sensors Mode-S transponder

AE51D7

ICAO 24-bit transponder address

Currently assigned to 11-20352 · SIKORSKY UH-60 Black Hawk

Hex
AE51D7
Octal
53450727
Decimal
11,424,215
Tail
11-20352
Type
H60
No current signal · last broadcast 4d ago
Flights observed
8
Distinct callsigns
1
Country
-
Last broadcast
4d ago

Last known position

Most recent position reported by Mode-S AE51D7.

Callsign history 1 distinct

Callsign Airline Flights Last seen
CROSS35 - 8 2026-07-09

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-07-09 CROSS35 DRS → ILH Jul 9, 16:15 UTCJul 9, 17:55 UTC1h 40m
2026-07-09 CROSS35 - Jul 9, 11:00 UTCJul 9, 12:55 UTC1h 55m
2026-06-30 CROSS35 - Jun 30, 17:50 UTCJun 30, 19:05 UTC1h 15m
2026-06-30 CROSS35 - Jun 30, 13:30 UTCJun 30, 15:20 UTC1h 50m
2026-06-11 CROSS35 - Jun 11, 20:10 UTCJun 11, 20:50 UTC40m
2026-06-11 CROSS35 - Jun 11, 17:55 UTCJun 11, 18:55 UTC1h 0m
2026-06-10 CROSS35 - Jun 10, 20:05 UTCJun 10, 21:55 UTC1h 50m
2026-06-10 CROSS35 - Jun 10, 13:00 UTCJun 10, 13:15 UTC15m

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 11-20352 page for operator, model, and routing details .

Mode-S AE51D7 frequently asked

What is Mode-S code AE51D7?
AE51D7 is an ICAO 24-bit transponder address. Assigned to 11-20352.
Is AE51D7 broadcasting right now?
No active broadcast right now. Last signal was 4d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AE51D7, octal 53450727, decimal 11,424,215.
What flights does AE51D7 operate?
Mode-S AE51D7 has broadcast 1 distinct callsign, including CROSS35.