sensors Mode-S transponder

A813DD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N61994 · CESSNA 172 Skyhawk · operated by MOHAWK FLYING CLUB INC

Hex
A813DD
Octal
52011735
Decimal
11,015,133
Country
US
Tail
N61994
Type
C172
No current signal · last broadcast 2h ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S A813DD.

Country allocation

The ICAO 24-bit address A813DD 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
N61994 - 5 2026-04-24

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-24 N61994 - Apr 24, 16:00 UTCApr 24, 16:50 UTC50m
2026-04-22 N61994 - Apr 22, 23:15 UTCApr 22, 23:55 UTC40m
2026-04-22 N61994 - Apr 22, 15:40 UTCApr 22, 16:25 UTC45m
2026-04-22 N61994 - Apr 22, 13:15 UTCApr 22, 14:20 UTC1h 5m
2026-04-20 N61994 - Apr 20, 18:50 UTCApr 20, 19:25 UTC35m

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 N61994 page for operator, model, and routing details .

Mode-S A813DD frequently asked

What is Mode-S code A813DD?
A813DD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N61994.
Where is Mode-S A813DD registered?
Mode-S code A813DD 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 A813DD 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 A813DD, octal 52011735, decimal 11,015,133.
What flights does A813DD operate?
Mode-S A813DD has broadcast 1 distinct callsign, including N61994.