Mode-S AE139B · Transponder Hex for 04-3709

Q: What is Mode-S code AE139B?

AE139B is an ICAO 24-bit transponder address. Assigned to 04-3709 .

Last known position

Most recent position reported by Mode-S AE139B.

Callsign history 4 distinct

Callsign	Airline	Flights	Last seen
TIGER10	-	1	2026-04-16
SWOLE91	-	1	2026-04-13
DEVIL34	-	1	2026-04-14
DEVIL17	-	1	2026-04-16

Recent flights last 4

Date	Flight	Route	Takeoff	Landing	Duration
2026-04-16	TIGER10	-	Apr 16, 17:20 UTC	Apr 16, 17:44 UTC	25m
2026-04-16	DEVIL17	-	Apr 16, 13:54 UTC	Apr 16, 14:40 UTC	45m
2026-04-14	DEVIL34	-	Apr 14, 17:35 UTC	Apr 14, 18:15 UTC	40m
2026-04-13	SWOLE91	-	Apr 13, 13:50 UTC	Apr 13, 14:05 UTC	15m

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 04-3709 page for operator, model, and routing details .

Mode-S AE139B frequently asked

What is Mode-S code AE139B?

AE139B is an ICAO 24-bit transponder address. Assigned to 04-3709.

Is AE139B 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 AE139B, octal 53411633, decimal 11,408,283.

What flights does AE139B operate?

Mode-S AE139B has broadcast 4 distinct callsigns, including TIGER10, SWOLE91, DEVIL34, DEVIL17.