sensors Mode-S transponder

3949EA

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-GSPK · BOEING 777-200

Hex
3949EA
Octal
16244752
Decimal
3,754,474
Country
FR
Tail
F-GSPK
Type
B772
Photo of F-GSPK
Broadcasting now · callsign AFR359P · 4,600 ft
Flights observed
6
Distinct callsigns
3
Country
FR
Last broadcast
17h ago

Current position

3949EA is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 3949EA falls within the block assigned to France (FR) by ICAO Annex 10, Volume III. Every aircraft registered in France 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 3 distinct

Callsign Airline Flights Last seen
AFR009 - 3 2026-04-14
AFR010 - 2 2026-04-13
AFR1U Air France 1 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-14 AFR009 - Apr 14, 09:10 UTCApr 14, 10:10 UTC1h 0m
2026-04-14 AFR009 - Apr 14, 08:45 UTCApr 14, 09:05 UTC20m
2026-04-14 AFR009 - Apr 14, 05:15 UTCApr 14, 05:30 UTC15m
2026-04-13 AFR010 - Apr 13, 22:45 UTCApr 13, 23:40 UTC55m
2026-04-13 AFR010 - Apr 13, 16:50 UTCApr 13, 18:40 UTC1h 50m
2026-04-13 AFR1U JFK → CDG Apr 13, 02:00 UTCApr 13, 03:30 UTC1h 30m

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 F-GSPK page for operator, model, and routing details .

Mode-S 3949EA frequently asked

What is Mode-S code 3949EA?
3949EA is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-GSPK.
Where is Mode-S 3949EA registered?
Mode-S code 3949EA is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3949EA broadcasting right now?
Yes. Mode-S 3949EA is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3949EA, octal 16244752, decimal 3,754,474.
What flights does 3949EA operate?
Mode-S 3949EA has broadcast 3 distinct callsigns, including AFR009, AFR010, AFR1U.