sensors Mode-S transponder

A1ECFD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N223JQ · EMBRAER ERJ-170-200 (long wing) · operated by DELTA AIR LINES INC

Hex
A1ECFD
Octal
50366375
Decimal
10,611,965
Country
US
Tail
N223JQ
Type
E75L
Broadcasting now · callsign RPA5629 · 32,000 ft
Flights observed
12
Distinct callsigns
7
Country
US
Last broadcast
1d ago

Current position

A1ECFD is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A1ECFD 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 7 distinct

Callsign Airline Flights Last seen
RPA5688 Republic Airlines 3 2026-04-13
RPA5799 Republic Airlines 2 2026-04-13
RPA5676 - 2 2026-04-13
RPA5659 - 2 2026-04-13
RPA5815 Republic Airlines 1 2026-04-13
RPA5650 Republic Airlines 1 2026-04-13
RPA5641 - 1 2026-04-12

Recent flights last 12

DateFlightRouteTakeoffLandingDuration
2026-04-13 RPA5650 DCA → MSN Apr 13, 22:15 UTCApr 13, 23:30 UTC1h 15m
2026-04-13 RPA5659 - Apr 13, 19:50 UTCApr 13, 21:05 UTC1h 15m
2026-04-13 RPA5659 - Apr 13, 19:46 UTCApr 13, 21:06 UTC1h 20m
2026-04-13 RPA5815 DCA → BOS Apr 13, 17:30 UTCApr 13, 18:20 UTC50m
2026-04-13 RPA5799 LGA → BOS Apr 13, 14:45 UTCApr 13, 15:44 UTC59m
2026-04-13 RPA5799 LGA → BOS Apr 13, 14:53 UTCApr 13, 15:43 UTC50m
2026-04-13 RPA5688 SDF → LGA Apr 13, 12:20 UTCApr 13, 13:00 UTC40m
2026-04-13 RPA5688 SDF → LGA Apr 13, 11:55 UTCApr 13, 13:00 UTC1h 5m
2026-04-13 RPA5688 SDF → LGA Apr 13, 11:12 UTCApr 13, 13:00 UTC1h 48m
2026-04-13 RPA5676 - Apr 13, 00:20 UTCApr 13, 01:45 UTC1h 25m
2026-04-12 RPA5676 - Apr 12, 23:55 UTCApr 13, 01:45 UTC1h 50m
2026-04-12 RPA5641 - Apr 12, 18:20 UTCApr 12, 19:45 UTC1h 25m

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 N223JQ page for operator, model, and routing details .

Mode-S A1ECFD frequently asked

What is Mode-S code A1ECFD?
A1ECFD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N223JQ.
Where is Mode-S A1ECFD registered?
Mode-S code A1ECFD 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 A1ECFD broadcasting right now?
Yes. Mode-S A1ECFD is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1ECFD, octal 50366375, decimal 10,611,965.
What flights does A1ECFD operate?
Mode-S A1ECFD has broadcast 7 distinct callsigns, including RPA5688, RPA5799, RPA5676, RPA5659, RPA5815.