sensors Mode-S transponder

AE603C

ICAO 24-bit transponder address

Currently assigned to 17-20973 · SIKORSKY UH-60 Black Hawk

Hex
AE603C
Octal
53460074
Decimal
11,427,900
Tail
17-20973
Type
H60
No current signal · last broadcast 16h ago
Flights observed
11
Distinct callsigns
2
Country
-
Last broadcast
16h ago

Last known position

Most recent position reported by Mode-S AE603C.

Callsign history 2 distinct

Callsign Airline Flights Last seen
R20973 - 7 2026-06-02
EVAL29 - 4 2026-05-18

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-06-02 R20973 - Jun 2, 15:10 UTCJun 2, 16:25 UTC1h 15m
2026-05-27 R20973 - May 27, 14:40 UTCMay 27, 14:50 UTC10m
2026-05-19 R20973 - May 19, 14:55 UTCMay 19, 16:50 UTC1h 55m
2026-05-18 EVAL29 - May 18, 14:30 UTCMay 18, 16:00 UTC1h 30m
2026-05-14 R20973 - May 14, 18:40 UTCMay 14, 18:55 UTC15m
2026-05-14 R20973 - May 14, 13:25 UTCMay 14, 13:40 UTC15m
2026-05-11 R20973 - May 11, 17:35 UTCMay 11, 19:25 UTC1h 50m
2026-05-04 EVAL29 - May 4, 15:45 UTCMay 4, 15:55 UTC10m
2026-05-04 EVAL29 - May 4, 14:25 UTCMay 4, 15:10 UTC45m
2026-04-28 R20973 - Apr 28, 16:05 UTCApr 28, 16:25 UTC20m
2026-04-27 EVAL29 - Apr 27, 14:45 UTCApr 27, 16:15 UTC1h 30m

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 17-20973 page for operator, model, and routing details .

Mode-S AE603C frequently asked

What is Mode-S code AE603C?
AE603C is an ICAO 24-bit transponder address. Assigned to 17-20973.
Is AE603C broadcasting right now?
No active broadcast right now. Last signal was 16h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AE603C, octal 53460074, decimal 11,427,900.
What flights does AE603C operate?
Mode-S AE603C has broadcast 2 distinct callsigns, including R20973, EVAL29.