sensors Mode-S transponder

A6BBEF

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N533DT · AIRBUS A-321neo · operated by DELTA AIR LINES INC

Hex
A6BBEF
Octal
51535757
Decimal
10,927,087
Country
US
Tail
N533DT
Type
A21N
No current signal · last broadcast 17h ago
Flights observed
11
Distinct callsigns
5
Country
US
Last broadcast
17h ago

Last known position

Most recent position reported by Mode-S A6BBEF.

Country allocation

The ICAO 24-bit address A6BBEF 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 5 distinct

Callsign Airline Flights Last seen
DAL506 - 4 2026-04-13
DAL473 - 3 2026-04-14
DAL740 Delta Air Lines 2 2026-04-13
DAL564 - 1 2026-04-13
DAL451 - 1 2026-04-12

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-04-14 DAL473 - Apr 14, 09:10 UTCApr 14, 10:25 UTC1h 15m
2026-04-14 DAL473 - Apr 14, 07:35 UTCApr 14, 09:05 UTC1h 30m
2026-04-14 DAL473 - Apr 14, 05:48 UTCApr 14, 10:28 UTC4h 40m
2026-04-13 DAL564 - Apr 13, 21:40 UTCApr 14, 03:41 UTC6h 1m
2026-04-13 DAL506 - Apr 13, 19:50 UTCApr 13, 20:05 UTC15m
2026-04-13 DAL506 - Apr 13, 16:20 UTCApr 13, 20:05 UTC3h 45m
2026-04-13 DAL506 - Apr 13, 15:50 UTCApr 13, 19:45 UTC3h 55m
2026-04-13 DAL506 - Apr 13, 14:40 UTCApr 13, 16:00 UTC1h 20m
2026-04-13 DAL740 PWM → ATL Apr 13, 01:20 UTCApr 13, 02:25 UTC1h 5m
2026-04-12 DAL740 PWM → ATL Apr 12, 23:55 UTCApr 13, 02:25 UTC2h 30m
2026-04-12 DAL451 - Apr 12, 17:15 UTCApr 12, 19:15 UTC2h 0m

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 N533DT page for operator, model, and routing details .

Mode-S A6BBEF frequently asked

What is Mode-S code A6BBEF?
A6BBEF is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N533DT.
Where is Mode-S A6BBEF registered?
Mode-S code A6BBEF 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 A6BBEF broadcasting right now?
No active broadcast right now. Last signal was 17h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A6BBEF, octal 51535757, decimal 10,927,087.
What flights does A6BBEF operate?
Mode-S A6BBEF has broadcast 5 distinct callsigns, including DAL506, DAL473, DAL740, DAL564, DAL451.