Mode-S AE51B4 · Transponder Hex for 11-20369

Q: What is Mode-S code AE51B4?

AE51B4 is an ICAO 24-bit transponder address. Assigned to 11-20369 .

Last known position

Most recent position reported by Mode-S AE51B4.

Callsign history 2 distinct

Callsign	Airline	Flights	Last seen
PAT01	-	2	2026-04-13
PAT30	-	1	2026-04-13

Recent flights last 3

Date	Flight	Route	Takeoff	Landing	Duration
2026-04-13	PAT30	-	Apr 13, 22:10 UTC	Apr 13, 23:25 UTC	1h 15m
2026-04-13	PAT01	-	Apr 13, 19:50 UTC	Apr 13, 20:55 UTC	1h 5m
2026-04-13	PAT01	-	Apr 13, 19:25 UTC	Apr 13, 19:45 UTC	20m

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 11-20369 page for operator, model, and routing details .

Mode-S AE51B4 frequently asked

What is Mode-S code AE51B4?

AE51B4 is an ICAO 24-bit transponder address. Assigned to 11-20369.

Is AE51B4 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 AE51B4, octal 53450664, decimal 11,424,180.

What flights does AE51B4 operate?

Mode-S AE51B4 has broadcast 2 distinct callsigns, including PAT01, PAT30.