Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

00901B

ICAO 24-bit transponder address · allocated to South Africa

Currently assigned to ZS-GBY · SCHEIBE SF-25 Falke

Hex
00901B
Octal
00110033
Decimal
36,891
Country
ZA
Tail
ZS-GBY
Type
SF25
No current signal · last broadcast 4d ago
Flights observed
114
Distinct callsigns
1
Country
ZA
Last broadcast
4d ago

Last known position

Most recent position reported by Mode-S 00901B.

Country allocation

The ICAO 24-bit address 00901B falls within the block assigned to South Africa (ZA) by ICAO Annex 10, Volume III. Every aircraft registered in South Africa 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
ZSESW - 114 2026-05-29

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 ZSESW - May 29, 12:40 UTCMay 29, 12:55 UTC15m
2026-05-28 ZSESW - May 28, 11:35 UTCMay 28, 12:10 UTC35m
2026-05-28 ZSESW - May 28, 08:35 UTCMay 28, 10:00 UTC1h 25m
2026-05-28 ZSESW - May 28, 06:55 UTCMay 28, 07:50 UTC55m
2026-05-27 ZSESW - May 27, 14:25 UTCMay 27, 15:10 UTC45m
2026-05-27 ZSESW - May 27, 12:50 UTCMay 27, 13:30 UTC40m
2026-05-27 ZSESW - May 27, 10:50 UTCMay 27, 11:35 UTC45m
2026-05-27 ZSESW - May 27, 08:55 UTCMay 27, 09:40 UTC45m
2026-05-26 ZSESW - May 26, 14:45 UTCMay 26, 15:35 UTC50m
2026-05-26 ZSESW HLA → HLA May 26, 13:45 UTCMay 26, 14:05 UTC20m
2026-05-26 ZSESW - May 26, 12:35 UTCMay 26, 13:04 UTC30m
2026-05-25 ZSESW - May 25, 12:40 UTCMay 25, 13:55 UTC1h 15m
2026-05-25 ZSESW - May 25, 10:35 UTCMay 25, 11:35 UTC1h 0m
2026-05-25 ZSESW HLA → HLA May 25, 05:10 UTCMay 25, 06:10 UTC1h 0m
2026-05-24 ZSESW - May 24, 12:40 UTCMay 24, 13:35 UTC55m
2026-05-24 ZSESW - May 24, 08:40 UTCMay 24, 09:25 UTC45m
2026-05-24 ZSESW - May 24, 07:10 UTCMay 24, 08:00 UTC50m
2026-05-24 ZSESW HLA → HLA May 24, 05:25 UTCMay 24, 06:05 UTC40m
2026-05-23 ZSESW - May 23, 13:45 UTCMay 23, 14:15 UTC30m
2026-05-23 ZSESW - May 23, 11:20 UTCMay 23, 13:00 UTC1h 40m
2026-05-23 ZSESW - May 23, 08:55 UTCMay 23, 10:10 UTC1h 15m
2026-05-22 ZSESW - May 22, 15:10 UTCMay 22, 15:45 UTC35m
2026-05-22 ZSESW HLA → HLA May 22, 10:25 UTCMay 22, 11:35 UTC1h 10m
2026-05-22 ZSESW - May 22, 08:45 UTCMay 22, 09:45 UTC1h 0m
2026-05-22 ZSESW - May 22, 07:25 UTCMay 22, 07:55 UTC30m
2026-05-22 ZSESW - May 22, 05:35 UTCMay 22, 06:10 UTC35m
2026-05-21 ZSESW HLA → HLA May 21, 14:35 UTCMay 21, 15:30 UTC55m
2026-05-21 ZSESW HLA → HLA May 21, 12:40 UTCMay 21, 14:00 UTC1h 20m
2026-05-21 ZSESW - May 21, 10:55 UTCMay 21, 11:15 UTC20m
2026-05-21 ZSESW - May 21, 09:00 UTCMay 21, 09:15 UTC15m
2026-05-21 ZSESW HLA → HLA May 21, 07:15 UTCMay 21, 07:50 UTC35m
2026-05-21 ZSESW - May 21, 04:50 UTCMay 21, 05:45 UTC55m
2026-05-20 ZSESW - May 20, 14:55 UTCMay 20, 15:40 UTC45m
2026-05-20 ZSESW HLA → HLA May 20, 12:45 UTCMay 20, 14:15 UTC1h 30m
2026-05-20 ZSESW - May 20, 11:50 UTCMay 20, 12:00 UTC10m
2026-05-20 ZSESW HLA → HLA May 20, 10:55 UTCMay 20, 11:15 UTC20m
2026-05-20 ZSESW HLA → HLA May 20, 08:55 UTCMay 20, 09:55 UTC1h 0m
2026-05-20 ZSESW HLA → HLA May 20, 05:20 UTCMay 20, 06:15 UTC55m
2026-05-19 ZSESW - May 19, 15:05 UTCMay 19, 15:20 UTC15m
2026-05-15 ZSESW - May 15, 10:20 UTCMay 15, 11:10 UTC50m
2026-05-15 ZSESW - May 15, 07:20 UTCMay 15, 08:00 UTC40m
2026-05-14 ZSESW - May 14, 10:45 UTCMay 14, 11:05 UTC20m
2026-05-14 ZSESW - May 14, 08:55 UTCMay 14, 09:45 UTC50m
2026-05-14 ZSESW - May 14, 06:30 UTCMay 14, 07:40 UTC1h 10m
2026-05-14 ZSESW - May 14, 04:50 UTCMay 14, 05:30 UTC40m
2026-05-13 ZSESW - May 13, 17:50 UTCMay 13, 18:35 UTC45m
2026-05-13 ZSESW - May 13, 16:50 UTCMay 13, 17:10 UTC20m
2026-05-13 ZSESW - May 13, 14:51 UTCMay 13, 15:45 UTC55m
2026-05-13 ZSESW HLA → HLA May 13, 07:00 UTCMay 13, 07:35 UTC35m
2026-05-10 ZSESW - May 10, 09:05 UTCMay 10, 09:55 UTC50m

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 ZS-GBY page for operator, model, and routing details .

Mode-S 00901B frequently asked

What is Mode-S code 00901B?
00901B is an ICAO 24-bit transponder address. Allocated to South Africa. Assigned to ZS-GBY.
Where is Mode-S 00901B registered?
Mode-S code 00901B is allocated to South Africa (ZA). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 00901B broadcasting right now?
No active broadcast right now. Last signal was 4d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 00901B, octal 00110033, decimal 36,891.
What flights does 00901B operate?
Mode-S 00901B has broadcast 1 distinct callsign, including ZSESW.