sensors Mode-S transponder

A2C25B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N277VC · CESSNA 525A Citation CJ2 · operated by 9012NEWHERE LLC

Hex
A2C25B
Octal
50541133
Decimal
10,666,587
Country
US
Tail
N277VC
Type
C25A
No current signal · last broadcast 11d ago
Flights observed
7
Distinct callsigns
1
Country
US
Last broadcast
11d ago

Last known position

Most recent position reported by Mode-S A2C25B.

Country allocation

The ICAO 24-bit address A2C25B falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States 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
N277VC - 7 2026-05-26

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-05-26 N277VC - May 26, 17:59 UTCMay 26, 18:50 UTC50m
2026-05-26 N277VC - May 26, 16:05 UTCMay 26, 17:09 UTC1h 5m
2026-05-19 N277VC - May 19, 15:30 UTCMay 19, 16:35 UTC1h 5m
2026-05-08 N277VC - May 8, 22:35 UTCMay 8, 22:45 UTC10m
2026-04-29 N277VC - Apr 29, 15:15 UTCApr 29, 17:01 UTC1h 45m
2026-04-29 N277VC - Apr 29, 00:25 UTCApr 29, 00:34 UTC10m
2026-04-22 N277VC - Apr 22, 14:20 UTCApr 22, 15:45 UTC1h 25m

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 N277VC page for operator, model, and routing details .

Mode-S A2C25B frequently asked

What is Mode-S code A2C25B?
A2C25B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N277VC.
Where is Mode-S A2C25B registered?
Mode-S code A2C25B is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is A2C25B broadcasting right now?
No active broadcast right now. Last signal was 11d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A2C25B, octal 50541133, decimal 10,666,587.
What flights does A2C25B operate?
Mode-S A2C25B has broadcast 1 distinct callsign, including N277VC.