sensors Mode-S transponder

04004B

ICAO 24-bit transponder address · allocated to Ethiopia

Currently assigned to ET-AOU · BOEING 787-8 Dreamliner

Hex
04004B
Octal
01000113
Decimal
262,219
Country
ET
Tail
ET-AOU
Type
B788
No current signal · last broadcast 18h ago
Flights observed
5
Distinct callsigns
3
Country
ET
Last broadcast
18h ago

Last known position

Most recent position reported by Mode-S 04004B.

Country allocation

The ICAO 24-bit address 04004B falls within the block assigned to Ethiopia (ET) by ICAO Annex 10, Volume III. Every aircraft registered in Ethiopia 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
ETH516 - 3 2026-04-13
ETH645 Ethiopian Airlines 1 2026-04-12
ETH517 - 1 2026-04-14

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-14 ETH517 - Apr 14, 08:25 UTCApr 14, 09:05 UTC40m
2026-04-13 ETH516 - Apr 13, 22:55 UTCApr 13, 23:40 UTC45m
2026-04-13 ETH516 - Apr 13, 15:50 UTCApr 13, 16:05 UTC15m
2026-04-13 ETH516 - Apr 13, 15:10 UTCApr 13, 16:05 UTC55m
2026-04-12 ETH645 HKG → ADD Apr 12, 18:50 UTCApr 12, 19:10 UTC20m

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 ET-AOU page for operator, model, and routing details .

Mode-S 04004B frequently asked

What is Mode-S code 04004B?
04004B is an ICAO 24-bit transponder address. Allocated to Ethiopia. Assigned to ET-AOU.
Where is Mode-S 04004B registered?
Mode-S code 04004B is allocated to Ethiopia (ET). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 04004B broadcasting right now?
No active broadcast right now. Last signal was 18h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 04004B, octal 01000113, decimal 262,219.
What flights does 04004B operate?
Mode-S 04004B has broadcast 3 distinct callsigns, including ETH516, ETH645, ETH517.