sensors Mode-S transponder

A91EA7

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N687QS · CESSNA 680 Citation Latitude · operated by NETJETS SALES INC, CONMED CORP, DGKW LLC, GWT AIR LLC, LF AVIATION LLC, LIGHTHOUSE IMPORT CO

Hex
A91EA7
Octal
52217247
Decimal
11,083,431
Country
US
Tail
N687QS
Type
C68A
Photo of N687QS
No current signal · last broadcast 2d ago
Flights observed
1
Distinct callsigns
1
Country
US
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S A91EA7.

Country allocation

The ICAO 24-bit address A91EA7 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
EJA687 NetJets 1 2026-04-12

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-04-12 EJA687 MMU → TPA Apr 12, 18:30 UTCApr 12, 20:15 UTC1h 45m

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 N687QS page for operator, model, and routing details .

Mode-S A91EA7 frequently asked

What is Mode-S code A91EA7?
A91EA7 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N687QS.
Where is Mode-S A91EA7 registered?
Mode-S code A91EA7 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 A91EA7 broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A91EA7, octal 52217247, decimal 11,083,431.
What flights does A91EA7 operate?
Mode-S A91EA7 has broadcast 1 distinct callsign, including EJA687.