sensors Mode-S transponder

AB40E7

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N824ND · PIPER PA-28-140/150/160/180 · operated by UND AEROSPACE FOUNDATION

Hex
AB40E7
Octal
52640347
Decimal
11,223,271
Country
US
Tail
N824ND
Type
P28A
No current signal · last broadcast 1d ago
Flights observed
4
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S AB40E7.

Country allocation

The ICAO 24-bit address AB40E7 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
NDU824 - 4 2026-04-13

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-13 NDU824 - Apr 13, 19:50 UTCApr 13, 20:55 UTC1h 5m
2026-04-13 NDU824 - Apr 13, 19:35 UTCApr 13, 20:10 UTC35m
2026-04-13 NDU824 - Apr 13, 16:25 UTCApr 13, 17:35 UTC1h 10m
2026-04-13 NDU824 - Apr 13, 13:40 UTCApr 13, 14:35 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 N824ND page for operator, model, and routing details .

Mode-S AB40E7 frequently asked

What is Mode-S code AB40E7?
AB40E7 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N824ND.
Where is Mode-S AB40E7 registered?
Mode-S code AB40E7 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 AB40E7 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AB40E7, octal 52640347, decimal 11,223,271.
What flights does AB40E7 operate?
Mode-S AB40E7 has broadcast 1 distinct callsign, including NDU824.