sensors Mode-S transponder

A71D9D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N558EX · CESSNA 208 Caravan · operated by N558EX LLC

Hex
A71D9D
Octal
51616635
Decimal
10,952,093
Country
US
Tail
N558EX
Type
C208
Broadcasting now · callsign FIK558 · 6,625 ft
Flights observed
10
Distinct callsigns
1
Country
US
Last broadcast
1h ago

Current position

A71D9D is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A71D9D 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
FIK558 - 10 2026-05-09

Recent flights last 10

DateFlightRouteTakeoffLandingDuration
2026-05-09 FIK558 - May 9, 16:00 UTCMay 9, 18:10 UTC2h 10m
2026-05-07 FIK558 - May 7, 19:20 UTCMay 7, 20:10 UTC50m
2026-04-29 FIK558 - Apr 29, 20:05 UTCApr 29, 21:05 UTC1h 0m
2026-04-29 FIK558 - Apr 29, 16:55 UTCApr 29, 17:35 UTC40m
2026-04-29 FIK558 - Apr 29, 15:35 UTCApr 29, 16:10 UTC35m
2026-04-29 FIK558 - Apr 29, 12:10 UTCApr 29, 13:25 UTC1h 15m
2026-04-28 FIK558 - Apr 28, 19:55 UTCApr 28, 21:10 UTC1h 15m
2026-04-28 FIK558 - Apr 28, 18:05 UTCApr 28, 18:50 UTC45m
2026-04-25 FIK558 - Apr 25, 17:15 UTCApr 25, 17:55 UTC40m
2026-04-25 FIK558 - Apr 25, 15:20 UTCApr 25, 16:10 UTC50m

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 N558EX page for operator, model, and routing details .

Mode-S A71D9D frequently asked

What is Mode-S code A71D9D?
A71D9D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N558EX.
Where is Mode-S A71D9D registered?
Mode-S code A71D9D 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 A71D9D broadcasting right now?
Yes. Mode-S A71D9D is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A71D9D, octal 51616635, decimal 10,952,093.
What flights does A71D9D operate?
Mode-S A71D9D has broadcast 1 distinct callsign, including FIK558.