sensors Mode-S transponder

A90938

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N681ZL · DASSAULT Falcon 2000 · operated by ZULU LIMA LLC

Hex
A90938
Octal
52204470
Decimal
11,077,944
Country
US
Tail
N681ZL
Type
F2TH
No current signal · last broadcast 4d ago
Flights observed
34
Distinct callsigns
3
Country
US
Last broadcast
4d ago

Last known position

Most recent position reported by Mode-S A90938.

Country allocation

The ICAO 24-bit address A90938 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 3 distinct

Callsign Airline Flights Last seen
CST41 - 18 2026-07-26
CST57 - 14 2026-07-18
N681ZL - 1 2026-05-16

Recent flights last 34

DateFlightRouteTakeoffLandingDuration
2026-07-26 CST41 - Jul 26, 17:05 UTCJul 26, 18:35 UTC1h 30m
2026-07-26 CST41 ANC → AKN Jul 26, 15:00 UTCJul 26, 15:45 UTC45m
2026-07-22 CST41 - Jul 22, 18:40 UTCJul 22, 19:25 UTC45m
2026-07-22 CST41 - Jul 22, 17:05 UTCJul 22, 17:55 UTC50m
2026-07-21 CST41 - Jul 21, 15:55 UTCJul 21, 22:30 UTC6h 35m
2026-07-21 CST41 - Jul 21, 14:25 UTCJul 21, 14:55 UTC30m
2026-07-21 CST41 - Jul 21, 11:50 UTCJul 21, 12:15 UTC25m
2026-07-18 CST57 - Jul 18, 16:30 UTCJul 18, 21:55 UTC5h 25m
2026-07-15 CST57 - Jul 15, 17:20 UTCJul 15, 22:40 UTC5h 20m
2026-07-06 CST41 - Jul 6, 15:00 UTCJul 6, 18:00 UTC3h 0m
2026-07-05 CST41 - Jul 5, 14:15 UTCJul 5, 17:00 UTC2h 45m
2026-06-28 CST41 - Jun 28, 00:15 UTCJun 28, 00:50 UTC35m
2026-06-27 CST41 TMB → HPN Jun 27, 19:55 UTCJun 27, 23:14 UTC3h 20m
2026-06-26 CST41 - Jun 26, 17:29 UTCJun 26, 20:00 UTC2h 30m
2026-06-26 CST41 - Jun 26, 14:39 UTCJun 26, 15:25 UTC45m
2026-06-24 CST41 - Jun 24, 22:49 UTCJun 24, 23:24 UTC35m
2026-06-24 CST41 - Jun 24, 16:50 UTCJun 24, 21:29 UTC4h 40m
2026-06-24 CST41 SJC → APC Jun 24, 14:55 UTCJun 24, 15:14 UTC20m
2026-06-20 CST41 - Jun 20, 04:04 UTCJun 20, 09:59 UTC5h 55m
2026-06-19 CST41 - Jun 19, 23:44 UTCJun 20, 00:39 UTC55m
2026-06-15 CST57 - Jun 15, 18:20 UTCJun 15, 19:50 UTC1h 30m
2026-06-15 CST57 - Jun 15, 13:00 UTCJun 15, 14:50 UTC1h 50m
2026-06-13 CST57 - Jun 13, 12:55 UTCJun 13, 15:35 UTC2h 40m
2026-05-16 N681ZL - May 16, 19:20 UTCMay 16, 19:55 UTC35m
2026-05-16 CST57 - May 16, 15:31 UTCMay 16, 18:00 UTC2h 30m
2026-05-13 CST57 - May 13, 15:50 UTCMay 13, 18:05 UTC2h 15m
2026-05-06 CST57 - May 6, 15:40 UTCMay 6, 18:15 UTC2h 34m
2026-05-01 - - May 1, 15:05 UTCMay 1, 17:30 UTC2h 25m
2026-04-26 CST57 - Apr 26, 15:40 UTCApr 26, 17:50 UTC2h 10m
2026-04-22 CST57 - Apr 22, 19:40 UTCApr 22, 22:25 UTC2h 45m
2026-04-22 CST57 PBI → BED Apr 22, 15:40 UTCApr 22, 18:25 UTC2h 45m
2026-04-19 CST57 - Apr 19, 18:15 UTCApr 19, 22:20 UTC4h 5m
2026-04-15 CST57 - Apr 15, 19:05 UTCApr 15, 20:55 UTC1h 50m
2026-04-15 CST57 - Apr 15, 17:05 UTCApr 15, 19:00 UTC1h 55m

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 N681ZL page for operator, model, and routing details .

Mode-S A90938 frequently asked

What is Mode-S code A90938?
A90938 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N681ZL.
Where is Mode-S A90938 registered?
Mode-S code A90938 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 A90938 broadcasting right now?
No active broadcast right now. Last signal was 4d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A90938, octal 52204470, decimal 11,077,944.
What flights does A90938 operate?
Mode-S A90938 has broadcast 3 distinct callsigns, including CST41, CST57, N681ZL.