sensors Mode-S transponder

7C531C

ICAO 24-bit transponder address · allocated to Australia

Currently assigned to VH-QPA · AIRBUS A-330-300 · operated by QANTAS AIRWAYS LIMITED

Hex
7C531C
Octal
37051434
Decimal
8,147,740
Country
AU
Tail
VH-QPA
Type
A333
Photo of VH-QPA
No current signal · last broadcast 14h ago
Flights observed
2
Distinct callsigns
1
Country
AU
Last broadcast
14h ago

Last known position

Most recent position reported by Mode-S 7C531C.

Country allocation

The ICAO 24-bit address 7C531C falls within the block assigned to Australia (AU) by ICAO Annex 10, Volume III. Every aircraft registered in Australia 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
QFA127 Qantas 2 2026-04-14

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-14 QFA127 SYD → HKG Apr 14, 09:50 UTCApr 14, 10:20 UTC30m
2026-04-14 QFA127 SYD → HKG Apr 14, 08:25 UTCApr 14, 08:55 UTC30m

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 VH-QPA page for operator, model, and routing details .

Mode-S 7C531C frequently asked

What is Mode-S code 7C531C?
7C531C is an ICAO 24-bit transponder address. Allocated to Australia. Assigned to VH-QPA.
Where is Mode-S 7C531C registered?
Mode-S code 7C531C is allocated to Australia (AU). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 7C531C broadcasting right now?
No active broadcast right now. Last signal was 14h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 7C531C, octal 37051434, decimal 8,147,740.
What flights does 7C531C operate?
Mode-S 7C531C has broadcast 1 distinct callsign, including QFA127.