sensors Mode-S transponder

A7DC55

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N6051H · PIPER PA-32 · operated by FLYING SIX INC

Hex
A7DC55
Octal
51756125
Decimal
11,000,917
Country
US
Tail
N6051H
Type
PA32
No current signal · last broadcast Jul 21, 20:10 UTC
Flights observed
13
Distinct callsigns
1
Country
US
Last broadcast
Jul 21, 20:10 UTC

Last known position

Most recent position reported by Mode-S A7DC55.

Country allocation

The ICAO 24-bit address A7DC55 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
N6051H - 13 2026-07-21

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-07-21 N6051H - Jul 21, 18:40 UTCJul 21, 20:10 UTC1h 30m
2026-07-21 N6051H - Jul 21, 16:40 UTCJul 21, 17:20 UTC40m
2026-07-21 N6051H - Jul 21, 15:30 UTCJul 21, 15:55 UTC25m
2026-07-21 N6051H - Jul 21, 14:05 UTCJul 21, 14:30 UTC25m
2026-07-21 N6051H - Jul 21, 11:15 UTCJul 21, 13:20 UTC2h 5m
2026-06-24 N6051H - Jun 24, 15:29 UTCJun 24, 15:44 UTC15m
2026-06-22 N6051H - Jun 22, 23:10 UTCJun 22, 23:35 UTC25m
2026-05-19 N6051H - May 19, 19:30 UTCMay 19, 20:00 UTC30m
2026-05-19 N6051H - May 19, 15:20 UTCMay 19, 15:45 UTC25m
2026-05-18 N6051H - May 18, 14:20 UTCMay 18, 14:30 UTC10m
2026-05-10 N6051H - May 10, 20:25 UTCMay 10, 21:00 UTC35m
2026-05-06 N6051H - May 6, 20:20 UTCMay 6, 20:40 UTC20m
2026-04-14 N6051H - Apr 14, 18:30 UTCApr 14, 18:40 UTC10m

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 N6051H page for operator, model, and routing details .

Mode-S A7DC55 frequently asked

What is Mode-S code A7DC55?
A7DC55 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N6051H.
Where is Mode-S A7DC55 registered?
Mode-S code A7DC55 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 A7DC55 broadcasting right now?
No active broadcast right now. Last signal was Jul 21, 20:10 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A7DC55, octal 51756125, decimal 11,000,917.
What flights does A7DC55 operate?
Mode-S A7DC55 has broadcast 1 distinct callsign, including N6051H.