sensors Mode-S transponder

AD87C3

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N971EC · AIRBUS HELICOPTERS EC-135/635 · operated by AIR METHODS LLC

Hex
AD87C3
Octal
53303703
Decimal
11,372,483
Country
US
Tail
N971EC
Type
EC35
No current signal · last broadcast 1d ago
Flights observed
6
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S AD87C3.

Country allocation

The ICAO 24-bit address AD87C3 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
3023 JS Aviation 6 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 3023 SLA → EZE Apr 13, 23:05 UTCApr 13, 23:20 UTC15m
2026-04-13 3023 SLA → EZE Apr 13, 02:30 UTCApr 13, 03:00 UTC30m
2026-04-13 3023 SLA → EZE Apr 13, 01:30 UTCApr 13, 02:25 UTC55m
2026-04-12 3023 SLA → EZE Apr 12, 19:35 UTCApr 12, 20:10 UTC35m
2026-04-12 3023 SLA → EZE Apr 12, 18:50 UTCApr 12, 19:00 UTC10m
2026-04-12 3023 SLA → EZE Apr 12, 18:10 UTCApr 12, 18:45 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 N971EC page for operator, model, and routing details .

Mode-S AD87C3 frequently asked

What is Mode-S code AD87C3?
AD87C3 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N971EC.
Where is Mode-S AD87C3 registered?
Mode-S code AD87C3 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 AD87C3 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 AD87C3, octal 53303703, decimal 11,372,483.
What flights does AD87C3 operate?
Mode-S AD87C3 has broadcast 1 distinct callsign, including 3023.