Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

AE21C8

ICAO 24-bit transponder address

Currently assigned to 04-27014 · SIKORSKY UH-60 Black Hawk

Hex
AE21C8
Octal
53420710
Decimal
11,411,912
Tail
04-27014
Type
H60
No current signal · last broadcast 3d ago
Flights observed
4
Distinct callsigns
2
Country
-
Last broadcast
3d ago

Last known position

Most recent position reported by Mode-S AE21C8.

Callsign history 2 distinct

Callsign Airline Flights Last seen
SPADE33 - 3 2026-04-15
SPADE80 - 1 2026-04-14

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-15 SPADE33 - Apr 15, 19:05 UTCApr 15, 19:30 UTC25m
2026-04-15 SPADE33 - Apr 15, 18:10 UTCApr 15, 19:00 UTC50m
2026-04-15 SPADE33 - Apr 15, 15:05 UTCApr 15, 16:05 UTC1h 0m
2026-04-14 SPADE80 - Apr 14, 18:55 UTCApr 14, 19:45 UTC50m

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 04-27014 page for operator, model, and routing details .

Mode-S AE21C8 frequently asked

What is Mode-S code AE21C8?
AE21C8 is an ICAO 24-bit transponder address. Assigned to 04-27014.
Is AE21C8 broadcasting right now?
No active broadcast right now. Last signal was 3d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AE21C8, octal 53420710, decimal 11,411,912.
What flights does AE21C8 operate?
Mode-S AE21C8 has broadcast 2 distinct callsigns, including SPADE33, SPADE80.