88 - Jun 11, 15:20 UTCJun 11, 16:15 UTC55m
2026-06-11 CVU88 - Jun 11, 01:05 UTCJun 11, 01:25 UTC20m
2026-06-10 CVU88 - Jun 10, 23:20 UTCJun 10, 23:40 UTC20m
2026-06-10 CVU88 - Jun 10, 22:00 UTCJun 10, 22:25 UTC25m
2026-06-10 CVU88 - Jun 10, 20:50 UTCJun 10, 21:15 UTC25m
2026-06-10 CVU88 - Jun 10, 19:15 UTCJun 10, 19:35 UTC20m
2026-06-10 CVU88 - Jun 10, 17:00 UTCJun 10, 17:20 UTC20m
2026-06-10 CVU88 - Jun 10, 15:45 UTCJun 10, 16:05 UTC20m
2026-06-10 CVU88 - Jun 10, 14:50 UTCJun 10, 15:15 UTC25m
2026-06-09 CVU88 - Jun 9, 19:20 UTCJun 9, 19:35 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 N188GC page for operator, model, and routing details .

Mode-S A15EFD frequently asked

What is Mode-S code A15EFD?
A15EFD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N188GC.
Where is Mode-S A15EFD registered?
Mode-S code A15EFD 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 A15EFD broadcasting right now?
No active broadcast right now. Last signal was 7m ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A15EFD, octal 50257375, decimal 10,575,613.
What flights does A15EFD operate?
Mode-S A15EFD has broadcast 1 distinct callsign, including CVU88.