sensors Mode-S transponder

4D21A8

ICAO 24-bit transponder address · allocated to Malta

Currently assigned to 9H-DAD · DASSAULT Falcon 7X

Hex
4D21A8
Octal
23220650
Decimal
5,054,888
Country
MT
Tail
9H-DAD
Type
FA7X
Broadcasting now · callsign 9HDAD · 35,000 ft
Flights observed
5
Distinct callsigns
2
Country
MT
Last broadcast
2h ago

Current position

4D21A8 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4D21A8 falls within the block assigned to Malta (MT) by ICAO Annex 10, Volume III. Every aircraft registered in Malta 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
9HDAD - 3 2026-04-29
ALE701 - 2 2026-04-13

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-29 9HDAD - Apr 29, 14:35 UTCApr 29, 15:20 UTC45m
2026-04-17 9HDAD - Apr 17, 09:20 UTCApr 17, 10:00 UTC40m
2026-04-17 9HDAD - Apr 17, 07:35 UTCApr 17, 09:15 UTC1h 40m
2026-04-13 ALE701 - Apr 13, 08:20 UTCApr 13, 10:45 UTC2h 25m
2026-04-13 ALE701 - Apr 13, 08:00 UTCApr 13, 08:15 UTC15m

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 9H-DAD page for operator, model, and routing details .

Mode-S 4D21A8 frequently asked

What is Mode-S code 4D21A8?
4D21A8 is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-DAD.
Where is Mode-S 4D21A8 registered?
Mode-S code 4D21A8 is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D21A8 broadcasting right now?
Yes. Mode-S 4D21A8 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D21A8, octal 23220650, decimal 5,054,888.
What flights does 4D21A8 operate?
Mode-S 4D21A8 has broadcast 2 distinct callsigns, including 9HDAD, ALE701.