sensors Mode-S transponder

A4A0CD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N398DA · BOEING 737-800 · operated by DELTA AIR LINES INC

Hex
A4A0CD
Octal
51120315
Decimal
10,789,069
Country
US
Tail
N398DA
Type
B738
Broadcasting now · callsign DAL2536 · 32,750 ft
Flights observed
231
Distinct callsigns
20
Country
US
Last broadcast
8h ago

Current position

A4A0CD is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A4A0CD 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

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 DAL716 BOS → ATL May 29, 23:40 UTCMay 30, 02:55 UTC3h 15m
2026-05-29 DAL716 BOS → ATL May 29, 23:40 UTCMay 30, 02:53 UTC3h 13m
2026-05-29 DAL716 BOS → ATL May 29, 18:05 UTCMay 29, 22:20 UTC4h 15m
2026-05-29 DAL398 DFW → LGA May 29, 13:25 UTCMay 29, 16:30 UTC3h 5m
2026-05-29 DAL398 DFW → LGA May 29, 13:21 UTCMay 29, 16:32 UTC3h 11m
2026-05-28 DAL457 JFK → DEN May 28, 20:20 UTCMay 29, 00:00 UTC3h 40m
2026-05-28 DAL457 JFK → DEN May 28, 20:16 UTCMay 29, 00:00 UTC3h 44m
2026-05-28 DAL2623 IND → ATL May 28, 16:15 UTCMay 28, 18:30 UTC2h 15m
2026-05-28 DAL1245 BOS → MCO May 28, 12:00 UTCMay 28, 14:50 UTC2h 50m
2026-05-28 DAL1245 BOS → MCO May 28, 11:57 UTCMay 28, 14:45 UTC2h 48m
2026-05-27 DAL2461 BOS → RSW May 27, 23:35 UTCMay 28, 02:25 UTC2h 50m
2026-05-27 DAL2461 BOS → RSW May 27, 23:35 UTCMay 28, 02:24 UTC2h 49m
2026-05-27 DAL2461 BOS → RSW May 27, 19:20 UTCMay 27, 22:15 UTC2h 55m
2026-05-27 DAL2560 ATL → BDL May 27, 15:40 UTCMay 27, 17:20 UTC1h 40m
2026-05-27 DAL2560 ATL → BDL May 27, 15:35 UTCMay 27, 17:17 UTC1h 42m
2026-05-27 DAL2917 MSP → ATL May 27, 11:40 UTCMay 27, 13:40 UTC2h 0m
2026-05-27 DAL2430 RSW → JFK May 27, 00:34 UTCMay 27, 02:44 UTC2h 10m
2026-05-26 DAL2160 GRR → ATL May 26, 20:20 UTCMay 26, 23:10 UTC2h 50m
2026-05-26 DAL1500 PVD → ATL May 26, 15:14 UTCMay 26, 17:55 UTC2h 40m
2026-05-26 DAL1094 BOS → BNA May 26, 11:39 UTCMay 26, 13:50 UTC2h 10m
2026-05-25 DAL1679 CVG → TPA May 25, 22:30 UTCMay 26, 00:04 UTC1h 35m
2026-05-25 DAL1679 CVG → TPA May 25, 19:35 UTCMay 25, 21:19 UTC1h 45m
2026-05-25 DAL1600 CVG → RSW May 25, 16:20 UTCMay 25, 18:10 UTC1h 50m
2026-05-25 DAL1600 CVG → RSW May 25, 16:16 UTCMay 25, 18:07 UTC1h 51m
2026-05-25 DAL2474 BOS → RSW May 25, 12:00 UTCMay 25, 15:10 UTC3h 10m
2026-05-25 DAL2361 ATL → GNV May 25, 01:55 UTCMay 25, 02:05 UTC10m
2026-05-24 DAL1441 LGA → PBI May 24, 20:40 UTCMay 24, 23:46 UTC3h 6m
2026-05-24 DAL521 SFO → JFK May 24, 16:15 UTCMay 24, 18:50 UTC2h 35m
2026-05-24 DAL439 JFK → LAX May 24, 11:15 UTCMay 24, 13:50 UTC2h 35m
2026-05-23 DAL846 LGA → ATL May 23, 21:20 UTCMay 24, 00:30 UTC3h 10m
2026-05-23 DAL2526 MSY → ATL May 23, 15:10 UTCMay 23, 17:25 UTC2h 15m
2026-05-22 DAL2460 FSD → MSP May 22, 22:35 UTCMay 23, 00:55 UTC2h 20m
2026-05-22 DAL873 TPA → ATL May 22, 16:35 UTCMay 22, 19:45 UTC3h 10m
2026-05-22 DAL873 TPA → ATL May 22, 11:35 UTCMay 22, 14:45 UTC3h 10m
2026-05-22 DAL2226 ATL → EWR May 22, 00:30 UTCMay 22, 02:05 UTC1h 35m
2026-05-21 DAL2226 ATL → EWR May 21, 20:25 UTCMay 21, 22:25 UTC2h 0m
2026-05-21 DAL2526 MSY → ATL May 21, 15:30 UTCMay 21, 18:25 UTC2h 55m
2026-05-21 DAL2526 MSY → ATL May 21, 15:27 UTCMay 21, 18:13 UTC2h 46m
2026-05-21 DAL2018 MSP → RDU May 21, 11:05 UTCMay 21, 13:25 UTC2h 20m
2026-05-20 DAL1166 LGA → MCO May 20, 18:55 UTCMay 20, 22:35 UTC3h 40m
2026-05-20 DAL1166 LGA → MCO May 20, 13:35 UTCMay 20, 17:05 UTC3h 30m
2026-05-19 DAL2623 IND → ATL May 19, 16:15 UTCMay 19, 18:35 UTC2h 20m
2026-05-19 DAL1245 BOS → MCO May 19, 12:00 UTCMay 19, 14:30 UTC2h 30m
2026-05-19 DAL1245 BOS → MCO May 19, 11:56 UTCMay 19, 14:32 UTC2h 36m
2026-05-19 DAL1439 JAX → BOS May 19, 00:30 UTCMay 19, 03:15 UTC2h 45m
2026-05-18 DAL1439 JAX → BOS May 18, 20:20 UTCMay 18, 23:00 UTC2h 40m
2026-05-18 DAL1545 BNA → DTW May 18, 15:40 UTCMay 18, 18:25 UTC2h 45m
2026-05-18 DAL1545 BNA → DTW May 18, 15:37 UTCMay 18, 18:17 UTC2h 40m
2026-05-18 DAL2536 MSP → PHL May 18, 11:40 UTCMay 18, 13:55 UTC2h 15m
2026-05-17 DAL716 BOS → ATL May 17, 23:40 UTCMay 18, 03:05 UTC3h 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 N398DA page for operator, model, and routing details .

Mode-S A4A0CD frequently asked

What is Mode-S code A4A0CD?
A4A0CD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N398DA.
Where is Mode-S A4A0CD registered?
Mode-S code A4A0CD 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 A4A0CD broadcasting right now?
Yes. Mode-S A4A0CD is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4A0CD, octal 51120315, decimal 10,789,069.
What flights does A4A0CD operate?
Mode-S A4A0CD has broadcast 20 distinct callsigns, including DAL687, DAL716, DAL787, DAL3054, DAL398.