sensors Mode-S transponder

ACA4B2

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N91338 · PIPER PA-28-140/150/160/180 · operated by KEJAIR LLC

Hex
ACA4B2
Octal
53122262
Decimal
11,314,354
Country
US
Tail
N91338
Type
P28A
No current signal · last broadcast Jul 11, 19:50 UTC
Flights observed
39
Distinct callsigns
1
Country
US
Last broadcast
Jul 11, 19:50 UTC

Last known position

Most recent position reported by Mode-S ACA4B2.

Country allocation

The ICAO 24-bit address ACA4B2 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
N91338 - 39 2026-07-11

Recent flights last 39

DateFlightRouteTakeoffLandingDuration
2026-07-11 N91338 SJC → PAO Jul 11, 19:40 UTCJul 11, 19:50 UTC10m
2026-07-11 N91338 - Jul 11, 18:15 UTCJul 11, 18:55 UTC40m
2026-07-11 N91338 - Jul 11, 14:20 UTCJul 11, 15:10 UTC50m
2026-07-11 N91338 PAO → SJC Jul 11, 06:20 UTCJul 11, 06:45 UTC25m
2026-07-08 N91338 - Jul 8, 00:55 UTCJul 8, 02:05 UTC1h 10m
2026-07-03 N91338 PAO → PAO Jul 3, 20:15 UTCJul 3, 22:00 UTC1h 45m
2026-07-01 N91338 PAO → PAO Jul 1, 17:30 UTCJul 1, 18:55 UTC1h 25m
2026-06-30 N91338 PAO → PAO Jun 30, 18:55 UTCJun 30, 19:40 UTC45m
2026-06-20 N91338 - Jun 20, 18:54 UTCJun 20, 19:24 UTC30m
2026-06-20 N91338 PAO → PAO Jun 20, 16:44 UTCJun 20, 18:10 UTC1h 25m
2026-06-13 N91338 - Jun 13, 03:55 UTCJun 13, 06:10 UTC2h 14m
2026-06-10 N91338 PAO → PAO Jun 10, 18:35 UTCJun 10, 20:30 UTC1h 55m
2026-06-08 N91338 PAO → PAO Jun 8, 19:10 UTCJun 8, 19:40 UTC30m
2026-06-06 N91338 - Jun 6, 17:44 UTCJun 6, 19:10 UTC1h 25m
2026-06-05 N91338 - Jun 5, 18:40 UTCJun 5, 20:30 UTC1h 50m
2026-05-11 N91338 - May 11, 01:00 UTCMay 11, 01:25 UTC25m
2026-05-11 N91338 - May 11, 00:10 UTCMay 11, 00:54 UTC45m
2026-05-09 N91338 PAO → PAO May 9, 22:49 UTCMay 10, 00:09 UTC1h 20m
2026-05-07 N91338 - May 7, 23:24 UTCMay 8, 00:44 UTC1h 20m
2026-05-07 N91338 - May 7, 21:45 UTCMay 7, 22:40 UTC55m
2026-05-07 N91338 - May 7, 19:45 UTCMay 7, 20:50 UTC1h 5m
2026-04-27 N91338 PAO → PAO Apr 27, 20:10 UTCApr 27, 21:05 UTC55m
2026-04-20 N91338 SBP → PAO Apr 20, 00:00 UTCApr 20, 01:25 UTC1h 25m
2026-04-19 N91338 - Apr 19, 22:05 UTCApr 19, 22:50 UTC45m
2026-04-19 N91338 - Apr 19, 20:45 UTCApr 19, 21:10 UTC25m
2026-04-18 N91338 - Apr 18, 19:55 UTCApr 18, 20:15 UTC20m
2026-04-18 N91338 - Apr 18, 18:00 UTCApr 18, 18:45 UTC45m
2026-04-17 N91338 PAO → PAO Apr 17, 19:40 UTCApr 17, 19:45 UTC5m
2026-04-17 N91338 PAO → PAO Apr 17, 19:00 UTCApr 17, 19:15 UTC15m
2026-04-17 N91338 - Apr 17, 03:20 UTCApr 17, 03:30 UTC10m
2026-04-17 N91338 - Apr 17, 02:45 UTCApr 17, 03:15 UTC30m
2026-04-15 N91338 - Apr 15, 01:05 UTCApr 15, 02:50 UTC1h 45m
2026-04-15 N91338 - Apr 15, 00:25 UTCApr 15, 00:35 UTC10m
2026-04-14 N91338 - Apr 14, 22:55 UTCApr 14, 23:40 UTC45m
2026-04-14 N91338 - Apr 14, 21:05 UTCApr 14, 22:30 UTC1h 25m
2026-04-14 N91338 - Apr 14, 18:55 UTCApr 14, 20:00 UTC1h 5m
2026-04-14 N91338 - Apr 14, 18:00 UTCApr 14, 18:45 UTC45m
2026-04-14 N91338 - Apr 14, 17:05 UTCApr 14, 17:30 UTC25m
2026-04-14 N91338 - Apr 14, 14:50 UTCApr 14, 16:35 UTC1h 45m

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 N91338 page for operator, model, and routing details .

Mode-S ACA4B2 frequently asked

What is Mode-S code ACA4B2?
ACA4B2 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N91338.
Where is Mode-S ACA4B2 registered?
Mode-S code ACA4B2 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 ACA4B2 broadcasting right now?
No active broadcast right now. Last signal was Jul 11, 19:50 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex ACA4B2, octal 53122262, decimal 11,314,354.
What flights does ACA4B2 operate?
Mode-S ACA4B2 has broadcast 1 distinct callsign, including N91338.