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sensors Mode-S transponder

A5538E

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N442RM · operated by ROCKY MOUNTAIN COLLEGE

Hex
A5538E
Octal
51251616
Decimal
10,834,830
Country
US
Tail
N442RM
Type
PA44
No current signal · last broadcast Jul 20, 04:45 UTC
Flights observed
130
Distinct callsigns
1
Country
US
Last broadcast
Jul 20, 04:45 UTC

Last known position

Most recent position reported by Mode-S A5538E.

Country allocation

The ICAO 24-bit address A5538E 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
N442RM - 130 2026-07-20

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-20 N442RM - Jul 20, 04:25 UTCJul 20, 04:45 UTC20m
2026-07-19 N442RM - Jul 19, 14:25 UTCJul 19, 14:35 UTC10m
2026-07-18 N442RM - Jul 18, 15:10 UTCJul 18, 15:30 UTC20m
2026-07-16 N442RM - Jul 16, 15:35 UTCJul 16, 15:55 UTC20m
2026-07-15 N442RM - Jul 15, 14:50 UTCJul 15, 15:10 UTC20m
2026-07-15 N442RM - Jul 15, 13:05 UTCJul 15, 13:20 UTC15m
2026-07-14 N442RM - Jul 14, 18:25 UTCJul 14, 18:40 UTC15m
2026-07-14 N442RM - Jul 14, 14:40 UTCJul 14, 15:20 UTC40m
2026-07-14 N442RM - Jul 14, 12:40 UTCJul 14, 13:35 UTC55m
2026-07-13 N442RM - Jul 13, 14:35 UTCJul 13, 15:25 UTC50m
2026-07-13 N442RM - Jul 13, 13:15 UTCJul 13, 13:30 UTC15m
2026-07-13 N442RM - Jul 13, 11:35 UTCJul 13, 11:45 UTC10m
2026-07-12 N442RM - Jul 12, 12:40 UTCJul 12, 13:10 UTC30m
2026-07-11 N442RM - Jul 11, 14:50 UTCJul 11, 16:05 UTC1h 15m
2026-07-11 N442RM - Jul 11, 12:50 UTCJul 11, 13:05 UTC15m
2026-07-11 N442RM - Jul 11, 11:15 UTCJul 11, 11:50 UTC35m
2026-07-10 N442RM - Jul 10, 14:25 UTCJul 10, 14:35 UTC10m
2026-07-09 N442RM - Jul 9, 17:15 UTCJul 9, 17:40 UTC25m
2026-07-09 N442RM - Jul 9, 15:50 UTCJul 9, 16:10 UTC20m
2026-07-08 N442RM - Jul 8, 14:00 UTCJul 8, 14:45 UTC45m
2026-07-08 N442RM - Jul 8, 12:15 UTCJul 8, 12:25 UTC10m
2026-07-08 N442RM - Jul 8, 03:55 UTCJul 8, 04:15 UTC20m
2026-07-06 N442RM - Jul 6, 15:45 UTCJul 6, 16:00 UTC15m
2026-07-01 N442RM - Jul 1, 19:00 UTCJul 1, 20:00 UTC1h 0m
2026-06-29 N442RM - Jun 29, 13:30 UTCJun 29, 14:04 UTC35m
2026-06-28 N442RM - Jun 28, 15:20 UTCJun 28, 15:34 UTC15m
2026-06-26 N442RM - Jun 26, 16:44 UTCJun 26, 17:04 UTC20m
2026-06-26 N442RM - Jun 26, 15:15 UTCJun 26, 16:05 UTC50m
2026-06-24 N442RM - Jun 24, 17:20 UTCJun 24, 17:40 UTC20m
2026-06-24 N442RM - Jun 24, 15:24 UTCJun 24, 15:35 UTC10m
2026-06-24 N442RM - Jun 24, 12:50 UTCJun 24, 13:05 UTC15m
2026-06-23 N442RM - Jun 23, 22:10 UTCJun 23, 23:05 UTC55m
2026-06-20 N442RM - Jun 20, 16:14 UTCJun 20, 17:10 UTC55m
2026-06-19 N442RM - Jun 19, 17:09 UTCJun 19, 18:25 UTC1h 15m
2026-06-19 N442RM - Jun 19, 06:35 UTCJun 19, 06:44 UTC10m
2026-06-19 N442RM - Jun 19, 04:39 UTCJun 19, 04:50 UTC10m
2026-06-17 N442RM - Jun 17, 13:30 UTCJun 17, 13:40 UTC10m
2026-06-16 N442RM - Jun 16, 15:05 UTCJun 16, 15:20 UTC15m
2026-06-16 N442RM - Jun 16, 00:15 UTCJun 16, 00:35 UTC20m
2026-06-15 N442RM - Jun 15, 16:15 UTCJun 15, 17:04 UTC50m
2026-06-15 N442RM - Jun 15, 15:19 UTCJun 15, 15:30 UTC10m
2026-06-15 N442RM - Jun 15, 14:24 UTCJun 15, 14:45 UTC20m
2026-06-13 N442RM - Jun 13, 23:25 UTCJun 13, 23:40 UTC15m
2026-06-13 N442RM - Jun 13, 21:40 UTCJun 13, 22:15 UTC35m
2026-06-12 N442RM - Jun 12, 22:20 UTCJun 12, 23:15 UTC55m
2026-06-12 N442RM - Jun 12, 20:35 UTCJun 12, 20:50 UTC15m
2026-06-12 N442RM - Jun 12, 18:40 UTCJun 12, 19:35 UTC55m
2026-06-12 N442RM - Jun 12, 15:25 UTCJun 12, 15:45 UTC20m
2026-06-12 N442RM - Jun 12, 14:05 UTCJun 12, 14:15 UTC10m
2026-06-12 N442RM - Jun 12, 01:50 UTCJun 12, 02:35 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 N442RM page for operator, model, and routing details .

Mode-S A5538E frequently asked

What is Mode-S code A5538E?
A5538E is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N442RM.
Where is Mode-S A5538E registered?
Mode-S code A5538E 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 A5538E broadcasting right now?
No active broadcast right now. Last signal was Jul 20, 04:45 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A5538E, octal 51251616, decimal 10,834,830.
What flights does A5538E operate?
Mode-S A5538E has broadcast 1 distinct callsign, including N442RM.