sensors Mode-S transponder

AB84C0

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N841ND · PIPER PA-28-140/150/160/180 · operated by UND AEROSPACE FOUNDATION

Hex
AB84C0
Octal
52702300
Decimal
11,240,640
Country
US
Tail
N841ND
Type
P28A
Broadcasting now · callsign NDU841 · 6,700 ft
Flights observed
6
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Current position

AB84C0 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address AB84C0 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
NDU841 - 6 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 NDU841 - Apr 13, 20:55 UTCApr 13, 22:50 UTC1h 55m
2026-04-13 NDU841 - Apr 13, 18:05 UTCApr 13, 19:45 UTC1h 40m
2026-04-13 NDU841 CGZ → AZA Apr 13, 16:15 UTCApr 13, 16:40 UTC25m
2026-04-13 NDU841 - Apr 13, 15:50 UTCApr 13, 16:40 UTC50m
2026-04-13 NDU841 - Apr 13, 15:15 UTCApr 13, 16:15 UTC1h 0m
2026-04-13 NDU841 - Apr 13, 13:20 UTCApr 13, 14:15 UTC55m

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 N841ND page for operator, model, and routing details .

Mode-S AB84C0 frequently asked

What is Mode-S code AB84C0?
AB84C0 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N841ND.
Where is Mode-S AB84C0 registered?
Mode-S code AB84C0 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 AB84C0 broadcasting right now?
Yes. Mode-S AB84C0 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AB84C0, octal 52702300, decimal 11,240,640.
What flights does AB84C0 operate?
Mode-S AB84C0 has broadcast 1 distinct callsign, including NDU841.