sensors Mode-S transponder

A6946B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N523DN · operated by DELTA AIR LINES INC

Hex
A6946B
Octal
51512153
Decimal
10,916,971
Country
US
Tail
N523DN
Type
A359
No current signal · last broadcast 16h ago
Flights observed
8
Distinct callsigns
3
Country
US
Last broadcast
16h ago

Last known position

Most recent position reported by Mode-S A6946B.

Country allocation

The ICAO 24-bit address A6946B 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 3 distinct

Callsign Airline Flights Last seen
DAL27 - 6 2026-04-13
DAL782 Delta Air Lines 1 2026-04-12
DAL158 Delta Air Lines 1 2026-04-14

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-14 DAL158 ICN → DTW Apr 14, 09:55 UTCApr 14, 11:05 UTC1h 10m
2026-04-13 DAL27 - Apr 13, 16:25 UTCApr 13, 18:35 UTC2h 10m
2026-04-13 DAL27 - Apr 13, 08:20 UTCApr 13, 11:55 UTC3h 35m
2026-04-13 DAL27 - Apr 13, 07:55 UTCApr 13, 11:50 UTC3h 55m
2026-04-13 DAL27 - Apr 13, 04:20 UTCApr 13, 08:15 UTC3h 55m
2026-04-13 DAL27 - Apr 13, 03:55 UTCApr 13, 07:40 UTC3h 45m
2026-04-13 DAL27 - Apr 13, 03:42 UTCApr 13, 18:38 UTC14h 56m
2026-04-12 DAL782 SLC → BOS Apr 12, 17:15 UTCApr 12, 20:15 UTC3h 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 N523DN page for operator, model, and routing details .

Mode-S A6946B frequently asked

What is Mode-S code A6946B?
A6946B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N523DN.
Where is Mode-S A6946B registered?
Mode-S code A6946B 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 A6946B broadcasting right now?
No active broadcast right now. Last signal was 16h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A6946B, octal 51512153, decimal 10,916,971.
What flights does A6946B operate?
Mode-S A6946B has broadcast 3 distinct callsigns, including DAL27, DAL782, DAL158.