Aircraft reference database • Mode-S / ICAO24

ICAO24 Aircraft Lookup.

Enter a six-character Mode-S hexadecimal address to identify the aircraft registration and, where preserved, its aircraft type, manufacturer, construction number and airline/operator.

What is an ICAO24 address?

From a hex code to the aircraft behind it.

An ICAO24 address is a 24-bit aircraft address normally written as six hexadecimal characters, for example 47161A. It is widely encountered in Mode-S and ADS-B receiver logs, flight-tracking software, SBS/BaseStation data and historical aircraft databases.

This lookup uses the restored ACARSd and libhomeradar reference data. The recovered 2008 snapshot alone contains almost 19,000 historical ICAO24-to-registration mappings, including aircraft that have since been retired, deregistered or disappeared from modern fleet lists.

Useful search terms

Mode-S hex code • ICAO24 address • aircraft registration • tail number • aircraft type • construction number • airline/operator

A Mode-S address or registration may have changed during an aircraft's lifetime, so old mappings are preserved rather than silently overwritten.

Have an aircraft registration instead? Open the Registration Lookup →

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AIRCRAFT RECORDS

Aircraft

B-18051

899021
Registration
B-18051
ICAO24 / Mode-S
899021
Manufacturer
Boeing
Aircraft type
777-36NER
Engine types
—
Year built
—
ICAO type
B77W
Construction number
41821 /1227
Operator
China Airlines
Operator codes
CAL
Aircraft country
—

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View all contacts with this aircraft recorded in the database →

ICAO24 result

899021 — 1 match

LAST 5 CONTACTS WITH THIS AIRCRAFT

Date / timeRegistrationFlightICAO24Label
2026-09-13 09:32:45 B-18051 CAL062 899021 ADSB
2026-09-13 04:21:28 B-18051 CAL061 899021 ADSB
2026-09-13 03:26:50 B-18051 — 899021 ADSB
2026-09-05 09:41:05 B-18051 CAL062 899021 ADSB
2026-09-05 05:33:00 B-18051 CAL061 899021 ADSB
About this database

An actively maintained aircraft reference database.

The ACARSd aircraft database is continuously maintained to keep its records up to date. New aircraft and ICAO24 mappings are added, existing entries are corrected and updated, and outdated entries are removed as needed.

Restored ACARSd data and historical Mode-S/ICAO24 mappings from the libhomeradar archive form part of its foundation.