Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A4BBDE

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N404DX · AIRBUS A-330-900 · operated by DELTA AIR LINES INC

Hex
A4BBDE
Octal
51135736
Decimal
10,795,998
Country
US
Tail
N404DX
Type
A339
No current signal · last broadcast 5h ago
Flights observed
281
Distinct callsigns
20
Country
US
Last broadcast
5h ago

Last known position

Most recent position reported by Mode-S A4BBDE.

Country allocation

The ICAO 24-bit address A4BBDE 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 20 distinct

Callsign Airline Flights Last seen
DAL241 - 9 2026-07-10
DAL3 - 8 2026-06-20
DAL257 - 8 2026-07-13
DAL221 - 8 2026-07-11
DAL71 Delta Air Lines 7 2026-06-04
DAL56 - 7 2026-07-11
DAL222 Delta Air Lines 7 2026-05-17
DAL21 - 7 2026-06-24
DAL9 - 6 2026-06-20
DAL225 Delta Air Lines 6 2026-06-03
DAL224 - 6 2026-07-11
DAL162 Delta Air Lines 6 2026-05-05
DAL157 - 6 2026-07-03
DAL142 Delta Air Lines 6 2026-06-01
DAL81 Delta Air Lines 5 2026-06-23
DAL70 Delta Air Lines 5 2026-05-21
DAL59 - 5 2026-07-07
DAL58 - 5 2026-07-06
DAL296 - 5 2026-07-09
DAL242 Delta Air Lines 5 2026-05-24

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-13 DAL257 AMS → BOS Jul 13, 13:07 UTCJul 13, 20:02 UTC6h 55m
2026-07-13 DAL257 - Jul 13, 13:10 UTCJul 13, 20:05 UTC6h 55m
2026-07-13 DAL136 - Jul 13, 02:45 UTCJul 13, 10:15 UTC7h 30m
2026-07-12 DAL137 - Jul 12, 12:55 UTCJul 12, 20:45 UTC7h 50m
2026-07-11 DAL56 SLC → AMS Jul 11, 22:45 UTCJul 12, 07:45 UTC9h 0m
2026-07-11 DAL221 - Jul 11, 09:30 UTCJul 11, 11:05 UTC1h 35m
2026-07-11 DAL221 CDG → SLC Jul 11, 09:28 UTCJul 11, 19:33 UTC10h 5m
2026-07-11 DAL224 BOS → CDG Jul 11, 00:35 UTCJul 11, 06:53 UTC6h 18m
2026-07-11 DAL224 - Jul 11, 00:35 UTCJul 11, 06:50 UTC6h 15m
2026-07-10 DAL241 ATH → BOS Jul 10, 11:03 UTCJul 10, 21:10 UTC10h 7m
2026-07-10 DAL241 ATH → BOS Jul 10, 11:05 UTCJul 10, 21:10 UTC10h 5m
2026-07-09 DAL296 ATL → ATH Jul 9, 20:50 UTCJul 10, 07:05 UTC10h 15m
2026-07-08 DAL223 ATH → ATL Jul 8, 11:40 UTCJul 8, 22:55 UTC11h 15m
2026-07-08 DAL240 BOS → ATH Jul 8, 00:34 UTCJul 8, 09:21 UTC8h 47m
2026-07-08 DAL240 BOS → ATH Jul 8, 00:35 UTCJul 8, 07:30 UTC6h 55m
2026-07-07 DAL59 - Jul 7, 09:05 UTCJul 7, 10:25 UTC1h 20m
2026-07-07 DAL59 LHR → BOS Jul 7, 09:03 UTCJul 7, 15:33 UTC6h 30m
2026-07-07 DAL59 LHR → BOS Jul 7, 09:03 UTCJul 7, 15:49 UTC6h 46m
2026-07-06 DAL16 DTW → LHR Jul 6, 22:55 UTCJul 7, 05:55 UTC7h 0m
2026-07-06 DAL16 DTW → LHR Jul 6, 22:55 UTCJul 7, 05:39 UTC6h 44m
2026-07-06 DAL17 LHR → DTW Jul 6, 11:25 UTCJul 6, 19:05 UTC7h 40m
2026-07-06 DAL17 LHR → DTW Jul 6, 11:22 UTCJul 6, 19:02 UTC7h 40m
2026-07-06 DAL58 - Jul 6, 03:25 UTCJul 6, 09:20 UTC5h 55m
2026-07-06 DAL58 BOS → LHR Jul 6, 03:24 UTCJul 6, 09:06 UTC5h 42m
2026-07-06 DAL58 BOS → BOS Jul 6, 03:10 UTCJul 6, 03:15 UTC5m
2026-07-05 DAL257 AMS → BOS Jul 5, 14:16 UTCJul 5, 21:36 UTC7h 20m
2026-07-05 DAL257 - Jul 5, 14:20 UTCJul 5, 16:05 UTC1h 45m
2026-07-05 DAL48 - Jul 5, 04:45 UTCJul 5, 05:30 UTC45m
2026-07-05 DAL48 JFK → AMS Jul 5, 04:45 UTCJul 5, 10:55 UTC6h 10m
2026-07-04 DAL213 ATH → JFK Jul 4, 14:36 UTCJul 5, 00:46 UTC10h 10m
2026-07-04 DAL213 ATH → JFK Jul 4, 14:40 UTCJul 4, 15:30 UTC50m
2026-07-04 DAL212 JFK → ATH Jul 4, 03:10 UTCJul 4, 11:47 UTC8h 37m
2026-07-04 DAL212 JFK → ATH Jul 4, 03:10 UTCJul 4, 12:00 UTC8h 50m
2026-07-03 DAL157 ACC → JFK Jul 3, 09:27 UTCJul 3, 19:27 UTC10h 0m
2026-07-02 DAL157 JFK → JFK Jul 2, 21:10 UTCJul 3, 19:30 UTC22h 20m
2026-07-01 DAL226 - Jul 1, 23:45 UTCJul 2, 08:55 UTC9h 10m
2026-07-01 DAL226 GRU → JFK Jul 1, 23:42 UTCJul 2, 08:52 UTC9h 10m
2026-07-01 DAL227 - Jul 1, 02:10 UTCJul 1, 11:15 UTC9h 5m
2026-06-30 DAL157 - Jun 30, 11:40 UTCJun 30, 19:30 UTC7h 50m
2026-06-30 DAL157 ACC → JFK Jun 30, 09:46 UTCJun 30, 20:03 UTC10h 17m
2026-06-29 DAL157 - Jun 29, 21:34 UTCJun 30, 20:00 UTC22h 26m
2026-06-29 DAL156 JFK → ACC Jun 29, 21:22 UTCJun 30, 06:51 UTC9h 29m
2026-06-29 DAL156 - Jun 29, 21:24 UTCJun 29, 22:05 UTC40m
2026-06-29 DAL273 LIS → JFK Jun 29, 09:50 UTCJun 29, 16:55 UTC7h 5m
2026-06-29 DAL272 JFK → LIS Jun 29, 01:25 UTCJun 29, 07:31 UTC6h 6m
2026-06-29 DAL272 - Jun 29, 01:25 UTCJun 29, 02:14 UTC50m
2026-06-28 DAL157 ACC → JFK Jun 28, 11:59 UTCJun 28, 22:14 UTC10h 15m
2026-06-28 DAL156 - Jun 28, 00:04 UTCJun 28, 07:40 UTC7h 35m
2026-06-27 DAL49 AMS → JFK Jun 27, 13:20 UTCJun 27, 20:49 UTC7h 30m
2026-06-27 DAL49 AMS → JFK Jun 27, 13:19 UTCJun 27, 20:46 UTC7h 27m

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 N404DX page for operator, model, and routing details .

Mode-S A4BBDE frequently asked

What is Mode-S code A4BBDE?
A4BBDE is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N404DX.
Where is Mode-S A4BBDE registered?
Mode-S code A4BBDE 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 A4BBDE 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 A4BBDE, octal 51135736, decimal 10,795,998.
What flights does A4BBDE operate?
Mode-S A4BBDE has broadcast 20 distinct callsigns, including DAL241, DAL3, DAL257, DAL221, DAL71.