sensors Mode-S transponder

A0540A

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N120DN · AIRBUS A-321 · operated by DELTA AIR LINES INC

Hex
A0540A
Octal
50052012
Decimal
10,507,274
Country
US
Tail
N120DN
Type
A321
No current signal · last broadcast 1h ago
Flights observed
506
Distinct callsigns
20
Country
US
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S A0540A.

Country allocation

The ICAO 24-bit address A0540A 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
DAL1882 - 12 2026-06-22
DAL2591 Delta Air Lines 9 2026-04-23
DAL1580 Delta Air Lines 9 2026-04-23
DAL346 - 8 2026-07-05
DAL2589 - 8 2026-06-27
DAL1730 Delta Air Lines 8 2026-04-23
DAL2603 - 7 2026-07-11
DAL1461 - 7 2026-07-10
DAL992 - 6 2026-07-13
DAL2720 - 6 2026-06-19
DAL997 - 5 2026-06-29
DAL994 - 5 2026-07-08
DAL519 Delta Air Lines 5 2026-06-24
DAL3024 - 5 2026-07-13
DAL2397 - 5 2026-07-09
DAL2067 - 5 2026-07-13
DAL1508 Delta Air Lines 5 2026-06-04
DAL998 Delta Air Lines 4 2026-06-04
DAL990 Delta Air Lines 4 2026-05-23
DAL975 Delta Air Lines 4 2026-05-01

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-15 DAL582 - Jul 15, 14:15 UTCJul 15, 15:50 UTC1h 35m
2026-07-15 DAL1200 ROC → ATL Jul 15, 10:10 UTCJul 15, 11:55 UTC1h 45m
2026-07-15 DAL2472 ATL → ROC Jul 15, 02:00 UTCJul 15, 03:40 UTC1h 40m
2026-07-14 DAL2143 DFW → ATL Jul 14, 22:25 UTCJul 15, 00:10 UTC1h 44m
2026-07-14 DAL2143 DFW → ATL Jul 14, 22:22 UTCJul 15, 00:07 UTC1h 45m
2026-07-14 DAL921 ATL → DFW Jul 14, 18:55 UTCJul 14, 20:45 UTC1h 50m
2026-07-14 DAL921 ATL → DFW Jul 14, 18:55 UTCJul 14, 20:39 UTC1h 44m
2026-07-14 DAL839 - Jul 14, 15:25 UTCJul 14, 17:05 UTC1h 40m
2026-07-14 DAL839 ATL → DFW Jul 14, 11:55 UTCJul 14, 13:50 UTC1h 55m
2026-07-14 DAL2294 - Jul 14, 02:15 UTCJul 14, 03:45 UTC1h 30m
2026-07-14 DAL2294 DTW → ATL Jul 14, 02:12 UTCJul 14, 03:40 UTC1h 28m
2026-07-13 DAL2067 ATL → DTW Jul 13, 23:05 UTCJul 14, 00:30 UTC1h 25m
2026-07-13 DAL3024 - Jul 13, 20:35 UTCJul 13, 21:25 UTC50m
2026-07-13 DAL3024 ATL → JAX Jul 13, 17:20 UTCJul 13, 18:55 UTC1h 35m
2026-07-13 DAL992 LGA → ATL Jul 13, 13:15 UTCJul 13, 15:05 UTC1h 50m
2026-07-13 DAL2466 - Jul 13, 01:35 UTCJul 13, 04:30 UTC2h 55m
2026-07-12 DAL2460 - Jul 12, 19:25 UTCJul 12, 21:45 UTC2h 20m
2026-07-12 DAL1669 - Jul 12, 16:40 UTCJul 12, 18:01 UTC1h 20m
2026-07-12 DAL1669 DTW → LGA Jul 12, 16:37 UTCJul 12, 17:53 UTC1h 16m
2026-07-12 DAL1745 - Jul 12, 12:25 UTCJul 12, 14:45 UTC2h 20m
2026-07-12 DAL956 ATL → DEN Jul 12, 03:50 UTCJul 12, 06:35 UTC2h 45m
2026-07-11 DAL1036 MSP → ATL Jul 11, 23:35 UTCJul 12, 01:35 UTC2h 0m
2026-07-11 DAL2877 DEN → MSP Jul 11, 19:25 UTCJul 11, 20:55 UTC1h 30m
2026-07-11 DAL995 ATL → DEN Jul 11, 15:10 UTCJul 11, 17:45 UTC2h 35m
2026-07-11 DAL342 LGA → ATL Jul 11, 11:15 UTCJul 11, 13:05 UTC1h 50m
2026-07-11 DAL2603 - Jul 11, 04:45 UTCJul 11, 05:50 UTC1h 5m
2026-07-11 DAL2603 DTW → LGA Jul 11, 04:41 UTCJul 11, 05:56 UTC1h 15m
2026-07-10 DAL1294 - Jul 10, 23:50 UTCJul 11, 02:20 UTC2h 30m
2026-07-10 DAL1413 ATL → FLL Jul 10, 18:05 UTCJul 10, 19:45 UTC1h 40m
2026-07-10 DAL2777 - Jul 10, 14:30 UTCJul 10, 15:55 UTC1h 25m
2026-07-10 DAL2777 DTW → ATL Jul 10, 14:27 UTCJul 10, 15:50 UTC1h 23m
2026-07-10 DAL1461 MSP → DTW Jul 10, 11:40 UTCJul 10, 12:50 UTC1h 10m
2026-07-10 DAL2647 - Jul 10, 01:40 UTCJul 10, 04:55 UTC3h 15m
2026-07-09 DAL843 - Jul 9, 20:35 UTCJul 10, 00:30 UTC3h 55m
2026-07-09 DAL2397 EWR → ATL Jul 9, 16:40 UTCJul 9, 18:25 UTC1h 45m
2026-07-09 DAL2397 ATL → EWR Jul 9, 12:40 UTCJul 9, 14:25 UTC1h 45m
2026-07-09 DAL2375 DTW → ATL Jul 9, 09:30 UTCJul 9, 11:00 UTC1h 30m
2026-07-09 DAL2940 ATL → DTW Jul 9, 03:30 UTCJul 9, 04:50 UTC1h 20m
2026-07-08 DAL488 - Jul 8, 23:45 UTCJul 9, 02:00 UTC2h 15m
2026-07-08 DAL488 - Jul 8, 20:15 UTCJul 8, 22:25 UTC2h 10m
2026-07-08 DAL994 LGA → ATL Jul 8, 17:20 UTCJul 8, 19:05 UTC1h 45m
2026-07-08 DAL557 ATL → LGA Jul 8, 13:55 UTCJul 8, 15:35 UTC1h 40m
2026-07-07 DAL2464 BOS → ATL Jul 7, 23:10 UTCJul 8, 01:25 UTC2h 15m
2026-07-07 DAL726 ATL → BOS Jul 7, 19:15 UTCJul 7, 21:25 UTC2h 10m
2026-07-07 DAL431 - Jul 7, 13:25 UTCJul 7, 15:55 UTC2h 30m
2026-07-07 DAL746 ATL → DEN Jul 7, 00:15 UTCJul 7, 03:00 UTC2h 45m
2026-07-07 DAL746 ATL → DEN Jul 7, 00:12 UTCJul 7, 02:53 UTC2h 41m
2026-07-06 DAL1408 - Jul 6, 19:55 UTCJul 6, 21:45 UTC1h 50m
2026-07-06 DAL1408 SAT → ATL Jul 6, 19:50 UTCJul 6, 21:50 UTC2h 0m
2026-07-06 DAL1408 - Jul 6, 16:35 UTCJul 6, 18:30 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 N120DN page for operator, model, and routing details .

Mode-S A0540A frequently asked

What is Mode-S code A0540A?
A0540A is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N120DN.
Where is Mode-S A0540A registered?
Mode-S code A0540A 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 A0540A 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 A0540A, octal 50052012, decimal 10,507,274.
What flights does A0540A operate?
Mode-S A0540A has broadcast 20 distinct callsigns, including DAL1882, DAL2591, DAL1580, DAL346, DAL2589.