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 1h ago
Flights observed
157
Distinct callsigns
20
Country
US
Last broadcast
1h 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 Delta Air Lines 7 2026-05-17
DAL222 Delta Air Lines 7 2026-05-17
DAL71 Delta Air Lines 6 2026-05-22
DAL162 Delta Air Lines 6 2026-05-05
DAL70 Delta Air Lines 5 2026-05-21
DAL242 Delta Air Lines 5 2026-05-24
DAL225 Delta Air Lines 5 2026-05-15
DAL221 - 5 2026-04-14
DAL163 Delta Air Lines 5 2026-04-15
DAL56 Delta Air Lines 4 2026-04-15
DAL3 Delta Air Lines 4 2026-05-08
DAL257 Delta Air Lines 4 2026-04-17
DAL143 Delta Air Lines 4 2026-05-25
DAL142 Delta Air Lines 4 2026-05-13
DAL137 Delta Air Lines 4 2026-04-16
DAL136 Delta Air Lines 4 2026-04-17
DAL9 Delta Air Lines 3 2026-05-08
DAL81 Delta Air Lines 3 2026-05-29
DAL80 Delta Air Lines 3 2026-05-29
DAL57 Delta Air Lines 3 2026-05-14

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 DAL81 CDG → SEA May 29, 14:30 UTCMay 30, 00:30 UTC10h 0m
2026-05-29 DAL80 SEA → CDG May 29, 02:20 UTCMay 29, 11:40 UTC9h 20m
2026-05-28 DAL145 AMS → SEA May 28, 13:50 UTCMay 28, 23:40 UTC9h 50m
2026-05-28 DAL164 MSP → AMS May 28, 03:00 UTCMay 28, 09:30 UTC6h 30m
2026-05-28 DAL164 MSP → AMS May 28, 02:59 UTCMay 28, 11:10 UTC8h 11m
2026-05-27 DAL165 AMS → MSP May 27, 13:20 UTCMay 27, 13:30 UTC10m
2026-05-27 DAL165 AMS → MSP May 27, 13:15 UTCMay 27, 21:28 UTC8h 13m
2026-05-27 DAL144 SEA → AMS May 27, 00:59 UTCMay 27, 09:55 UTC8h 56m
2026-05-26 DAL43 LAX → SYD May 26, 10:50 UTCMay 26, 13:29 UTC2h 40m
2026-05-26 DAL43 LAX → SYD May 26, 10:44 UTCMay 26, 21:55 UTC11h 11m
2026-05-25 DAL42 SYD → LAX May 25, 21:19 UTCMay 26, 07:55 UTC10h 35m
2026-05-25 DAL42 SYD → LAX May 25, 21:18 UTCMay 26, 07:58 UTC10h 40m
2026-05-25 DAL143 FRA → DTW May 25, 09:10 UTCMay 25, 18:45 UTC9h 35m
2026-05-24 DAL242 BOS → TLV May 24, 23:25 UTCMay 25, 05:45 UTC6h 20m
2026-05-24 DAL63 FCO → ATL May 24, 12:50 UTCMay 24, 19:55 UTC7h 5m
2026-05-24 DAL108 ATL → MAD May 24, 02:10 UTCMay 24, 09:50 UTC7h 40m
2026-05-23 DAL67 FCO → ATL May 23, 11:50 UTCMay 23, 22:05 UTC10h 16m
2026-05-22 DAL66 ATL → FCO May 22, 23:31 UTCMay 23, 08:19 UTC8h 48m
2026-05-22 DAL66 ATL → FCO May 22, 23:35 UTCMay 23, 08:30 UTC8h 54m
2026-05-22 DAL71 AMS → ATL May 22, 07:25 UTCMay 22, 16:20 UTC8h 55m
2026-05-22 DAL71 AMS → ATL May 22, 07:24 UTCMay 22, 16:13 UTC8h 49m
2026-05-21 DAL70 ATL → AMS May 21, 19:35 UTCMay 22, 03:15 UTC7h 40m
2026-05-20 DAL223 ATH → ATL May 20, 07:05 UTCMay 20, 18:45 UTC11h 40m
2026-05-19 DAL240 BOS → ATH May 19, 19:35 UTCMay 20, 04:00 UTC8h 25m
2026-05-19 DAL240 BOS → ATH May 19, 19:30 UTCMay 20, 03:57 UTC8h 27m
2026-05-19 DAL59 LHR → BOS May 19, 09:05 UTCMay 19, 15:35 UTC6h 30m
2026-05-19 DAL59 LHR → BOS May 19, 09:00 UTCMay 19, 15:33 UTC6h 33m
2026-05-18 DAL16 DTW → LHR May 18, 23:20 UTCMay 19, 01:30 UTC2h 10m
2026-05-18 DAL16 DTW → LHR May 18, 23:15 UTCMay 19, 06:41 UTC7h 26m
2026-05-18 DAL17 LHR → DTW May 18, 10:05 UTCMay 18, 17:35 UTC7h 30m
2026-05-18 DAL58 BOS → LHR May 18, 00:00 UTCMay 18, 05:56 UTC5h 56m
2026-05-18 DAL58 BOS → LHR May 18, 00:00 UTCMay 18, 05:30 UTC5h 30m
2026-05-17 DAL241 ATH → BOS May 17, 10:35 UTCMay 17, 20:21 UTC9h 46m
2026-05-17 DAL241 ATH → BOS May 17, 10:35 UTCMay 17, 14:55 UTC4h 20m
2026-05-17 DAL222 ATL → ATH May 17, 08:00 UTCMay 17, 08:05 UTC5m
2026-05-16 DAL222 ATL → ATH May 16, 21:40 UTCMay 17, 08:05 UTC10h 25m
2026-05-16 DAL222 ATL → ATH May 16, 21:37 UTCMay 17, 07:45 UTC10h 8m
2026-05-16 DAL71 AMS → ATL May 16, 07:31 UTCMay 16, 16:20 UTC8h 50m
2026-05-16 DAL71 AMS → ATL May 16, 07:29 UTCMay 16, 16:25 UTC8h 56m
2026-05-15 DAL256 BOS → AMS May 15, 20:50 UTCMay 16, 03:05 UTC6h 15m
2026-05-15 DAL225 CDG → BOS May 15, 16:20 UTCMay 15, 17:25 UTC1h 5m
2026-05-15 DAL225 CDG → BOS May 15, 10:00 UTCMay 15, 16:15 UTC6h 14m
2026-05-14 DAL220 SLC → CDG May 14, 22:05 UTCMay 15, 07:25 UTC9h 20m
2026-05-14 DAL57 AMS → SLC May 14, 09:40 UTCMay 14, 19:45 UTC10h 5m
2026-05-13 DAL142 SEA → AMS May 13, 21:25 UTCMay 14, 00:35 UTC3h 10m
2026-05-13 DAL142 SEA → AMS May 13, 21:23 UTCMay 14, 06:13 UTC8h 50m
2026-05-13 DAL143 FRA → DTW May 13, 08:40 UTCMay 13, 18:15 UTC9h 35m
2026-05-12 DAL70 ATL → AMS May 12, 19:40 UTCMay 12, 22:35 UTC2h 55m
2026-05-12 DAL70 ATL → AMS May 12, 19:39 UTCMay 13, 03:42 UTC8h 3m
2026-05-11 DAL109 MAD → ATL May 11, 08:02 UTCMay 11, 16:49 UTC8h 47m

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 1h 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, DAL222, DAL71, DAL162, DAL70.