sensors Mode-S transponder

ADE7D3

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N99519 · ROBINSON R-44 Raven · operated by ALYESKA HELICOPTERS LLC

Hex
ADE7D3
Octal
53363723
Decimal
11,397,075
Country
US
Tail
N99519
Type
R44
No current signal · last broadcast 1d ago
Flights observed
2
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S ADE7D3.

Country allocation

The ICAO 24-bit address ADE7D3 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
N99519 - 2 2026-04-13

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-13 N99519 FRN → MRI Apr 13, 23:25 UTCApr 13, 23:35 UTC10m
2026-04-13 N99519 - Apr 13, 22:40 UTCApr 13, 22:55 UTC15m

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 N99519 page for operator, model, and routing details .

Mode-S ADE7D3 frequently asked

What is Mode-S code ADE7D3?
ADE7D3 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N99519.
Where is Mode-S ADE7D3 registered?
Mode-S code ADE7D3 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 ADE7D3 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 ADE7D3, octal 53363723, decimal 11,397,075.
What flights does ADE7D3 operate?
Mode-S ADE7D3 has broadcast 1 distinct callsign, including N99519.