sensors Mode-S transponder

AE51BC

ICAO 24-bit transponder address

Currently assigned to 11-20388 · SIKORSKY UH-60 Black Hawk

Hex
AE51BC
Octal
53450674
Decimal
11,424,188
Tail
11-20388
Type
H60
No current signal · last broadcast 21d ago
Flights observed
6
Distinct callsigns
2
Country
-
Last broadcast
21d ago

Last known position

Most recent position reported by Mode-S AE51BC.

Callsign history 2 distinct

Callsign Airline Flights Last seen
HAZE34 - 3 2026-06-23
12345678 - 3 2026-06-18

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-06-23 HAZE34 - Jun 23, 14:39 UTCJun 23, 15:55 UTC1h 15m
2026-06-23 HAZE34 - Jun 23, 10:49 UTCJun 23, 12:20 UTC1h 30m
2026-06-23 HAZE34 - Jun 23, 08:39 UTCJun 23, 09:59 UTC1h 20m
2026-06-18 12345678 - Jun 18, 15:30 UTCJun 18, 15:50 UTC20m
2026-06-18 12345678 - Jun 18, 13:05 UTCJun 18, 13:55 UTC50m
2026-06-18 12345678 - Jun 18, 09:45 UTCJun 18, 10:20 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 11-20388 page for operator, model, and routing details .

Mode-S AE51BC frequently asked

What is Mode-S code AE51BC?
AE51BC is an ICAO 24-bit transponder address. Assigned to 11-20388.
Is AE51BC broadcasting right now?
No active broadcast right now. Last signal was 21d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AE51BC, octal 53450674, decimal 11,424,188.
What flights does AE51BC operate?
Mode-S AE51BC has broadcast 2 distinct callsigns, including HAZE34, 12345678.