sensors Mode-S transponder

4951CB

ICAO 24-bit transponder address · allocated to Portugal

Currently assigned to CS-TNK · AIRBUS A-320

Hex
4951CB
Octal
22250713
Decimal
4,805,067
Country
PT
Tail
CS-TNK
Type
A320
Photo of CS-TNK
No current signal · last broadcast 1d ago
Flights observed
6
Distinct callsigns
6
Country
PT
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 4951CB.

Country allocation

The ICAO 24-bit address 4951CB falls within the block assigned to Portugal (PT) by ICAO Annex 10, Volume III. Every aircraft registered in Portugal 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 6 distinct

Callsign Airline Flights Last seen
TAP93ZS - 1 2026-04-13
TAP932 - 1 2026-04-13
TAP56DP TAP Portugal 1 2026-04-13
TAP564C - 1 2026-04-12
TAP1902 - 1 2026-04-13
TAP1901 - 1 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 TAP93ZS - Apr 13, 16:40 UTCApr 13, 19:10 UTC2h 30m
2026-04-13 TAP932 - Apr 13, 12:45 UTCApr 13, 15:10 UTC2h 25m
2026-04-13 TAP1902 - Apr 13, 10:25 UTCApr 13, 11:00 UTC35m
2026-04-13 TAP1901 - Apr 13, 09:05 UTCApr 13, 09:35 UTC30m
2026-04-13 TAP56DP HAM → LIS Apr 13, 04:25 UTCApr 13, 07:30 UTC3h 5m
2026-04-12 TAP564C - Apr 12, 17:15 UTCApr 12, 20:00 UTC2h 45m

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 CS-TNK page for operator, model, and routing details .

Mode-S 4951CB frequently asked

What is Mode-S code 4951CB?
4951CB is an ICAO 24-bit transponder address. Allocated to Portugal. Assigned to CS-TNK.
Where is Mode-S 4951CB registered?
Mode-S code 4951CB is allocated to Portugal (PT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4951CB 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 4951CB, octal 22250713, decimal 4,805,067.
What flights does 4951CB operate?
Mode-S 4951CB has broadcast 6 distinct callsigns, including TAP93ZS, TAP932, TAP56DP, TAP564C, TAP1902.