sensors Mode-S transponder

A1FF90

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N228JQ · EMBRAER ERJ-170-200 (long wing) · operated by DELTA AIR LINES INC

Hex
A1FF90
Octal
50377620
Decimal
10,616,720
Country
US
Tail
N228JQ
Type
E75L
No current signal · last broadcast 1d ago
Flights observed
9
Distinct callsigns
5
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A1FF90.

Country allocation

The ICAO 24-bit address A1FF90 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 5 distinct

Callsign Airline Flights Last seen
RPA5632 Republic Airlines 3 2026-04-13
RPA5791 - 2 2026-04-13
RPA5623 - 2 2026-04-13
RPA5826 Republic Airlines 1 2026-04-13
RPA5591 Republic Airlines 1 2026-04-12

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-04-13 RPA5623 - Apr 13, 20:45 UTCApr 13, 22:30 UTC1h 45m
2026-04-13 RPA5623 - Apr 13, 16:57 UTCApr 13, 18:51 UTC1h 54m
2026-04-13 RPA5826 IAD → LGA Apr 13, 14:53 UTCApr 13, 15:34 UTC41m
2026-04-13 RPA5632 JFK → PIT Apr 13, 12:20 UTCApr 13, 12:40 UTC20m
2026-04-13 RPA5632 JFK → PIT Apr 13, 11:55 UTCApr 13, 12:40 UTC45m
2026-04-13 RPA5632 JFK → PIT Apr 13, 10:34 UTCApr 13, 12:48 UTC2h 14m
2026-04-13 RPA5791 - Apr 13, 00:20 UTCApr 13, 02:05 UTC1h 45m
2026-04-13 RPA5791 - Apr 13, 00:12 UTCApr 13, 02:02 UTC1h 50m
2026-04-12 RPA5591 BNA → LGA Apr 12, 17:20 UTCApr 12, 19:05 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 N228JQ page for operator, model, and routing details .

Mode-S A1FF90 frequently asked

What is Mode-S code A1FF90?
A1FF90 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N228JQ.
Where is Mode-S A1FF90 registered?
Mode-S code A1FF90 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 A1FF90 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1FF90, octal 50377620, decimal 10,616,720.
What flights does A1FF90 operate?
Mode-S A1FF90 has broadcast 5 distinct callsigns, including RPA5632, RPA5791, RPA5623, RPA5826, RPA5591.