sensors Mode-S transponder

A23BFB

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N243JQ · EMBRAER ERJ-170-200 (long wing) · operated by DELTA AIR LINES INC

Hex
A23BFB
Octal
50435773
Decimal
10,632,187
Country
US
Tail
N243JQ
Type
E75L
Broadcasting now · callsign RPA5602 · 29,425 ft
Flights observed
12
Distinct callsigns
6
Country
US
Last broadcast
1d ago

Current position

A23BFB is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A23BFB 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 6 distinct

Callsign Airline Flights Last seen
RPA5656 Republic Airlines 4 2026-04-13
RPA5646 - 3 2026-04-13
RPA5733 - 2 2026-04-13
RPA5861 - 1 2026-04-12
RPA5851 - 1 2026-04-13
RPA5842 - 1 2026-04-13

Recent flights last 12

DateFlightRouteTakeoffLandingDuration
2026-04-13 RPA5851 - Apr 13, 21:29 UTCApr 13, 23:12 UTC1h 43m
2026-04-13 RPA5646 - Apr 13, 19:50 UTCApr 13, 20:05 UTC15m
2026-04-13 RPA5646 LGA → IND Apr 13, 18:28 UTCApr 13, 20:14 UTC1h 46m
2026-04-13 RPA5646 LGA → IND Apr 13, 18:19 UTCApr 13, 19:58 UTC1h 39m
2026-04-13 RPA5842 BOS → LGA Apr 13, 16:34 UTCApr 13, 17:30 UTC56m
2026-04-13 RPA5733 JFK → BOS Apr 13, 14:22 UTCApr 13, 14:54 UTC32m
2026-04-13 RPA5733 JFK → BOS Apr 13, 14:13 UTCApr 13, 14:55 UTC42m
2026-04-13 RPA5656 LGA → BOS Apr 13, 12:20 UTCApr 13, 12:30 UTC10m
2026-04-13 RPA5656 LGA → BOS Apr 13, 11:55 UTCApr 13, 12:30 UTC35m
2026-04-13 RPA5656 LGA → BOS Apr 13, 11:21 UTCApr 13, 12:42 UTC1h 21m
2026-04-13 RPA5656 LGA → BOS Apr 13, 11:21 UTCApr 13, 12:42 UTC1h 21m
2026-04-12 RPA5861 BNA → LGA Apr 12, 18:20 UTCApr 12, 20:15 UTC1h 55m

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 N243JQ page for operator, model, and routing details .

Mode-S A23BFB frequently asked

What is Mode-S code A23BFB?
A23BFB is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N243JQ.
Where is Mode-S A23BFB registered?
Mode-S code A23BFB 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 A23BFB broadcasting right now?
Yes. Mode-S A23BFB is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A23BFB, octal 50435773, decimal 10,632,187.
What flights does A23BFB operate?
Mode-S A23BFB has broadcast 6 distinct callsigns, including RPA5656, RPA5646, RPA5733, RPA5861, RPA5851.