sensors Mode-S transponder

511121

ICAO 24-bit transponder address · allocated to Estonia

Currently assigned to 43 · PZL-MIELEC M-28 Skytruck

Hex
511121
Octal
24210441
Decimal
5,312,801
Country
EE
Tail
43
Type
M28
No current signal · last broadcast 1d ago
Flights observed
30
Distinct callsigns
1
Country
EE
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 511121.

Country allocation

The ICAO 24-bit address 511121 falls within the block assigned to Estonia (EE) by ICAO Annex 10, Volume III. Every aircraft registered in Estonia 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
EEF44 - 30 2026-07-16

Recent flights last 30

DateFlightRouteTakeoffLandingDuration
2026-07-16 EEF44 - Jul 16, 08:45 UTCJul 16, 12:05 UTC3h 20m
2026-07-15 EEF44 - Jul 15, 11:05 UTCJul 15, 11:25 UTC20m
2026-07-15 EEF44 - Jul 15, 09:25 UTCJul 15, 10:25 UTC1h 0m
2026-07-15 EEF44 - Jul 15, 07:25 UTCJul 15, 08:15 UTC50m
2026-07-14 EEF44 - Jul 14, 13:00 UTCJul 14, 13:25 UTC25m
2026-07-14 EEF44 - Jul 14, 11:35 UTCJul 14, 11:55 UTC20m
2026-07-14 EEF44 - Jul 14, 08:55 UTCJul 14, 10:10 UTC1h 15m
2026-07-14 EEF44 - Jul 14, 07:35 UTCJul 14, 07:55 UTC20m
2026-07-10 EEF44 - Jul 10, 09:00 UTCJul 10, 11:25 UTC2h 25m
2026-07-01 EEF44 - Jul 1, 11:45 UTCJul 1, 13:00 UTC1h 15m
2026-07-01 EEF44 - Jul 1, 07:50 UTCJul 1, 09:50 UTC2h 0m
2026-06-29 EEF44 - Jun 29, 09:25 UTCJun 29, 12:24 UTC3h 0m
2026-06-26 EEF44 - Jun 26, 07:14 UTCJun 26, 10:35 UTC3h 20m
2026-06-23 EEF44 - Jun 23, 08:35 UTCJun 23, 09:45 UTC1h 10m
2026-06-22 EEF44 - Jun 22, 14:10 UTCJun 22, 15:05 UTC55m
2026-06-22 EEF44 - Jun 22, 12:15 UTCJun 22, 13:35 UTC1h 20m
2026-06-20 EEF44 - Jun 20, 07:59 UTCJun 20, 09:59 UTC2h 0m
2026-06-19 EEF44 - Jun 19, 13:14 UTCJun 19, 15:14 UTC2h 0m
2026-06-19 EEF44 - Jun 19, 09:44 UTCJun 19, 11:49 UTC2h 5m
2026-06-19 EEF44 - Jun 19, 07:14 UTCJun 19, 08:59 UTC1h 45m
2026-06-18 EEF44 - Jun 18, 14:15 UTCJun 18, 16:15 UTC2h 0m
2026-06-18 EEF44 - Jun 18, 11:00 UTCJun 18, 13:05 UTC2h 5m
2026-06-18 EEF44 - Jun 18, 07:10 UTCJun 18, 09:25 UTC2h 15m
2026-06-17 EEF44 - Jun 17, 15:15 UTCJun 17, 16:15 UTC1h 0m
2026-06-17 EEF44 - Jun 17, 10:15 UTCJun 17, 11:30 UTC1h 15m
2026-06-16 EEF44 - Jun 16, 19:40 UTCJun 16, 20:45 UTC1h 6m
2026-06-16 EEF44 - Jun 16, 14:35 UTCJun 16, 16:25 UTC1h 50m
2026-06-16 EEF44 - Jun 16, 11:25 UTCJun 16, 12:55 UTC1h 30m
2026-05-14 EEF44 - May 14, 08:15 UTCMay 14, 11:30 UTC3h 15m
2026-05-11 EEF44 - May 11, 06:40 UTCMay 11, 07:40 UTC1h 0m

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 43 page for operator, model, and routing details .

Mode-S 511121 frequently asked

What is Mode-S code 511121?
511121 is an ICAO 24-bit transponder address. Allocated to Estonia. Assigned to 43.
Where is Mode-S 511121 registered?
Mode-S code 511121 is allocated to Estonia (EE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 511121 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 511121, octal 24210441, decimal 5,312,801.
What flights does 511121 operate?
Mode-S 511121 has broadcast 1 distinct callsign, including EEF44.