sensors Mode-S transponder

A6C9DD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N53656 · FAIRCHILD M-26 Cornell · operated by AMERICAN AIRPOWER HERITAGE FLYING MUSEUM

Hex
A6C9DD
Octal
51544735
Decimal
10,930,653
Country
US
Tail
N53656
Type
FA62
No current signal · last broadcast 2h ago
Flights observed
13
Distinct callsigns
1
Country
US
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S A6C9DD.

Country allocation

The ICAO 24-bit address A6C9DD 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
N53656 - 13 2026-04-18

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-04-18 N53656 - Apr 18, 13:15 UTCApr 18, 15:35 UTC2h 20m
2026-04-18 N53656 - Apr 18, 12:15 UTCApr 18, 12:40 UTC25m
2026-04-17 N53656 - Apr 17, 16:00 UTCApr 17, 16:15 UTC15m
2026-04-17 N53656 - Apr 17, 13:50 UTCApr 17, 14:35 UTC45m
2026-04-16 N53656 - Apr 16, 15:15 UTCApr 16, 15:35 UTC20m
2026-04-16 N53656 - Apr 16, 14:35 UTCApr 16, 14:50 UTC15m
2026-04-16 N53656 - Apr 16, 13:15 UTCApr 16, 14:00 UTC45m
2026-04-16 N53656 - Apr 16, 11:54 UTCApr 16, 12:29 UTC35m
2026-04-15 N53656 - Apr 15, 19:10 UTCApr 15, 19:25 UTC15m
2026-04-15 N53656 - Apr 15, 17:05 UTCApr 15, 18:50 UTC1h 45m
2026-04-15 N53656 - Apr 15, 13:20 UTCApr 15, 14:50 UTC1h 29m
2026-04-14 N53656 LAL → LAL Apr 14, 15:10 UTCApr 14, 15:25 UTC15m
2026-04-14 N53656 - Apr 14, 14:00 UTCApr 14, 14:45 UTC45m

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 N53656 page for operator, model, and routing details .

Mode-S A6C9DD frequently asked

What is Mode-S code A6C9DD?
A6C9DD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N53656.
Where is Mode-S A6C9DD registered?
Mode-S code A6C9DD 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 A6C9DD broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A6C9DD, octal 51544735, decimal 10,930,653.
What flights does A6C9DD operate?
Mode-S A6C9DD has broadcast 1 distinct callsign, including N53656.