sensors Mode-S transponder

AAB1A9

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N78875 · MOONEY M-20 · operated by JANSSEN CHRISTOPHER R

Hex
AAB1A9
Octal
52530651
Decimal
11,186,601
Country
US
Tail
N78875
Type
M20P
No current signal · last broadcast 5h ago
Flights observed
11
Distinct callsigns
1
Country
US
Last broadcast
5h ago

Last known position

Most recent position reported by Mode-S AAB1A9.

Country allocation

The ICAO 24-bit address AAB1A9 falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States receives a permanent address from this block at the time of registration; the address stays with the airframe even if the aircraft is re-registered to a different operator within the country.

Callsign history 1 distinct

Callsign Airline Flights Last seen
N78875 - 11 2026-07-18

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-07-18 N78875 - Jul 18, 16:20 UTCJul 18, 16:35 UTC15m
2026-07-05 N78875 - Jul 5, 20:25 UTCJul 5, 21:20 UTC55m
2026-07-05 N78875 AMW → MXO Jul 5, 15:55 UTCJul 5, 16:50 UTC55m
2026-06-21 N78875 - Jun 21, 17:54 UTCJun 21, 18:25 UTC30m
2026-06-19 N78875 - Jun 19, 18:20 UTCJun 19, 19:29 UTC1h 10m
2026-06-17 N78875 - Jun 17, 18:50 UTCJun 17, 20:00 UTC1h 10m
2026-06-06 N78875 - Jun 6, 18:50 UTCJun 6, 19:14 UTC25m
2026-06-06 N78875 - Jun 6, 17:05 UTCJun 6, 17:40 UTC35m
2026-06-06 N78875 - Jun 6, 15:05 UTCJun 6, 15:30 UTC25m
2026-05-15 N78875 - May 15, 20:30 UTCMay 15, 21:50 UTC1h 20m
2026-04-24 N78875 - Apr 24, 17:40 UTCApr 24, 19:30 UTC1h 50m

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 N78875 page for operator, model, and routing details .

Mode-S AAB1A9 frequently asked

What is Mode-S code AAB1A9?
AAB1A9 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N78875.
Where is Mode-S AAB1A9 registered?
Mode-S code AAB1A9 is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is AAB1A9 broadcasting right now?
No active broadcast right now. Last signal was 5h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AAB1A9, octal 52530651, decimal 11,186,601.
What flights does AAB1A9 operate?
Mode-S AAB1A9 has broadcast 1 distinct callsign, including N78875.