sensors Mode-S transponder

A1D4AB

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N217MW · CESSNA 560XL Citation XLS · operated by WESTWINDS LLC

Hex
A1D4AB
Octal
50352253
Decimal
10,605,739
Country
US
Tail
N217MW
Type
C56X
No current signal · last broadcast 5h ago
Flights observed
73
Distinct callsigns
2
Country
US
Last broadcast
5h ago

Last known position

Most recent position reported by Mode-S A1D4AB.

Country allocation

The ICAO 24-bit address A1D4AB 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 2 distinct

Callsign Airline Flights Last seen
N517ME - 57 2026-07-06
N217MW - 16 2026-06-25

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-06 N517ME - Jul 6, 13:50 UTCJul 6, 14:30 UTC40m
2026-07-06 N517ME - Jul 6, 00:35 UTCJul 6, 02:40 UTC2h 5m
2026-07-02 N517ME - Jul 2, 16:00 UTCJul 2, 17:30 UTC1h 30m
2026-07-02 N517ME - Jul 2, 14:10 UTCJul 2, 14:40 UTC30m
2026-06-27 N517ME - Jun 27, 18:20 UTCJun 27, 19:00 UTC40m
2026-06-27 N517ME - Jun 27, 10:40 UTCJun 27, 11:09 UTC30m
2026-06-26 N517ME - Jun 26, 20:20 UTCJun 26, 20:44 UTC25m
2026-06-26 N517ME - Jun 26, 16:20 UTCJun 26, 17:25 UTC1h 5m
2026-06-26 N517ME - Jun 26, 14:09 UTCJun 26, 15:34 UTC1h 25m
2026-06-26 N517ME - Jun 26, 11:45 UTCJun 26, 12:50 UTC1h 5m
2026-06-25 N217MW - Jun 25, 20:49 UTCJun 25, 21:35 UTC45m
2026-06-25 N217MW - Jun 25, 19:20 UTCJun 25, 20:09 UTC50m
2026-06-24 N517ME - Jun 24, 21:24 UTCJun 25, 00:05 UTC2h 40m
2026-06-24 N517ME - Jun 24, 12:34 UTCJun 24, 15:00 UTC2h 25m
2026-06-24 N217MW - Jun 24, 11:09 UTCJun 24, 12:20 UTC1h 10m
2026-06-23 N517ME - Jun 23, 21:34 UTCJun 23, 22:34 UTC1h 0m
2026-06-22 N517ME - Jun 22, 19:09 UTCJun 22, 20:39 UTC1h 30m
2026-06-22 N517ME - Jun 22, 17:25 UTCJun 22, 18:24 UTC1h 0m
2026-06-21 N517ME - Jun 21, 20:50 UTCJun 21, 21:05 UTC15m
2026-06-21 N517ME - Jun 21, 19:09 UTCJun 21, 20:09 UTC1h 0m
2026-06-21 N517ME - Jun 21, 16:49 UTCJun 21, 18:00 UTC1h 10m
2026-06-21 N517ME - Jun 21, 14:44 UTCJun 21, 15:59 UTC1h 15m
2026-06-21 N517ME - Jun 21, 13:04 UTCJun 21, 13:39 UTC35m
2026-06-19 N517ME - Jun 19, 16:39 UTCJun 19, 17:49 UTC1h 10m
2026-06-19 N517ME - Jun 19, 14:09 UTCJun 19, 15:24 UTC1h 15m
2026-06-19 N517ME MTP → PVD Jun 19, 12:34 UTCJun 19, 12:49 UTC15m
2026-06-19 N517ME - Jun 19, 11:09 UTCJun 19, 12:29 UTC1h 20m
2026-06-18 N217MW - Jun 18, 20:30 UTCJun 18, 22:30 UTC2h 0m
2026-06-18 N217MW - Jun 18, 18:00 UTCJun 18, 18:10 UTC10m
2026-06-17 N517ME - Jun 17, 17:30 UTCJun 17, 18:56 UTC1h 25m
2026-06-17 N217MW - Jun 17, 14:40 UTCJun 17, 16:30 UTC1h 50m
2026-06-14 N517ME - Jun 14, 20:35 UTCJun 14, 21:10 UTC35m
2026-06-14 N517ME - Jun 14, 17:10 UTCJun 14, 19:35 UTC2h 25m
2026-06-11 N517ME - Jun 11, 20:55 UTCJun 11, 23:10 UTC2h 15m
2026-06-11 N517ME - Jun 11, 17:20 UTCJun 11, 18:00 UTC40m
2026-06-11 N517ME - Jun 11, 16:10 UTCJun 11, 16:35 UTC25m
2026-06-11 N517ME - Jun 11, 14:20 UTCJun 11, 14:30 UTC10m
2026-06-11 N517ME - Jun 11, 13:05 UTCJun 11, 13:30 UTC25m
2026-06-11 N517ME HAR → LNS Jun 11, 12:40 UTCJun 11, 12:50 UTC10m
2026-06-10 N217MW - Jun 10, 16:50 UTCJun 10, 18:30 UTC1h 40m
2026-06-10 N217MW - Jun 10, 11:00 UTCJun 10, 11:50 UTC50m
2026-06-09 N217MW - Jun 9, 16:45 UTCJun 9, 19:55 UTC3h 10m
2026-06-09 N217MW - Jun 9, 11:00 UTCJun 9, 12:20 UTC1h 20m
2026-06-03 N217MW - Jun 3, 18:35 UTCJun 3, 22:55 UTC4h 20m
2026-06-03 N517ME - Jun 3, 17:50 UTCJun 3, 18:10 UTC20m
2026-06-03 N217MW - Jun 3, 14:05 UTCJun 3, 14:40 UTC35m
2026-06-02 N217MW - Jun 2, 18:15 UTCJun 2, 20:30 UTC2h 15m
2026-06-02 N217MW CHA → APA Jun 2, 11:00 UTCJun 2, 13:45 UTC2h 45m
2026-06-01 N517ME - Jun 1, 23:50 UTCJun 2, 00:30 UTC40m
2026-06-01 N517ME - Jun 1, 21:45 UTCJun 1, 22:30 UTC45m

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 N217MW page for operator, model, and routing details .

Mode-S A1D4AB frequently asked

What is Mode-S code A1D4AB?
A1D4AB is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N217MW.
Where is Mode-S A1D4AB registered?
Mode-S code A1D4AB 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 A1D4AB broadcasting right now?
No active broadcast right now. Last signal was 5h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1D4AB, octal 50352253, decimal 10,605,739.
What flights does A1D4AB operate?
Mode-S A1D4AB has broadcast 2 distinct callsigns, including N517ME, N217MW.